Intermittent Idle Gremlins (1 Viewer)

[eastendmedic]

So I know that there are hundreds of Idle problem threads....but none fit like this....

Lately.....60 idles great...plenty of power....19-20" of vac with a steady needle (a little flicker)....all new vac lines....HAC Plugged, EGR Disabled....timing set....idle lean drop done.....running sweetly.....but..........

this only happens every now and then and then it is gone.....happened a total of 3 times in the past month and I can't figure it out...

I will go for a ride for ten minutes or 30 min...it doesn't matter.....it begins to run rough......has a sputtering sound from the exhaust.....if you hold your hand near the tailpipe you will feel it puffing and popping intermittently. I check all the vac lines.....the Vac is still at 19-20" and it is idling at around 650-700......it still accelerates no problem.....but just a crappy sounding idle that has a miss and sputter. I have recently opened up the heat riser flaper and rigged it in the open postition to avoid any manifold overheating issues...and did the water down the carb cleaning trick....but other than that....nada.

It is driving me nuts....any ideas.....I went through the emmisions manual...and couldn't find any issues as this is intermittent and I can't reproduce the sypmtoms all the time....Ideas?

 

[BuckMark]

So I know that there are hundreds of Idle problem threads....but none fit like this....

Lately.....60 idles great...plenty of power....19-20" of vac with a steady needle (a little flicker)....all new vac lines....HAC Plugged, EGR Disabled....timing set....idle lean drop done.....running sweetly.....but..........

this only happens every now and then and then it is gone.....happened a total of 3 times in the past month and I can't figure it out...

I will go for a ride for ten minutes or 30 min...it doesn't matter.....it begins to run rough......has a sputtering sound from the exhaust.....if you hold your hand near the tailpipe you will feel it puffing and popping intermittently. I check all the vac lines.....the Vac is still at 19-20" and it is idling at around 650-700......it still accelerates no problem.....but just a crappy sounding idle that has a miss and sputter. I have recently opened up the heat riser flaper and rigged it in the open postition to avoid any manifold overheating issues...and did the water down the carb cleaning trick....but other than that....nada.

It is driving me nuts....any ideas.....I went through the emmisions manual...and couldn't find any issues as this is intermittent and I can't reproduce the sypmtoms all the time....Ideas?

Hi Eastendmedic. I came across your very old post about idle gremlins, and wondered if you ever got any answers or advice. I’m experiencing the same issues. Newley rebuilt engine (very reputable Toyota specialist), new gas tank, lines, filters. Carb rebuilt by Jim C. Truck runs smooth and easy above idle, but seems to have a mechanical misfire at idle (mechanics triple checked for exhaust leaks). It mIgor be a long shot, but was hoping you found a solution? My mechanic is at a loss. Thanks in advance for anything you can remember.
Mark

 

[kirvesmies]

not likely you'll get an answer from eastendmedic, he's not been on here in 2
13 years. you dug deep for this one

 

[BuckMark]

Good point, I should’ve checked that first