1999 SR5 4x4 5VZ-FE idling low when warmed up
#21
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Thread Starter
I'm on a tight budget, so I'm going to have to wait on the wires until a later time. I looked them over, though, and they look pretty good.
I tilted the intake silencer and got it to drain out as much oil as possible, which I wiped up with paper towels and tossed. The oil was on the clean side (i.e., not burned or very dirty), so not much to see. It was seeping out of the slot in the intake silencer visible in this photo (not my pic; I couldn't get my photos to come out).
I tilted the intake silencer and got it to drain out as much oil as possible, which I wiped up with paper towels and tossed. The oil was on the clean side (i.e., not burned or very dirty), so not much to see. It was seeping out of the slot in the intake silencer visible in this photo (not my pic; I couldn't get my photos to come out).
#22
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ok tight budget... Check the resistance of the wires...
and that oil has a reminder to me that I said I have a K&N OEM replacement filter in it, I believe that just maybe the owner previous to you ran one as well but removed it before the sale and this is most likely where the oil came from!!
On that note I will definitely suggest if you haven't already clean the maf and see if that helps....
if you do not know what type of resistance you are looking for there is a section in the FSM that specifies the max resistance it is linked in the general info non vehicle related section....
and that oil has a reminder to me that I said I have a K&N OEM replacement filter in it, I believe that just maybe the owner previous to you ran one as well but removed it before the sale and this is most likely where the oil came from!!
On that note I will definitely suggest if you haven't already clean the maf and see if that helps....
if you do not know what type of resistance you are looking for there is a section in the FSM that specifies the max resistance it is linked in the general info non vehicle related section....
#23
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Thread Starter
Just wanted to say, I haven't disappeared, I just haven't had a chance to do anything with this for the last few days. I swapped out the plugs, as I mentioned above, but I ran into some issues. The truck got about 5 miles down the road and started shaking rapidly (like going over rumble strips). I braked to slow down from ~55 mph (I thought I had a flat or something), and the shaking quadrupled.
I think (hope) the issue was an improperly gapped plug. They were those 'factory gapped' dual electrode plugs (Denso K16TR11) recommended in the Haynes book. I swapped them back for the old plugs and checked the gaps on the new ones, finding one plug improperly gapped (should have checked previously). I was ordering a package from rockauto already, so rather than fool with trying to fix the defective plug, I just went ahead and ordered a new one. I'll install next week when I've got time, and then continue on the idling issue.
I've got jury duty on Monday, so no idea when I'll be free.
I think (hope) the issue was an improperly gapped plug. They were those 'factory gapped' dual electrode plugs (Denso K16TR11) recommended in the Haynes book. I swapped them back for the old plugs and checked the gaps on the new ones, finding one plug improperly gapped (should have checked previously). I was ordering a package from rockauto already, so rather than fool with trying to fix the defective plug, I just went ahead and ordered a new one. I'll install next week when I've got time, and then continue on the idling issue.
I've got jury duty on Monday, so no idea when I'll be free.
#25
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Thread Starter
Already did.
Things I've done to date:
* Changed oil and filter
* Replaced air filter (well, back in Sept., but the problem dates before and after the change - filter still looks pretty clean)
* Removed and thoroughly cleaned Throttle Body
* Cleaned MAF
* Cleaned TPS
* Cleaned IAC Valve
* Checked vacuum hoses and replaced several with cracks
* Seafoam (1 can) in gas tank
Last edited by pendrag; 03-28-2010 at 07:15 AM.
#26
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I looked to see that I just had read another post that I have been helping a guy with and that was his issue for the opposite reason but with short time I just wanted to throw that out there...
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#29
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The same thing is happening to my 98 4runner. Your truck seems like its going to cut off when maybe stopped at a stoplight or in the drive through or anything like that. I have not noticed any humming though. Could you posibly just turn the idle up a notch? Cause this was what I was planning on doing to mine!
#31
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Thread Starter
As I understand it, the 3.4L is not designed to have the idle adjusted at the throttle - it's all supposed to be electronically controlled. Now, that said, Ironmike4x4, in another thread, said he was able to manually adjust the idle RPM by adjusting the screw behind the throttle opener
So, Ironmike4x4 was able to adjust his idle manually, but his way doesn't appear to be the way Toyota intended that it be done. I'm going to try this (eventually) as a last resort, but I would much rather find out why the idle is so low and fix the underlying problem. I've cleaned the MAF, Throttle position sensor, and IAC valve, but what I haven't done is electronically tested them - I guess that's next, along with the plugs this week. After jury duty, that is.
So, Ironmike4x4 was able to adjust his idle manually, but his way doesn't appear to be the way Toyota intended that it be done. I'm going to try this (eventually) as a last resort, but I would much rather find out why the idle is so low and fix the underlying problem. I've cleaned the MAF, Throttle position sensor, and IAC valve, but what I haven't done is electronically tested them - I guess that's next, along with the plugs this week. After jury duty, that is.
Last edited by pendrag; 03-29-2010 at 02:54 AM.
#32
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in your pic of the IAC valve did you ever let the air out of the water line that goes through the IAC??? I had to do that to mine. The line that comes off of the back of it goes down to a tube, I disconnected it there for a second with the engine running.
#33
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Thread Starter
Brief break from jury duty...
Not sure why I'd need to burp the air out of the coolant line going into the IAC. The coolant system has an air space over the reservoir, so shouldn't any air in the lines make its way there in short order? Besides, I don't know that I could even access the lines coming out of the IAC while the engine was running and the intake was on - it's under a lot of parts.
Not sure why I'd need to burp the air out of the coolant line going into the IAC. The coolant system has an air space over the reservoir, so shouldn't any air in the lines make its way there in short order? Besides, I don't know that I could even access the lines coming out of the IAC while the engine was running and the intake was on - it's under a lot of parts.
#34
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Pendrag--listen-- i keep hearing alot of REPLACING and CLEANING--but no TESTING---TEST TEST TEST--guess work wont solve the problem. I have stated time and time again that at a 160k things need to be replaced and cleaned.
"I suspect these are the original factory plugs. I haven't pulled them yet. I just ordered some denso plugs. I cleaned the MAF the other day. It's a stock 1999 SR5 4x4 with 160k miles on it"
Dont worry about that--they look good
**Replace the TPS--i am not sure how you cleaned it?? but most likely it is worn ($40--or test it with an Ohm meter)
**O2' s need to be replaced if they are original--no doubt about it
**Take the injectors out and have them tested and cleaned
**hook up some diagnostic equipment and see what the other sensors are saying/doing
**change the wires
**AND last but not least--dual eletrode plugs will not solve your running issue--no doubt about that one either
OK--think about it like this--the MAF(also air temp sensor) measures the volume of air coming in--TPS tells the engine where the throttle is and what you are trying to do. Together, they calculate engine load and relay that information to everthing else. So, at idle your TPS may be telling it one thing but doing another because it is old and tired--considering all the other stuffs arent broken (That goes back to testing)
And I am not discouraged with you--just others who keep having you GUESS at issues.........
You will never really become good at cars unless you learn the basics of problem solving and how to test for those problems!!!
"I suspect these are the original factory plugs. I haven't pulled them yet. I just ordered some denso plugs. I cleaned the MAF the other day. It's a stock 1999 SR5 4x4 with 160k miles on it"
Dont worry about that--they look good
**Replace the TPS--i am not sure how you cleaned it?? but most likely it is worn ($40--or test it with an Ohm meter)
**O2' s need to be replaced if they are original--no doubt about it
**Take the injectors out and have them tested and cleaned
**hook up some diagnostic equipment and see what the other sensors are saying/doing
**change the wires
**AND last but not least--dual eletrode plugs will not solve your running issue--no doubt about that one either
OK--think about it like this--the MAF(also air temp sensor) measures the volume of air coming in--TPS tells the engine where the throttle is and what you are trying to do. Together, they calculate engine load and relay that information to everthing else. So, at idle your TPS may be telling it one thing but doing another because it is old and tired--considering all the other stuffs arent broken (That goes back to testing)
And I am not discouraged with you--just others who keep having you GUESS at issues.........
You will never really become good at cars unless you learn the basics of problem solving and how to test for those problems!!!
#36
Registered User
And--sensors can go bad without throwing a code--The get lazy or just out of spec enough to cause an issue by not throw a check engine light.
My last piece of advice--spend the money on a quality test light and multimeter--Alright all done
My last piece of advice--spend the money on a quality test light and multimeter--Alright all done
#37
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air can get trapped in the IAC and not flow through properly... It is the highest point in the coolant system so you should try to purge...
you will not be able to access the lines at the IAC but if you follow the one that goes towards the fire wall and find where it connects to the tube behind the engine it can be accessed easily, just pull the clamp there then start the truck pull the line and reconnect.
I am with hross14 on replacing the tps this can cause the issue...
The reason that we do not adjust the throttle at the screw is that as hross14 said the sensors and other things go bad and when we finally replace them then the idle is off again.
you will not be able to access the lines at the IAC but if you follow the one that goes towards the fire wall and find where it connects to the tube behind the engine it can be accessed easily, just pull the clamp there then start the truck pull the line and reconnect.
I am with hross14 on replacing the tps this can cause the issue...
The reason that we do not adjust the throttle at the screw is that as hross14 said the sensors and other things go bad and when we finally replace them then the idle is off again.
#38
Registered User
air can get trapped in the IAC and not flow through properly... It is the highest point in the coolant system so you should try to purge...
you will not be able to access the lines at the IAC but if you follow the one that goes towards the fire wall and find where it connects to the tube behind the engine it can be accessed easily, just pull the clamp there then start the truck pull the line and reconnect.
you will not be able to access the lines at the IAC but if you follow the one that goes towards the fire wall and find where it connects to the tube behind the engine it can be accessed easily, just pull the clamp there then start the truck pull the line and reconnect.
EDIT: Nevermind - brainfart. I looked at it and it makes sense to me now.
Last edited by brian2sun; 03-29-2010 at 09:40 PM.
#39
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you can adjust the idle with the throttle cable. IT IS OK TRUST ME. SAVE YOURSELF HEADACHE AND GO ADJUST YOUR IDLE AND FORGET ABOUT IT. SHOULD BE NUTS ON THREADED END OF CABLE LINE THAT CAN BE ADJUSTED FOR THIS VERY PURPOSE. THE CABLES NEED TO BE ADJUSTED EVERY 100K.
#40
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brian2sun the two coolant lines coming through the IAC are coolant lines and the one going to the fire wall is the easiest to disconnect with every thing put together and it goes towards the fire wall this is the one that I am speaking of.