TPI Misfiring
#1
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Car: 1989 Trans Am GTA
Engine: 5.7L 350 TPI (Deleted Cats)
Transmission: 700r4
Axle/Gears: Original 3.27
TPI Misfiring
So, my GTA has been misfiring when its humid outside, I noticed that a plug wire was burned slightly and exposed, I thought that it would be the issue, so I changed all the plug wires and while i was at it i changed the plugs, that day i started it up and it ran fine, jump foward a couple weeks and its doing it again. Its most noticeable when you lay into the throttle, any help in diagnosing the problem would be great.
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Car: 1989 Trans Am GTA
Engine: 5.7L 350 TPI (Deleted Cats)
Transmission: 700r4
Axle/Gears: Original 3.27
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Car: 1989 Trans Am GTA
Engine: 5.7L 350 TPI (Deleted Cats)
Transmission: 700r4
Axle/Gears: Original 3.27
Re: TPI Misfiring
All Acdelco, i used dielectric grease on all the wires. Ill check for a burned wire in the morning but I doubt it, i spent 30 minutes routing the new wires to make sure they didn't touch anything.
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Car: 1989 Trans Am GTA
Engine: 5.7L 350 TPI (Deleted Cats)
Transmission: 700r4
Axle/Gears: Original 3.27
Re: TPI Misfiring
Possibly, the car did sit for awhile. Im going to replace the filter this coming weekend, car sat for 10ish years and we replaced the filter once back in 2014. Hopefully its that, if not then injectors is my next thing. Any way to test them without removal?
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#9
Re: TPI Misfiring
A hot/cold resistance test is one check which can reveal a failing solenoid, and Multec injectors are prone to that. However, it doesn't provide any information about clogging, sticking pintles, poor spray pattern, or other injector flow problems.
Given the intermittent nature of the symptom, linked to high humidity, I'd thoroughly check the ignition system first. Don't overlook the coil.
Given the intermittent nature of the symptom, linked to high humidity, I'd thoroughly check the ignition system first. Don't overlook the coil.
#10
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Car: 1989 Trans Am GTA
Engine: 5.7L 350 TPI (Deleted Cats)
Transmission: 700r4
Axle/Gears: Original 3.27
Re: TPI Misfiring
A hot/cold resistance test is one check which can reveal a failing solenoid, and Multec injectors are prone to that. However, it doesn't provide any information about clogging, sticking pintles, poor spray pattern, or other injector flow problems.
Given the intermittent nature of the symptom, linked to high humidity, I'd thoroughly check the ignition system first. Don't overlook the coil.
Given the intermittent nature of the symptom, linked to high humidity, I'd thoroughly check the ignition system first. Don't overlook the coil.