22RE code 41 and 42, rough idle
05-14-2008, 08:58 PM
#42
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Aaron, do me a favor, would you? Unplug the connector at the distributor pick up coil, turn the key on, and see if the fuel pump still runs. I'm reading more stuff and want to check an idea.
05-14-2008, 09:06 PM
#43
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What do you mean? As if power is constantly being supplied to the FP switch in the VAM regardless of the flapper position in the meter? I don't see how that would be possible. I'd just have to do more reading on it.
OH! Well, I suppose if the flapper was hanging open. Still...I'm not sure. I believe other conditions would have to be present. Like a constant NE signal from the distributor.
Read, read, read.....
OH! Well, I suppose if the flapper was hanging open. Still...I'm not sure. I believe other conditions would have to be present. Like a constant NE signal from the distributor.
Read, read, read.....
05-14-2008, 09:44 PM
#44
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I'm looking at a wiring diagram right now and I'm seeing the following:
a) power supplied to the switched side of the circuit opening relay and to one of its two pull down coils via the switched side of the efi main relay
b) the opposite side of the coil is routed to one of the afm contacts
c) the other afm contact connects the first COR coil to ground thus activating the COR and turning the fuel pump on,
d) the second coil in the COR is permanently grounded on one terminal and receives voltage from the ignition switch
e) also has a resistor shunting the coil (which creates a simple R/C timer circuit) which turns on momentarily when the key is switched on
f) the idle-air valve supplied positive voltage via the same souce paths as the fuel pump (mentioned above) and the IAV ground is made separate from the fuel pump ground- this is the only possible path for voltage to enter the fuel pump circuit in the abscense of a COR or wiring problem
given the above, I'd use a voltmeter to check FP terminal in the diagnostic check connector for voltage when the key is on. If there is voltage, removing the circuit opening relay should cut the voltage to the FP terminal.
If it does, then we'd have to check the COR relay for continuity between the switched terminals. If it has continuity, there's the problem- the relay contacts have somehow jammed closed. If it doesn't have continuity it suggests that the resistor in the COR has burned up causing the second coil to remain energized while the key is on.
If that doesn't repair the problem, that points to a wiring problem- possibly the ECU & O2 sensor taking a ground path through the IAV and fuel pump.
a) power supplied to the switched side of the circuit opening relay and to one of its two pull down coils via the switched side of the efi main relay
b) the opposite side of the coil is routed to one of the afm contacts
c) the other afm contact connects the first COR coil to ground thus activating the COR and turning the fuel pump on,
d) the second coil in the COR is permanently grounded on one terminal and receives voltage from the ignition switch
e) also has a resistor shunting the coil (which creates a simple R/C timer circuit) which turns on momentarily when the key is switched on
f) the idle-air valve supplied positive voltage via the same souce paths as the fuel pump (mentioned above) and the IAV ground is made separate from the fuel pump ground- this is the only possible path for voltage to enter the fuel pump circuit in the abscense of a COR or wiring problem
given the above, I'd use a voltmeter to check FP terminal in the diagnostic check connector for voltage when the key is on. If there is voltage, removing the circuit opening relay should cut the voltage to the FP terminal.
If it does, then we'd have to check the COR relay for continuity between the switched terminals. If it has continuity, there's the problem- the relay contacts have somehow jammed closed. If it doesn't have continuity it suggests that the resistor in the COR has burned up causing the second coil to remain energized while the key is on.
If that doesn't repair the problem, that points to a wiring problem- possibly the ECU & O2 sensor taking a ground path through the IAV and fuel pump.
Last edited by abecedarian; 05-14-2008 at 09:53 PM.
05-14-2008, 10:06 PM
#45
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Well, I'd wondered about that, too....the relay. But, given the other symptoms, I didn't think it would be caused by that specifically. That is, if the ECU was going it would cause both......running problems and constant fuel pump activity.
Ahhhh.....but, I ain't attached to bein' right, here. It's the puzzle that I'm interested in! And, I guess I'm just lumping all the symptoms to one thing since it all happened at once.
So, how do you suppose a malfunctioning relay would cause a rich running condition and backfiring? It does nothing but relay voltage signals. After that, I could see a bad regulator, pulse dampener, or injectors (which he's already ruled out) causing the rich running condition......just not a relay.
BTW....do note, the air valve you're reading about is electrical. The air valve on his year model is not. It's the thermal wax type/TB integrated design. Functions soley by coolant temp fluctuations.
Ahhhh.....but, I ain't attached to bein' right, here. It's the puzzle that I'm interested in! And, I guess I'm just lumping all the symptoms to one thing since it all happened at once.
So, how do you suppose a malfunctioning relay would cause a rich running condition and backfiring? It does nothing but relay voltage signals. After that, I could see a bad regulator, pulse dampener, or injectors (which he's already ruled out) causing the rich running condition......just not a relay.
BTW....do note, the air valve you're reading about is electrical. The air valve on his year model is not. It's the thermal wax type/TB integrated design. Functions soley by coolant temp fluctuations.
05-14-2008, 10:23 PM
#46
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Wonder if his fuel pressure regulator is also plugged? Couldn't that cause too much fuel to be injected since the pressure runs lower when at idle and part throttle, but only goes full pressure at WOT?
May explain the noise... maybe the fuel return line is blocked...
May explain the noise... maybe the fuel return line is blocked...
05-15-2008, 04:10 AM
#47
Matthew/Abe,
I removed the NE pickup plug from the distributor. FP stayed on. Removed the harness from the ignitor (carries NE back to ECU). FP stayed on.
After reading all the material and FSM I could stand, I have come up with the following assumptions and plan of attack. Please let me know if I am on a reasonable course.
Assumption: Any element or circuit that calls for the FP must go through the COR. L2 and L3 must be energized and the relay armiture must close in order to send current to the FP. If the relay armiture (dead short) is fused closed, then the FP would be on permanently.
Process of elimination:
1. Pull COR and test resistance between pins 1 and 2 (relay armiture) looking for short.
2. Measure either current of voltage across L3 coil. If present then STA is calling for FP. With key in ON position (not cranking), STA should be active.
3. Measure either current or voltage across L2 coil. If present, then either ECU or VAF are calling for FP. ECU should briefly call for FP to build up pressure, but turn off (few seconds). VAF should not be calling for FP since engine is not cranking and no air is flowing through TB. If VAF circuit is disconnected and the FP shuts off, then VAF circuit may be grounded causing FP issue. If FP stays on, then ECU is remaining source.
Suggestions?
I removed the NE pickup plug from the distributor. FP stayed on. Removed the harness from the ignitor (carries NE back to ECU). FP stayed on.
After reading all the material and FSM I could stand, I have come up with the following assumptions and plan of attack. Please let me know if I am on a reasonable course.
Assumption: Any element or circuit that calls for the FP must go through the COR. L2 and L3 must be energized and the relay armiture must close in order to send current to the FP. If the relay armiture (dead short) is fused closed, then the FP would be on permanently.
Process of elimination:
1. Pull COR and test resistance between pins 1 and 2 (relay armiture) looking for short.
2. Measure either current of voltage across L3 coil. If present then STA is calling for FP. With key in ON position (not cranking), STA should be active.
3. Measure either current or voltage across L2 coil. If present, then either ECU or VAF are calling for FP. ECU should briefly call for FP to build up pressure, but turn off (few seconds). VAF should not be calling for FP since engine is not cranking and no air is flowing through TB. If VAF circuit is disconnected and the FP shuts off, then VAF circuit may be grounded causing FP issue. If FP stays on, then ECU is remaining source.
Suggestions?
05-15-2008, 06:51 AM
#48
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Sounds like a good plan, Aaron.
The noise is the result of fuel pressure variation and the pulse dampener being unable to dampen it. Not saying the dampener is bad, but maybe.....maybe there is a blockage in the return line....or the EVAP can is saturated. The FP is designed to deliver more fuel than the engine's requirements. In which case, there is a relief valve on some models. Not sure which or if it applies here.
I'm wondering if some of my problems may be related to the same issues here....since I'd rigged my COR to be on permanently. Hm...next things to check, I suppose.
The noise is the result of fuel pressure variation and the pulse dampener being unable to dampen it. Not saying the dampener is bad, but maybe.....maybe there is a blockage in the return line....or the EVAP can is saturated. The FP is designed to deliver more fuel than the engine's requirements. In which case, there is a relief valve on some models. Not sure which or if it applies here.
I'm wondering if some of my problems may be related to the same issues here....since I'd rigged my COR to be on permanently. Hm...next things to check, I suppose.
Last edited by thook; 05-15-2008 at 06:55 AM.
05-15-2008, 06:57 AM
#49
I feel a lit less aimless now and appreciate your and Abe's guidance. I don't have the fuel dampener (only regulator on 22RE, right?), but will check the return flow by taking off the hose from the regulator and dump it into a bucket away from the cab.
05-15-2008, 07:45 AM
#50
Registered User
I suppose that's a good idea.....checking the flow return. What's it gonna hurt, right?
Look on the autoshop site about EVAP and check that, too. It's not hard by any means and you'll atleast know if the canister is in good shape. I'm going to run all of this stuff on my 4rnr, too. I've never checked any of it and have no idea where it's at.
My 4rnr has been running rich for a good while and the O2 light has been coming since. I've advanced the timing recently to lean it out, but I've got a few possibilities I need to rule out.....EGR (reinstate it), fuel canister, COR, AAV, and maybe a couple of other things. I'm ordering a used COR and when that comes in I'm going to see if that clears up my problems.....or atleast improves it. Well, that and the AAV. I know that's shot 'cause I have no fast idle. But, the COR....I'm wondering if I'm getting "too much" fuel. Didn't think that would be possible because I thought the fuel pump only delivered a certain amount of fuel, but like I said above it delivers in excess of engine requirement by design. AND, since the COR supplies power to the AAV and mine is permanently ON, I'm wondering if it didn't burn out the AAV.
Ugh....EFI....so many things it "could" be....lol!
Last edited by thook; 05-15-2008 at 07:55 AM.
05-15-2008, 03:51 PM
#52
Low and behold, the culprit has been found. Pulled the VAF connector off and the FP stopped pumping. FP circuit in the VAF showed a short so I had little reservations about scraping away the silicon around the cap in order to expose the circuit.
http://i303.photobucket.com/albums/n...pickupweb2.jpg
Sure enough the contacts were closed. Noticed that the armature which is supposed to break the contacts was not applying pressure. Looks like the coil in the bottom has broken off the spindle. Doesn't look like an easy repair, but going to give it a try. Also going to look for a used VAF box.
Many thanks to you Matthew and Abe. Time for a cigar and a bourbon on the deck. If you were around, I would pour one for you and light one up. Next, the 3.0 I have sitting under the carport
http://i303.photobucket.com/albums/n...pickupweb2.jpg
Sure enough the contacts were closed. Noticed that the armature which is supposed to break the contacts was not applying pressure. Looks like the coil in the bottom has broken off the spindle. Doesn't look like an easy repair, but going to give it a try. Also going to look for a used VAF box.
Many thanks to you Matthew and Abe. Time for a cigar and a bourbon on the deck. If you were around, I would pour one for you and light one up. Next, the 3.0 I have sitting under the carport
Last edited by ahickman; 05-15-2008 at 05:25 PM.
05-15-2008, 04:02 PM
#53
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Congrats on finding something wrong! It's kind of satisfying to see something misbehaving... something you've been looking for... for WAY TOO LONG!
By the way, your pic isn't showing.
Now, by armature, I'm guessing you're talking about the little chromed 'arm' that sticks out from the center of the housing... that opens a little contact sticking out from the circuit board? If that's the one I'm thinking about, just grab two needle nose pliers and bend that little puppy so that it breaks the contact...
Hold everything!
Here's a suggestion-
Increase the tension on the AFM spring a bit by rotating that big gear at the bottom clockwise a tooth at a time until the fuel pump stops working- MAKE SURE YOU MARK THE ORIGINAL POSITION OF THE GEAR!!!!!
You'll be leaning out the fuel mixture a bit with each click, and bringing that armature closer to the switch.
(Found that here: http://www.celicas.org/mods/afm.html)
Leanin out the mix may help it run smoother...?
By the way, your pic isn't showing.
Now, by armature, I'm guessing you're talking about the little chromed 'arm' that sticks out from the center of the housing... that opens a little contact sticking out from the circuit board? If that's the one I'm thinking about, just grab two needle nose pliers and bend that little puppy so that it breaks the contact...
Hold everything!
Here's a suggestion-
Increase the tension on the AFM spring a bit by rotating that big gear at the bottom clockwise a tooth at a time until the fuel pump stops working- MAKE SURE YOU MARK THE ORIGINAL POSITION OF THE GEAR!!!!!
You'll be leaning out the fuel mixture a bit with each click, and bringing that armature closer to the switch.
(Found that here: http://www.celicas.org/mods/afm.html)
Leanin out the mix may help it run smoother...?
Last edited by abecedarian; 05-15-2008 at 04:03 PM.
05-15-2008, 04:18 PM
#55
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Vane (Volume) Air Flow, Air Flow Meter...
Yeah, it comes down to the acronyms people know.
Generally, VAF and AFM actually measure the volume of the air travelling through the meter through some mechanical means, usually a 'vane' or 'door' in the middle of the air stream that gets pushed aside (actually 'sucked' out of the way, but who cares eh?
) and based on how far that vane is opened, and the temperature of the air, the ECU can determine how much air is going into the engine.
The problem is that 'volume' does not equal density so in certain circumstances it is possible for the vane to open 'x' far but not really have that amount of air entering the engine. So car makers adopted different strategies- the "MAF" (or mass air flow) which has something to do with how much voltage it takes to keep a wire at a certain temperature as it is cooled off by the air flowing around it, and "MAP" (or Manifold Absolute Pressure) which uses ambient barometric pressure coupled with the 'vacuum' of the engine to determine how much air is getting in.
In general, MAF and MAP systems are quite a bit more accurate and not as succeptible to variations in air temperature.
MAP systems lend themselves to turbo and supercharging better than any of the other systems.
...in general...
Yeah, it comes down to the acronyms people know.
Generally, VAF and AFM actually measure the volume of the air travelling through the meter through some mechanical means, usually a 'vane' or 'door' in the middle of the air stream that gets pushed aside (actually 'sucked' out of the way, but who cares eh?
) and based on how far that vane is opened, and the temperature of the air, the ECU can determine how much air is going into the engine.The problem is that 'volume' does not equal density so in certain circumstances it is possible for the vane to open 'x' far but not really have that amount of air entering the engine. So car makers adopted different strategies- the "MAF" (or mass air flow) which has something to do with how much voltage it takes to keep a wire at a certain temperature as it is cooled off by the air flowing around it, and "MAP" (or Manifold Absolute Pressure) which uses ambient barometric pressure coupled with the 'vacuum' of the engine to determine how much air is getting in.
In general, MAF and MAP systems are quite a bit more accurate and not as succeptible to variations in air temperature.
MAP systems lend themselves to turbo and supercharging better than any of the other systems.
...in general...
Last edited by abecedarian; 05-15-2008 at 04:21 PM.
05-15-2008, 04:28 PM
#56
Abe, unfortunately it is the coil that provides the tension that broke away. The center post is now "free-flowing". I have it (VAF box) on my desk and am looking it over to see if or how I can pull it apart to try a repair.
05-15-2008, 04:28 PM
#57
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My truck has been having the same problem, in vermont we have the winter thaw, so I was thinking I was getting bad gas. I've changed the fuel filter, cap and rotor and wire set, plugs too. It seems when I put injector cleaner in the problem seems to go away. It did it again on the way home from work tonight and maybe my TPS is going too. I just thought it could be a poor fuel issue.
05-15-2008, 04:36 PM
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I'm not trying to highjack this post, but, if you pull the plug off the afm while running won't the motor die anyway? I'm new to toyota's and have a similar problem. Also , thanks for the input abe. I didn't know that it worked like that. Thanks.
05-15-2008, 04:48 PM
#59
Crews462, is your fuel pump running constantly (key in ON position, but not running)? Tthe VAF is easy enough to check using an volt/ohm meter. Remove the VAF connector and measure the resistance between the various terminal pairs. Refer to the following FSM link for the specs.
http://personal.utulsa.edu/~nathan-b...33volumeai.pdf
Aaron
http://personal.utulsa.edu/~nathan-b...33volumeai.pdf
Aaron
05-15-2008, 04:50 PM
#60
Registered User
Oh man, Aaron....that's great news!...lol, I guess. Still an expensive part if you have to replace it. Hope you can fix it. Didn't you test the VAM, though? You'd think something like that would show up. I guess not, huh.
Listen, if you wind up replacing, I know of couple of Joe's to hook you up with that might have something.
'89trknwby...
Sometimes yes and sometimes no. I don't know why, but I've experienced both scenarios. One purely by accident. I'd left the VAM uplugged, the truck started and ran, but very poorly. I was going,"WTF! I just fixed it!!! WAAAHHH!"....... Oh....duh.
The ECU does have "default" modes, but I'm not sure how extensive it is. In other words, I know it can compensate/adjust if some component is missing or not giving a signal (voltage) it needs, but I know what all it will do that for. So far, I've determined the throttle sensor, coolant temp sensor, and VAM.....the latter two by accident...lol!
Nice truck, crews462. You should post some pics for us all to oogle at in the main page sticky.
Listen, if you wind up replacing, I know of couple of Joe's to hook you up with that might have something.
'89trknwby...
Sometimes yes and sometimes no. I don't know why, but I've experienced both scenarios. One purely by accident. I'd left the VAM uplugged, the truck started and ran, but very poorly. I was going,"WTF! I just fixed it!!! WAAAHHH!"....... Oh....duh.
The ECU does have "default" modes, but I'm not sure how extensive it is. In other words, I know it can compensate/adjust if some component is missing or not giving a signal (voltage) it needs, but I know what all it will do that for. So far, I've determined the throttle sensor, coolant temp sensor, and VAM.....the latter two by accident...lol!
Nice truck, crews462. You should post some pics for us all to oogle at in the main page sticky.
