Really need some help fast - engine dies and sporadic revving
12-29-2011, 06:29 PM
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Really need some help fast - engine dies and sporadic revving
Sorry for asking so bluntly, but I was directed here by another forum for some fast possible answers...
Here's the situation and vehicle: 94 4runner, 3.0, auto/... Runs (and has since purchased) other than my current, intermittant, problem. Today was half way home from Washington to Southern Oregon, truck was running fine, then at about 60 on the freeway, it decides to immitate a problem I had about a month ago, when the engine seemed to just die...the rpm dropped to below 1000, then picked up to 1800, and dropped again (similar to a rev-limiter). Pulled the truck off the road, and it idled fine. Try to rev the engine...same thing, 1800, then rpm drops. Sound coming from the PAIR valve at same time...engine at operating temp.
I started a thread awhile ago with no answers, but am stuck in Portland with limited tools...here's the thread:
http://www.toyota-4runner.org/classi...emergency.html
I'm stuck miles from home with wife and daughter...any ideas will help
Here's the situation and vehicle: 94 4runner, 3.0, auto/... Runs (and has since purchased) other than my current, intermittant, problem. Today was half way home from Washington to Southern Oregon, truck was running fine, then at about 60 on the freeway, it decides to immitate a problem I had about a month ago, when the engine seemed to just die...the rpm dropped to below 1000, then picked up to 1800, and dropped again (similar to a rev-limiter). Pulled the truck off the road, and it idled fine. Try to rev the engine...same thing, 1800, then rpm drops. Sound coming from the PAIR valve at same time...engine at operating temp.
I started a thread awhile ago with no answers, but am stuck in Portland with limited tools...here's the thread:
http://www.toyota-4runner.org/classi...emergency.html
I'm stuck miles from home with wife and daughter...any ideas will help
12-29-2011, 08:16 PM
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I may be wrong, but I don't think it has anything to do with the air injection [PAIR system].
Just a guess, but it sounds to me more like you have a problem with the distributor [engine speed pickup] or the igniter.
Just a guess, but it sounds to me more like you have a problem with the distributor [engine speed pickup] or the igniter.
12-29-2011, 09:38 PM
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Here's THE article on PAIR system:http://autoshop101.com/forms/h65.pdf
I also doubt it's your problem at all, but by looking at the diagrams you can see how to block it off. There's a tube going straight to the AFM box. Cork it up and block the actuating vac tube coming from the VSV.
Sounds to me, really, like a bad fuel pressure regulator or throttle sensor. There's no way to bypass the regulator. You'd either have to test the fuel pressure or just throw another one on to see. Or, you could pull the vac tube from it and see if there's fuel in the line. That would mean the internal diaphragm has gone bad and won't hold pressure.
The throttle sensor, if it's a factor, you can just disconnect and see if the problem continues. The idle will jump up from doing so and seem as if it's racing, but it's perfectly safe and will run disconnected with no harm. Except to your mileage, of course.
Keep us posted!
I also doubt it's your problem at all, but by looking at the diagrams you can see how to block it off. There's a tube going straight to the AFM box. Cork it up and block the actuating vac tube coming from the VSV.
Sounds to me, really, like a bad fuel pressure regulator or throttle sensor. There's no way to bypass the regulator. You'd either have to test the fuel pressure or just throw another one on to see. Or, you could pull the vac tube from it and see if there's fuel in the line. That would mean the internal diaphragm has gone bad and won't hold pressure.
The throttle sensor, if it's a factor, you can just disconnect and see if the problem continues. The idle will jump up from doing so and seem as if it's racing, but it's perfectly safe and will run disconnected with no harm. Except to your mileage, of course.
Keep us posted!
Last edited by thook; 12-29-2011 at 09:39 PM.
12-30-2011, 06:06 AM
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Here's THE article on PAIR system:http://autoshop101.com/forms/h65.pdf
I also doubt it's your problem at all, but by looking at the diagrams you can see how to block it off. There's a tube going straight to the AFM box. Cork it up and block the actuating vac tube coming from the VSV.
Sounds to me, really, like a bad fuel pressure regulator or throttle sensor. There's no way to bypass the regulator. You'd either have to test the fuel pressure or just throw another one on to see. Or, you could pull the vac tube from it and see if there's fuel in the line. That would mean the internal diaphragm has gone bad and won't hold pressure.
The throttle sensor, if it's a factor, you can just disconnect and see if the problem continues. The idle will jump up from doing so and seem as if it's racing, but it's perfectly safe and will run disconnected with no harm. Except to your mileage, of course.
Keep us posted!
I also doubt it's your problem at all, but by looking at the diagrams you can see how to block it off. There's a tube going straight to the AFM box. Cork it up and block the actuating vac tube coming from the VSV.
Sounds to me, really, like a bad fuel pressure regulator or throttle sensor. There's no way to bypass the regulator. You'd either have to test the fuel pressure or just throw another one on to see. Or, you could pull the vac tube from it and see if there's fuel in the line. That would mean the internal diaphragm has gone bad and won't hold pressure.
The throttle sensor, if it's a factor, you can just disconnect and see if the problem continues. The idle will jump up from doing so and seem as if it's racing, but it's perfectly safe and will run disconnected with no harm. Except to your mileage, of course.
Keep us posted!
if that doesn't work...cork the tubes to the PAIR, and unhook the valves that activate it.
It just seems strange that when the engine hits 1800...be it driving in any gear, neutral, reverse, or whatever, it's like a rev-limiter and the PAIR valve activates (opens?)...it sounds like it does when the truck is first started cold.
My experience is with good old american V-8's and I am severly strugling with all the vacuum line activated sensor related tiny whatevers that make and keep these engines running...my learning curve is going straight up.
12-30-2011, 06:39 AM
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Could be something as simple as:
Have you checked your spark plug wires to see if one or more has come loose from the distributor cap? I had this happen a few times, and once they were re-secured, the rpm's increased, and no more bogging down at higher speeds. Check the clips on all wires and the coil wire as well.
Have you checked your spark plug wires to see if one or more has come loose from the distributor cap? I had this happen a few times, and once they were re-secured, the rpm's increased, and no more bogging down at higher speeds. Check the clips on all wires and the coil wire as well.
12-30-2011, 07:13 AM
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Well, if you have enough of a mechanical brain from working on the american v-8's, were you to understand/know what all that vacuum stuff does, you'd laugh at how simple it is. It "looks" complicated, but it's really not. Even the stuff that's specifically electronic in nature is not that complicated. For example, with the coolant temp sensor; as the coolant heats up, the sensor causes the voltage supply it's receiving to drop as it's being relayed back to the engine computer (ECU). This feedback tells the ECU the engine is warming and so it adjusts the amount of time/duration the injectors open to spray fuel. It leans it out. It's like a self adjusting carburetor. Another example; the fuel pressure regulator is vacuum operated. As the amount of vacuum produced by the engine changes, it changes the strength of the vacuum pull on the regulator. The stronger the pull of vacuum, the more the regulator opens up and fuel pressure in the fuel rail (where the injectors are connected) drops......like at idle. You don't need much pressure (= less fuel concentration) at idle. But, when you're accelerating, you need alot more pressure. When accelerating, the vacuum pull on the regulator drops, the regulator closes more, and the fuel pressure goes up (= greater fuel concentration). Simple mechanics, really.
The PAIR valve is supposed to open when the engine is cold or when rapid decelerating. You should be able to hear a pulsing noise from the tube connected at the AFM under those conditions. Obviously, on the freeway, the engine isn't cold, but when the engine speed drops off abruptly, the PAIR will open. That would be normal. Would you say that's what happening? Pulse secondary air is added to the exhaust stream after the process of combustion. IOW's, it's not air going into the combustion chambers. That's why it's we believe it's not the problem here.
Anyway, I take it you disconnected the throttle sensor and it didn't do the trick?
On second thinking, you said it idled fine. If the diaphragm in the regulator was bad, it wouldn't idle fine. So, that's out. What you're dealing with sounds more throttle or air flow meter related.
Is there any power loss up to the point the engine speed drops off?
The PAIR valve is supposed to open when the engine is cold or when rapid decelerating. You should be able to hear a pulsing noise from the tube connected at the AFM under those conditions. Obviously, on the freeway, the engine isn't cold, but when the engine speed drops off abruptly, the PAIR will open. That would be normal. Would you say that's what happening? Pulse secondary air is added to the exhaust stream after the process of combustion. IOW's, it's not air going into the combustion chambers. That's why it's we believe it's not the problem here.
Anyway, I take it you disconnected the throttle sensor and it didn't do the trick?
On second thinking, you said it idled fine. If the diaphragm in the regulator was bad, it wouldn't idle fine. So, that's out. What you're dealing with sounds more throttle or air flow meter related.
Is there any power loss up to the point the engine speed drops off?
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12-30-2011, 07:27 AM
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Power is fine up to 1800, idle is fine, no misses, or bobbles. The symptoms are exactly like a rev-limiter...same rpm every time, 1800 and drops to just above idle rpm with the pedal floored. Then back up to 1800, and drops back down. I can put the truck in gear (any gear) and drive it as long as the rpm's don't climb above 1800...it will shift all the way to overdrive, and shift back down. When the "limiter" hit's, the PAIR valve activates (sounds like an exhaust leak on the passenger side) and I can feell exhaust pulses coming from the reed valve cover.
I agree...vacuum operated systems are relatively simple, but, when so many are coupled together, trading information to let an ECU control function...it becomes difficult, especially when I don't have tools or diagnostic equipment to even check continuity or resistance,, nor do I have the experience with the truck to know where to look for what.
I agree...vacuum operated systems are relatively simple, but, when so many are coupled together, trading information to let an ECU control function...it becomes difficult, especially when I don't have tools or diagnostic equipment to even check continuity or resistance,, nor do I have the experience with the truck to know where to look for what.
12-30-2011, 07:58 AM
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Power is fine up to 1800, idle is fine, no misses, or bobbles. The symptoms are exactly like a rev-limiter...same rpm every time, 1800 and drops to just above idle rpm with the pedal floored. Then back up to 1800, and drops back down. I can put the truck in gear (any gear) and drive it as long as the rpm's don't climb above 1800...it will shift all the way to overdrive, and shift back down. When the "limiter" hit's, the PAIR valve activates (sounds like an exhaust leak on the passenger side) and I can feell exhaust pulses coming from the reed valve cover.
I agree...vacuum operated systems are relatively simple, but, when so many are coupled together, trading information to let an ECU control function...it becomes difficult, especially when I don't have tools or diagnostic equipment to even check continuity or resistance,, nor do I have the experience with the truck to know where to look for what.
I agree...vacuum operated systems are relatively simple, but, when so many are coupled together, trading information to let an ECU control function...it becomes difficult, especially when I don't have tools or diagnostic equipment to even check continuity or resistance,, nor do I have the experience with the truck to know where to look for what.
I wasn't trying to invalidate your situation, if you took it that way. I understand entirely.
Last edited by thook; 12-30-2011 at 08:12 AM.
12-30-2011, 08:09 AM
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No...shifts fine, load or no load...rpm is the limiting factor. Coolant is up, and reserve in the overflow. Just started it up this morning from dead cold...PAIR valve was open allowing exhaust bypass, then after it warmed up (unknown temp, just slide guage on dash), valve closed, but seems to have a slight wisper to it.
Could the valve be malfunctioning? I have been told that the PAIR has nothing to do with RPM, but according to the FSM...it does give the ECM feedback of some form? May effect rpm?
Could the valve be malfunctioning? I have been told that the PAIR has nothing to do with RPM, but according to the FSM...it does give the ECM feedback of some form? May effect rpm?
12-30-2011, 08:30 AM
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Not sure what you read and how you got that idea, but the PAIR doesn't give any direct feedback to the ECM. It can affect O2 readings which then can affect power production and the ECM's a/f adjustment, but that won't affect RPM's in the manner your seeing. IOW's, if the valve were leaking or not functioning when and like it should, you may experience an inefficiency of mileage and decrease in overall performance. The only direct connection the PAIR has to the ECM is the vacuum switching valve that operates the opening and closing of the valve, but that's for ECU control of the valve and not a feedback system.
Hard to say without hearing it myself, but the slight whisper may be the valve leaking a tad which could lead to a dirty intake, but it'll never act like a "limiter" on the system. Really, it's sounds like a throttle sensor problem. Did you try disconnecting it?
Edit: Or possibly the AFM.
Hard to say without hearing it myself, but the slight whisper may be the valve leaking a tad which could lead to a dirty intake, but it'll never act like a "limiter" on the system. Really, it's sounds like a throttle sensor problem. Did you try disconnecting it?
Edit: Or possibly the AFM.
Last edited by thook; 12-30-2011 at 08:32 AM.
12-30-2011, 02:30 PM
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this guys asked you like three times to simply disconnect the throttle pos. sensor and you wont even respond whether you have or not. THE SUSPENSE IS KILLING ME. I put 90% toward that sensor. UNPLUG IT! or tell us you already did, we're stupid, and it didn't help. we will gladly move down the line with you to figure this problem out
12-30-2011, 03:49 PM
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I'm truly sorry...yes, in all the chaos (wife, 1 year old, someone elses house, sleeping on floor, etc. etc.) I forgot to mention...
I borrowed freinds van, got wife/daughter home, now will be going back to Portland with more tools in the event that I need them, a meter, things like that...I don't (didn't) mean to sound difficult, just a lot of background diagnosis (wife, etc.), and really needed to just talk to you guys.
OK...PAIR valve is probably not the problem (so is said by many reply)
I am reading that I need to check the throttle sensor...with meter through full range of motion for resistance?
Temp sender behind and under manifold? Or make sure that the cooling system has NO air pockets...I havn't messed with cooling or cap since before summer when changed coolant, but will check again to make sure.
When I did last tune up, I sprayed Sea-Foam directly into the throttle body to clean, let sit, then used more while running to clean manifold and downstream of TB...did I screw something up there...? In my 5 hour drive home, I have went over everything I've done to it since purchase, trying to find a mistake or common denominator.
Hood scoop...put on during summer, but now there's a little moisture (it's winter) going in the scoop. Bad? Need to redirect cold / moist air? I put a small one on to direct cold air over the back of the engine to cool exhaust cross-over and trans. In summer it worked great, now I'm wondering...
This thing has run like a watch since I've owned it, and this is frusterating. If I've upset someone with an indirect or non-exsistant answer...I appologise.
Going to do as much research as possible coupled with you folks' great info, and head back with a full toolbox to try and solve this pain in the ass.
I borrowed freinds van, got wife/daughter home, now will be going back to Portland with more tools in the event that I need them, a meter, things like that...I don't (didn't) mean to sound difficult, just a lot of background diagnosis (wife, etc.), and really needed to just talk to you guys.
OK...PAIR valve is probably not the problem (so is said by many reply)
I am reading that I need to check the throttle sensor...with meter through full range of motion for resistance?
Temp sender behind and under manifold? Or make sure that the cooling system has NO air pockets...I havn't messed with cooling or cap since before summer when changed coolant, but will check again to make sure.
When I did last tune up, I sprayed Sea-Foam directly into the throttle body to clean, let sit, then used more while running to clean manifold and downstream of TB...did I screw something up there...? In my 5 hour drive home, I have went over everything I've done to it since purchase, trying to find a mistake or common denominator.
Hood scoop...put on during summer, but now there's a little moisture (it's winter) going in the scoop. Bad? Need to redirect cold / moist air? I put a small one on to direct cold air over the back of the engine to cool exhaust cross-over and trans. In summer it worked great, now I'm wondering...
This thing has run like a watch since I've owned it, and this is frusterating. If I've upset someone with an indirect or non-exsistant answer...I appologise.
Going to do as much research as possible coupled with you folks' great info, and head back with a full toolbox to try and solve this pain in the ass.
Last edited by csrobb007; 12-30-2011 at 03:52 PM.
12-30-2011, 04:23 PM
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I'm truly sorry...yes, in all the chaos.....
No need to apologize, man. I figured you were in the midst of juggling activity.
OK...PAIR valve is probably not the problem (so is said by many reply)
Not the problem....
I am reading that I need to check the throttle sensor...with meter through full range of motion for resistance?
Go ahead and check it when you have your tools, but first just disconnect it. That's easy and will tell you something right away before having to fiddle with a meter. If the acceleration/RPM problem goes away, you won't need to mess with the meter.....unless you really want to.
Temp sender behind and under manifold? Or make sure that the cooling system has NO air pockets...I havn't messed with cooling or cap since before summer when changed coolant, but will check again to make sure.
You mean "temp sensor". The "sender" is a sending unit for your dash instrument and has no bearing on how the motor runs. Blow off that "air in the coolant" crap. I don't know where you got that, but THAT is not your problem. Sorry to rant, but I really don't know how some of this stuff gets started and continues.
When I did last tune up, I sprayed Sea-Foam directly into the throttle body to clean, let sit, then used more while running to clean manifold and downstream of TB...did I screw something up there...? In my 5 hour drive home, I have went over everything I've done to it since purchase, trying to find a mistake or common denominator.
Not sure how you'd get solvent in the TPS through the TB. The TPS a sealed unit. However, cleaning the exterior of the TB with solvent can present problems if you get the solvent around the terminal area.
Hood scoop...put on during summer, but now there's a little moisture (it's winter) going in the scoop. Bad? Need to redirect cold / moist air? I put a small one on to direct cold air over the back of the engine to cool exhaust cross-over and trans. In summer it worked great, now I'm wondering...
Can't positively affirm/comment on the hood. I've never used one, though I can't really see where that would be a problem. I regularly run my vehicles through muddy roads and puddles and the spray does get all over the motor. Never a problem.
This thing has run like a watch since I've owned it, and this is frusterating. If I've upset someone with an indirect or non-exsistant answer...I appologise.
No one's upset, dude. Atleast, not me. I'm sure it is frustrating for you and all your dealing with....family, etc. It's the holidays....yaaayyyyy!
How many miles are on the vehicle? Throttle sensors do go out. The original one on my '86 died at around 200k.:
Going to do as much research as possible coupled with you folks' great info, and head back with a full toolbox to try and solve this pain in the ass.
No need to apologize, man. I figured you were in the midst of juggling activity.
OK...PAIR valve is probably not the problem (so is said by many reply)
Not the problem....
I am reading that I need to check the throttle sensor...with meter through full range of motion for resistance?
Go ahead and check it when you have your tools, but first just disconnect it. That's easy and will tell you something right away before having to fiddle with a meter. If the acceleration/RPM problem goes away, you won't need to mess with the meter.....unless you really want to.
Temp sender behind and under manifold? Or make sure that the cooling system has NO air pockets...I havn't messed with cooling or cap since before summer when changed coolant, but will check again to make sure.
You mean "temp sensor". The "sender" is a sending unit for your dash instrument and has no bearing on how the motor runs. Blow off that "air in the coolant" crap. I don't know where you got that, but THAT is not your problem. Sorry to rant, but I really don't know how some of this stuff gets started and continues.
When I did last tune up, I sprayed Sea-Foam directly into the throttle body to clean, let sit, then used more while running to clean manifold and downstream of TB...did I screw something up there...? In my 5 hour drive home, I have went over everything I've done to it since purchase, trying to find a mistake or common denominator.
Not sure how you'd get solvent in the TPS through the TB. The TPS a sealed unit. However, cleaning the exterior of the TB with solvent can present problems if you get the solvent around the terminal area.
Hood scoop...put on during summer, but now there's a little moisture (it's winter) going in the scoop. Bad? Need to redirect cold / moist air? I put a small one on to direct cold air over the back of the engine to cool exhaust cross-over and trans. In summer it worked great, now I'm wondering...
Can't positively affirm/comment on the hood. I've never used one, though I can't really see where that would be a problem. I regularly run my vehicles through muddy roads and puddles and the spray does get all over the motor. Never a problem.
This thing has run like a watch since I've owned it, and this is frusterating. If I've upset someone with an indirect or non-exsistant answer...I appologise.
No one's upset, dude. Atleast, not me. I'm sure it is frustrating for you and all your dealing with....family, etc. It's the holidays....yaaayyyyy!
How many miles are on the vehicle? Throttle sensors do go out. The original one on my '86 died at around 200k.:
Going to do as much research as possible coupled with you folks' great info, and head back with a full toolbox to try and solve this pain in the ass.
Last edited by thook; 12-30-2011 at 04:25 PM.
12-30-2011, 04:27 PM
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Oh, btw, your problem is not how a bad coolant temp sensor acts. You'd be lucky to get a good idle with a bad sensor. Actually, it'd be impossible.
12-30-2011, 05:20 PM
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Thook...thank you.
I will be as I said, headed back to Portland at the first of the week now that wife and daughter are tucked away at home versus on the side of a snow covered highway.
Throttle sensor will be my first step, and hope that will solve it, in fact I'm going to call my friend to do the unplug / re-plug thing before I come up...will keep all posted.
To all, thank you for your replies...much appreciated...will let everyone know what solved the problem mid-week.
thought I'd toss a pic of the engines I'm more used to playing with...
8-71 Blown 557 Ford...it runs ok and went in my '33
I will be as I said, headed back to Portland at the first of the week now that wife and daughter are tucked away at home versus on the side of a snow covered highway.
Throttle sensor will be my first step, and hope that will solve it, in fact I'm going to call my friend to do the unplug / re-plug thing before I come up...will keep all posted.
To all, thank you for your replies...much appreciated...will let everyone know what solved the problem mid-week.
thought I'd toss a pic of the engines I'm more used to playing with...
8-71 Blown 557 Ford...it runs ok and went in my '33
01-05-2012, 07:08 AM
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Well, after a few e-mails and PM's, heres a copy of what was said and done up to today...
"You are going to need a volt meter at the minimum.
TPS could have went dead after 1800 I will provide all the testing procedures at the end.
When is the last time you changed the fuel filter?
If the fuel filter is new, check fuel pressure from idle to when the problem occurs.
Pull your distributor cap and make sure you rotor isn't cracked, also look for obvious wear and damage.
Your pair valves are functional. It's what's telling them to turn on and off, that is another problem. I don't believe it is related either.
Ignition coil may be gone, cant keep up with the higher pulse.
You need to check the AFM and the TPS with a volt meter to rule them out."
AFM Test[/URL]
TPS Test[/URL]
Fuel Pressure Test[/URL]
ECU and CEL test/codes[/URL]
Ignition Testing[/URL][/QUOTE]
Got up to Portland finally...Started the truck from dead cold, idled for about ten minutes to warm up (PAIR valve again seems excessively loud). PAIR valve closed, and idled fine.
Jacked the throttle a couple of times and same problem occured...1800 then PAIR opened, idle dropped back to 500 ish, then climbed back to 1800. It did this no matter where the throttle was held.
This lasted about five minutes, while we were looking to see if there was anything obvious now that it was light out. I pulled open the four wires that were connected to the distributor (they were folded over pretty sharply) and found the white wire had some cracks and insulation missing. Truck still running, didn't get shocked or anything, but without wanting to get into a worse situation of not being able to reconnect, I sprayed some rubber (the rubber you spray on tool handles etc.) onto the wires to insulate them. My only thought was that a bare wire this close to the connector would jump a spark or power of some form across the connection as the rpm builds?
The truck sat idleing about another minute or two, when I slowly ran the throttlle up and it RPM'd fine, all the way to 4500...did this two or three times and no problem.
At this point, I didn't know where to even begin checking all the things you sent me (if nothing is malfunctioning, what do I check?), decided to load up for the seven hour drive home.
Made it home without incident...up hill, down hill, varied tempratures from 40F to 15F on the pass, 30mph getting out of Portland to 65 or 70 on I-5. Fuel consumption seemed normal...could this bare wire have been the culprit?
I'll get it in the shop today and look at things more closely (vacuum lines etc.) and do some of the tests...but it's running great...I don't get it, other than a cracked wire?
"You are going to need a volt meter at the minimum.
TPS could have went dead after 1800 I will provide all the testing procedures at the end.
When is the last time you changed the fuel filter?
If the fuel filter is new, check fuel pressure from idle to when the problem occurs.
Pull your distributor cap and make sure you rotor isn't cracked, also look for obvious wear and damage.
Your pair valves are functional. It's what's telling them to turn on and off, that is another problem. I don't believe it is related either.
Ignition coil may be gone, cant keep up with the higher pulse.
You need to check the AFM and the TPS with a volt meter to rule them out."
AFM Test[/URL]
TPS Test[/URL]
Fuel Pressure Test[/URL]
ECU and CEL test/codes[/URL]
Ignition Testing[/URL][/QUOTE]
Got up to Portland finally...Started the truck from dead cold, idled for about ten minutes to warm up (PAIR valve again seems excessively loud). PAIR valve closed, and idled fine.
Jacked the throttle a couple of times and same problem occured...1800 then PAIR opened, idle dropped back to 500 ish, then climbed back to 1800. It did this no matter where the throttle was held.
This lasted about five minutes, while we were looking to see if there was anything obvious now that it was light out. I pulled open the four wires that were connected to the distributor (they were folded over pretty sharply) and found the white wire had some cracks and insulation missing. Truck still running, didn't get shocked or anything, but without wanting to get into a worse situation of not being able to reconnect, I sprayed some rubber (the rubber you spray on tool handles etc.) onto the wires to insulate them. My only thought was that a bare wire this close to the connector would jump a spark or power of some form across the connection as the rpm builds?
The truck sat idleing about another minute or two, when I slowly ran the throttlle up and it RPM'd fine, all the way to 4500...did this two or three times and no problem.
At this point, I didn't know where to even begin checking all the things you sent me (if nothing is malfunctioning, what do I check?), decided to load up for the seven hour drive home.
Made it home without incident...up hill, down hill, varied tempratures from 40F to 15F on the pass, 30mph getting out of Portland to 65 or 70 on I-5. Fuel consumption seemed normal...could this bare wire have been the culprit?
I'll get it in the shop today and look at things more closely (vacuum lines etc.) and do some of the tests...but it's running great...I don't get it, other than a cracked wire?
Last edited by csrobb007; 01-05-2012 at 07:13 AM.
01-05-2012, 07:16 AM
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Excellent. Glad you found the problem. If you drove it all the way home without any issues, I would say just repair / replace the bad wires you found and engineered for the drive, and call it a lesson learned.
