@elripster did you ever get this issue resolved?
Perplexing poor idling, rich smelling, hesitating, with excellent full pedal performance problem. (1 Viewer)
- Thread starter elripster
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- Thread starter
- #22
Nope. New coil didn't do it. I have a new distributor and am going to check plug torque, etc... what I do know is that if I manually hold the AFM flapper door open it will start to find an idle speed.
Frank
Frank
Have you performed any of the AFM tests that are in the FSM?
- Thread starter
- #24
All of them. I even made a nice spreadsheet that turns cells green or red vs. in or out of range. I know it's long but if you read the beginning of the thread you'll see I have done extensive troubleshooting. I still have an engine that won't idle and actually now can't rev off of idle unless you really nurse it. It just oscillates up and down as the controller tries to work with whatever it is the controller is unhappy with but will not declare in a diagnostic.
What I did notice when I forced it to enrichen by pushing the flapper door open is that it does have a miss. I am going to make sure all of the new plugs are tight, wires seated, and have a new distributor.
The trail of breadcrumbs ran cold a while ago so I really don't have much left to do but replace parts until it works or part it out and buy another one.
I do have a known good computer I have tested, no change.
Frank
What I did notice when I forced it to enrichen by pushing the flapper door open is that it does have a miss. I am going to make sure all of the new plugs are tight, wires seated, and have a new distributor.
The trail of breadcrumbs ran cold a while ago so I really don't have much left to do but replace parts until it works or part it out and buy another one.
I do have a known good computer I have tested, no change.
Frank
- Thread starter
- #25
Major developments!!!
Today I changed distributor and alternator. The old alt had perfect voltage but it's been in there forever - says "Toyota" on it and so I changed it. I can keep the old as a spare.
I checked torque on all of the plugs and it was good.
I did notice one plug wire was so-so plugged in and after this the miss is gone so that was probably it.
I start the truck, it won't idle at all, not even flare up then stall. It just fires, stumbles and dies. I try this a bunch of times.... eff.
I get my kid to start it and play with the flapper door and can again get it to idle etc.... Ok, since I have what measure out to be 2 good MAF's I figure I will sacrifice one to science. I try playing with that screw on the side but it has no effect. I pop off the top and start giving up a few teeth at a time to reduce tension on the flapper and little by little it starts trying to idle but still wouldn't. I finally get it to where I can start it and nurse it up in RPM's but won't idle. By doing this I get it up there, around 4k or so, and let it just sit there, cough it out, "walk it off" maybe, I dunno, just return some of the torture it has caused me. And I let off the gas. And the RPM's come down. And it start so effing IDLE!!! Zero missing, just smooth idling!!! Granted it's at 1100 RPM but hey it's at least idling.
So I go to check timing and can't find the mark. It was easy to find before. It also stumbles like mad if I try to rev popping, etc... that usually means the timing is way off. I play with the timing end to end and rotating it clockwise which appears to be advancing it helps the stumbling. At full advance it hesitates but revs. I was able to drive around the block. I just about had a mancry.
Where I am at now is that I likely am off a tooth so that's easy to fix and will do that tomorrow morning. Once that's fixed or confirmed correct I will check the MAF voltages and if need be get some of those teeth back.
It's not all they way there but at least it's in a position where it's diagnosable.
Frank
Today I changed distributor and alternator. The old alt had perfect voltage but it's been in there forever - says "Toyota" on it and so I changed it. I can keep the old as a spare.
I checked torque on all of the plugs and it was good.
I did notice one plug wire was so-so plugged in and after this the miss is gone so that was probably it.
I start the truck, it won't idle at all, not even flare up then stall. It just fires, stumbles and dies. I try this a bunch of times.... eff.
I get my kid to start it and play with the flapper door and can again get it to idle etc.... Ok, since I have what measure out to be 2 good MAF's I figure I will sacrifice one to science. I try playing with that screw on the side but it has no effect. I pop off the top and start giving up a few teeth at a time to reduce tension on the flapper and little by little it starts trying to idle but still wouldn't. I finally get it to where I can start it and nurse it up in RPM's but won't idle. By doing this I get it up there, around 4k or so, and let it just sit there, cough it out, "walk it off" maybe, I dunno, just return some of the torture it has caused me. And I let off the gas. And the RPM's come down. And it start so effing IDLE!!! Zero missing, just smooth idling!!! Granted it's at 1100 RPM but hey it's at least idling.
So I go to check timing and can't find the mark. It was easy to find before. It also stumbles like mad if I try to rev popping, etc... that usually means the timing is way off. I play with the timing end to end and rotating it clockwise which appears to be advancing it helps the stumbling. At full advance it hesitates but revs. I was able to drive around the block. I just about had a mancry.
Where I am at now is that I likely am off a tooth so that's easy to fix and will do that tomorrow morning. Once that's fixed or confirmed correct I will check the MAF voltages and if need be get some of those teeth back.
It's not all they way there but at least it's in a position where it's diagnosable.
Frank
- Thread starter
- #26
Today:
- I verified the timing was far too late at max advance. I re-indexed and how at full retard I am about 12 deg advanced. Can't explain that, something is wrong somewhere.
- Idle went from 1100 to now just sitting at 2,100 RPM. It's the truck doing it to itself. If I rev it the idle falls to about 1k and then you actually feel the throttle move itself. It's like that little dashpot underneath is doing it. I did just spray for vac leaks and found one at the IAC, will address and retest.
Frank
- I verified the timing was far too late at max advance. I re-indexed and how at full retard I am about 12 deg advanced. Can't explain that, something is wrong somewhere.
- Idle went from 1100 to now just sitting at 2,100 RPM. It's the truck doing it to itself. If I rev it the idle falls to about 1k and then you actually feel the throttle move itself. It's like that little dashpot underneath is doing it. I did just spray for vac leaks and found one at the IAC, will address and retest.
Frank
- Thread starter
- #27
Sealed up the IAC and sprayed it out with carb cleaner. No change. I swapped in the unmolested MAF and it idles even higher, 2300-2600 RPM. Throttle response good. WFT this high idle.
Frank
Frank
- Thread starter
- #28
Adjusting tps does this...
- Thread starter
- #29
Let me tell the story the right way.
I got out in the driveway early, eager, excited, feeling empowered after the prior day's success. I cranked up some Iron Maiden and got to work. First I tackled the timing. I was pulling the distributor out when I noticed this...
I also noticed that when that rotor was installed it was not holding itself solidly in place. That bent tab might be self inflicted but that rotor just didn't grip the dizzy well at all. That's probably why the truck miraculously started to idle, it shifted enough to get timing just close enough to run. I reinstalled the Deno's and the rotor set solidly as it should.
Then I observed the rotor position. Most folks say it should be 10/11PM. I thought maybe it was a little too 2 minutes to midnight (see how I did that...)_ so I offset the dizzy a tooth and put it all together. Now I could get the timing mark within the "window" but it was still too far advanced with the dizzy backed off as far as I could go and now the idle was over 2K. Odd.
I pulled the TPS, cleaned, readjusted, but then it got into this oscillation.
I pulled the IAC after getting some RPM change when I sprayed it. I sealed it and reinstalled but it didn't help.
I was getting desperate so for turds and laughs I installed the old AFM. Now the idle got even higher but the throttle response got better. I took the molested AFM, called it Michael Jackson and put it on the shelf.
Now I was really desperate. After listening to a significant amount of 'maiden's discography I got the original IAC and figured I'd install it because.. I dunno... just did.
And I saw this...
That one with the orangeness is some Amazon prime quality right there. Notice how the plungers don't look the same. In fact they are not even the same. I installed the old one. Started the truck... and THIS happened...
It's fixed. It's perfect. 4 months of hell have come to an end. And THIS happened...
I got out in the driveway early, eager, excited, feeling empowered after the prior day's success. I cranked up some Iron Maiden and got to work. First I tackled the timing. I was pulling the distributor out when I noticed this...
I also noticed that when that rotor was installed it was not holding itself solidly in place. That bent tab might be self inflicted but that rotor just didn't grip the dizzy well at all. That's probably why the truck miraculously started to idle, it shifted enough to get timing just close enough to run. I reinstalled the Deno's and the rotor set solidly as it should.
Then I observed the rotor position. Most folks say it should be 10/11PM. I thought maybe it was a little too 2 minutes to midnight (see how I did that...)_ so I offset the dizzy a tooth and put it all together. Now I could get the timing mark within the "window" but it was still too far advanced with the dizzy backed off as far as I could go and now the idle was over 2K. Odd.
I pulled the TPS, cleaned, readjusted, but then it got into this oscillation.
I pulled the IAC after getting some RPM change when I sprayed it. I sealed it and reinstalled but it didn't help.
I was getting desperate so for turds and laughs I installed the old AFM. Now the idle got even higher but the throttle response got better. I took the molested AFM, called it Michael Jackson and put it on the shelf.
Now I was really desperate. After listening to a significant amount of 'maiden's discography I got the original IAC and figured I'd install it because.. I dunno... just did.
And I saw this...
That one with the orangeness is some Amazon prime quality right there. Notice how the plungers don't look the same. In fact they are not even the same. I installed the old one. Started the truck... and THIS happened...
It's fixed. It's perfect. 4 months of hell have come to an end. And THIS happened...
- Thread starter
- #31
And, I am not out of the woods yet. To night the truck started the issue that kicked this whole thing off. It started sputtering/hesitating at light loads. It's so odd. If I give it more than say 2/3 pedal it just takes off. One experiment I did is on a hill on the freeway I took it out of OD. I let off and tipped in 1/3 to 1/2 pedal, count 1, 2, 3 and between 3 and 5 a surge power and it takes off. Idle is for the most part very smooth but occasionally it would miss/stumble always between 650-700RPM. I can throw the MMAF (Molested Mas Air Flow...) back on and play with it for the sake of science tomorrow.
Frank
Frank
- Thread starter
- #32
So I played with the MMAF today. I could get it to stop hesitating to some degree but it smelled gassy which makes sense since I tweaked it rich. I then put the old MAF back on and it again ran better than it did with it before but still bad bogging of the line, loads of power under load. I swapped in my spare computer and it ran a little better but not much. With this computer I can sort of drive through the stumble more easily by stabbing the pedal and then letting off some. However, if you hit the tart spot (opposite of sweet spot) it runs like its running out of gas.
The idle today is nice but once and a while is too low. I am thinking my original idle control valve might marginal.
I am installing a new fuel pump and fuel pump relay tonight. Looking at the sock, it's pretty clean just a little debris on the bottom but doesn't look like anything that would starve it. I blew it out with a can of carb cleaner. Besides, starving for fuel usually doesn't permit high load performance but at this point .... About the only interesting thing I see is some rust staining in the bottom of the tank. That could be from the truck sitting for months and forming moisture. Also, there is this little metal ring that maybe was once part of a filler neck? Not sure, looks harmless, but is kicking it at the bottom with the rust.
I am trying like hell to make a camping trip this weekend and spare my kids the bad news if we cannot go. As long as it's drivable I'll go. Who knows, maybe some use will do it some good.
The idle today is nice but once and a while is too low. I am thinking my original idle control valve might marginal.
I am installing a new fuel pump and fuel pump relay tonight. Looking at the sock, it's pretty clean just a little debris on the bottom but doesn't look like anything that would starve it. I blew it out with a can of carb cleaner. Besides, starving for fuel usually doesn't permit high load performance but at this point .... About the only interesting thing I see is some rust staining in the bottom of the tank. That could be from the truck sitting for months and forming moisture. Also, there is this little metal ring that maybe was once part of a filler neck? Not sure, looks harmless, but is kicking it at the bottom with the rust.
I am trying like hell to make a camping trip this weekend and spare my kids the bad news if we cannot go. As long as it's drivable I'll go. Who knows, maybe some use will do it some good.
- Thread starter
- #33
A new fuel pump made no difference, as expected.
I am wondering if the block needs better grounding to the chassis.
Frank
I am wondering if the block needs better grounding to the chassis.
Frank
- Thread starter
- #34
Ok, I got a code 26 on the way into work. I left early to work from home and removed/golf-T'd the two lines going to the ERG valve and poof, no more problem. So I need to study that circuit but at least the truck runs well.
Now I have to figure out how the truck took 3 quarts of PS fluid without any external leaks. My guess is the new Napa PS pump is leaking into the case. I am throwing and Hail Marry, off to Oreilly's to get a pump installed, then pack, then get kids and go camping!
Frank
Now I have to figure out how the truck took 3 quarts of PS fluid without any external leaks. My guess is the new Napa PS pump is leaking into the case. I am throwing and Hail Marry, off to Oreilly's to get a pump installed, then pack, then get kids and go camping!
Frank
- Thread starter
- #35
And it's back. One odd thing, I would think that with the egr not opening I'd get the low temp code, but am not. Am now wondering if maybe I have plugged cats.
- Thread starter
- #36
Well, this thread might just turn out to be completely worthless for anyone trying to fix the same issue.
Friday, I find a PS pump, fix it, handle all my calls, pack up, get kids and hit the road to Anza. Up I15 it's running like poop at partial pedal. The first 10% is fine. The next 50% is awful. After that it runs, is a bit down on power, but is at least smooth. It turns out with all of the gear and gear on the roof 80MPH was enough load to get it to run smoothish so I that's what I did though on the hills it was struggling to hold 70 when I can usually just fly up them in 3rd. I floored it, I flogged it, I made it pay for my pain. Then, mysteriously, miraculously, in and around Pala, it just starts running fine. Tip in is completely smooth. The whole weekend in and around Bailey's cablin the truck ran great - with the EGR enabled. The Code 26 even self cleared.
I dropped it off of at the exhaust shop this morning to get the system back pressure tested to check that off the list of potential issues but if that comes out Ok I really, honestly, have no idea WTF is up with this truck. I guess I can just hope remains well.
Now, on that disappointment (Grand Tour....ha!), this will conclude root cause troubleshooting unless something else comes up. I am sorry if you read to the end hoping to find some wisdom only to find a recycled cliche and truck that has seemlingly fixed itself.
Frank
Friday, I find a PS pump, fix it, handle all my calls, pack up, get kids and hit the road to Anza. Up I15 it's running like poop at partial pedal. The first 10% is fine. The next 50% is awful. After that it runs, is a bit down on power, but is at least smooth. It turns out with all of the gear and gear on the roof 80MPH was enough load to get it to run smoothish so I that's what I did though on the hills it was struggling to hold 70 when I can usually just fly up them in 3rd. I floored it, I flogged it, I made it pay for my pain. Then, mysteriously, miraculously, in and around Pala, it just starts running fine. Tip in is completely smooth. The whole weekend in and around Bailey's cablin the truck ran great - with the EGR enabled. The Code 26 even self cleared.
I dropped it off of at the exhaust shop this morning to get the system back pressure tested to check that off the list of potential issues but if that comes out Ok I really, honestly, have no idea WTF is up with this truck. I guess I can just hope remains well.
Now, on that disappointment (Grand Tour....ha!), this will conclude root cause troubleshooting unless something else comes up. I am sorry if you read to the end hoping to find some wisdom only to find a recycled cliche and truck that has seemlingly fixed itself.
Frank
This has been a better saga than any show I've watched in years. Guess I just have to wait for season 2 now!
- Thread starter
- #38
Falling action, the exhaust backpressure check was Ok. It's running better than ever.
Outsane
Supporting Vendor
Weird! Glad it's finally fixed..
My rig does this but its a 3fe. I suspect my issue has to do with the really bad smog delete the PO did literally ripped everything out. Seriously annoying to really only have full throttle unless over 2k, not the best time to have poor mpg's
