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TPI 350 Stalling

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Old 02-03-2017, 03:05 PM
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TPI 350 Stalling

Hello, I Purchased a 1986 Z28 back in the summer, and now I finally have some time to work on it. The first issue I have with it is that it will stall upon cold starts (unless I pump the gas) this also happens after putting it in gear, if I don't pump the gas it stalls. My cousin says it may be a vacuum leak, the garage next door says they think it may be a cam sensor. is there anything else that it may be?
Old 02-03-2017, 03:10 PM
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Re: TPI 350 Stalling

Originally Posted by 86Z28w350
Hello, I Purchased a 1986 Z28 back in the summer, and now I finally have some time to work on it. The first issue I have with it is that it will stall upon cold starts (unless I pump the gas) this also happens after putting it in gear, if I don't pump the gas it stalls. My cousin says it may be a vacuum leak, the garage next door says they think it may be a cam sensor. is there anything else that it may be?
Cam sensor lmfao, sounds lean injectors, fuel pressure, vacuum leak.
Is this just during startup ? If so I'd think ninth injector is faulty.
Old 02-03-2017, 03:41 PM
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Re: TPI 350 Stalling

It also happens when I put in gear, also when I leave it idling too long it will stall.
Old 02-03-2017, 04:11 PM
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Re: TPI 350 Stalling

Sounds like it could be injectors and it's running rich and loading up once warm.
Once warm you can check the resistance of the injectors. They should be around 16-15.5 .
A vacuum leak usually causes a higher idle if it's a minor leak.
Or a leak between the throttlebody and maf sensor.
Check engine light on ?
Old 02-03-2017, 06:50 PM
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Re: TPI 350 Stalling

Originally Posted by Tuned Performance
Sounds like it could be injectors and it's running rich and loading up once warm.
Once warm you can check the resistance of the injectors. They should be around 16-15.5 .
A vacuum leak usually causes a higher idle if it's a minor leak.
Or a leak between the throttlebody and maf sensor.
Check engine light on ?
The Check Engine light is on, however that's another problem... a previous owner hacked up the wiring under the dash, and it wouldn't work when I tried to scan it.
Old 02-03-2017, 07:28 PM
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Re: TPI 350 Stalling

http://www.theimportkiller.com/forum...hp?topic=420.0
Old 02-03-2017, 08:43 PM
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Re: TPI 350 Stalling

Originally Posted by Tuned Performance
Thank you very much, I'm going to have to try this as soon as I get out of work on monday.
Old 02-03-2017, 08:56 PM
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Re: TPI 350 Stalling

You might have a maf issue or a maf relay, I'd sure start with the trouble codes first.
Old 02-04-2017, 08:54 PM
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Re: TPI 350 Stalling

Tuned Performance..Kudos to you..You are all over the board with answers!..And good info!.If I had a Gold star sticker..you'd get one!
Old 02-04-2017, 10:28 PM
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Re: TPI 350 Stalling

Originally Posted by zero13
Tuned Performance..Kudos to you..You are all over the board with answers!..And good info!.If I had a Gold star sticker..you'd get one!
He's a super helpful resource that is greatly appreciated by the community at large

Old 02-05-2017, 09:43 AM
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Re: TPI 350 Stalling

Thanks all, if you can't get the light to blink due to hacked wiring I'll walk you through checking the ground and aldl ecm request wire.
Old 05-04-2017, 10:46 PM
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Re: TPI 350 Stalling

Hey guys, sorry for not having replied in a long time, but I finally was able to get more work done on the car, turns out that it was a bad IAC valve. I did that and a TV cable, there's now a dead spot in the throttle where it stalls. It could be a TPS, but I don't have the proper equipment yet, so I tried adjusting it mechanically, but it won't go away, along with some hesitation. Other than that she's a much different animal! (I also forgot to add that the previous owner(s) were a complete buffoon, and butchered almost ALL the wiring not in the engine bay.)

Last edited by 86Z28w350; 05-04-2017 at 10:51 PM.
Old 06-16-2017, 01:06 AM
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Re: TPI 350 Stalling

I'm having a new problem, after a few weeks of it running smoothly, I've started having a similar problem, this time it's the other way around, it idles fine for a minute, however when I give it even slight throttle it dies, the car's been abused and neglected so we think it may be bad fuel (because I don't drive it very much) or could it be something else, I'm able to put it in Neutral or park and start it back up just fine, just when there's load on the engine it seems to not like it.

Last edited by 86Z28w350; 06-16-2017 at 01:07 AM. Reason: forgot some info
Old 06-16-2017, 01:14 AM
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Re: TPI 350 Stalling

I'm also ordering an ALDL to USB cable + software and hopefully be better able to understand what's going on using my laptop.




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