Stalling when put into gear?
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From: Salt Lake, Utah
Stalling when put into gear?
Hello, I am having an issue where my car has a surging idle and when I put it into gear it usually dies, any ideas on what is happening? This is driving me crazy!
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From: Salt Lake, Utah
It’s a 1986. I currently have a brand new 383 I built. It has a TPI system on it, has an automatic transmission – the 700 R4. It was working fine when I first put the engine in, but it had a intake leak and I noticed that it was after I fix that intake leak-from the ninth injector hole-(I used a smoke machine to find it. Not sure if that’s related.) But it was shortly after I fix that it got the surging idle and I couldn’t even get out of the driveway because every time I put it in gear, it would die.
hasn’t had any codes or CEL
No air pump or egr.
hasn’t had any codes or CEL
No air pump or egr.
Last edited by moodydavid16; Nov 5, 2025 at 10:02 AM.
Drifting
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While you were tinkering with the 9th injector, did you remove and reinstall the throttle linkage? If so, maybe the adjustment changed and you need to redo the minimum air adjustment???
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not when I was doing that, but i’m curious what is the process to redo the minimum air adjustment?
Melting Slicks
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Just a question what duration Cam did you put in during the rebuild, a friend had bought an 86 Iron Head that wouldn't idle for Beans and would stumble and sometimes stall, found out the cam was too tall
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From: Salt Lake, Utah
My only gripe with that is why would it work so well before and then only now start to have issues several hours of runtime after?
Last edited by moodydavid16; Nov 5, 2025 at 06:10 PM.
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I always have just used a paperclip, any good recommendations?
If i got an adapter cable for obd1-2 would that work? I have seen them but am uncertain if it would even work?
Last edited by moodydavid16; Nov 5, 2025 at 08:33 PM.
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Melting Slicks
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I'm not sure if it can do and 86 I seem to remember a bit of a shake up our OBT scan tool became a paper weight around that time.
I'm not sure if there's a cartridge or cable according to Google they say it is but I never tried
Last edited by s carter; Nov 6, 2025 at 09:54 AM.
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From: Salt Lake, Utah
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Cool. If you had to move the adjustment screw 'a bunch' then whether it fixes your stalling or not, the min-air needed to be done as a baseline.
Because, as you see, when folks come through talking about idle, 'did you do the min-air?' is one of the first things that are asked.
Because, as you see, when folks come through talking about idle, 'did you do the min-air?' is one of the first things that are asked.
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No, I want to get all the baseline stuff figured out first before I go messing with the computer. It should work just fine without a tune. It just won’t be optimized and reach its power potential until I get it tuned but it should run just fine without it.
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Update**
I figured out the timing was off. I had my boss set it and he put it at 33 degrees total advance.
I guess he was setting as if it was a carburetor.
Anyways I was able to go back and forth between adjusting the distributor and minimum idle screw until the timing was correct and the idle was able to hold at 400 in drive. And then verified the tps was in range
It seemed to Idle great after that until I restarted it, then it started to have a surging idle again, Is this the ecm trying to relearn the IAC valve, this time its going between ~500-~1500 rpm then it seems to stabilize around 700 after a while, a lot more range than before. If so how long until this should go away?
I figured out the timing was off. I had my boss set it and he put it at 33 degrees total advance.
I guess he was setting as if it was a carburetor.Anyways I was able to go back and forth between adjusting the distributor and minimum idle screw until the timing was correct and the idle was able to hold at 400 in drive. And then verified the tps was in range
It seemed to Idle great after that until I restarted it, then it started to have a surging idle again, Is this the ecm trying to relearn the IAC valve, this time its going between ~500-~1500 rpm then it seems to stabilize around 700 after a while, a lot more range than before. If so how long until this should go away?
Drifting
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From: Liberty, SC
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From the 88 FSM... if the 86 is different... someone will let me know....
The ECM has a learning" ability which allows it to make corrections for minor variations in the fuel system to improve driveability. If the battery is disconnected to clear diagnostic codes, or for repair, the learning" process has to begin allover again. A change.may be noted in the vehicle's performance. To 'teach" the vehicle, make sure the engine is at operating temperature, and drive at part throttle, with moderate acceleration and idle conditions, until normal performance returns.
The ECM has a learning" ability which allows it to make corrections for minor variations in the fuel system to improve driveability. If the battery is disconnected to clear diagnostic codes, or for repair, the learning" process has to begin allover again. A change.may be noted in the vehicle's performance. To 'teach" the vehicle, make sure the engine is at operating temperature, and drive at part throttle, with moderate acceleration and idle conditions, until normal performance returns.
Last edited by 2011KLR; Nov 6, 2025 at 10:20 PM.