Idle woes, misfire upon deceleration, HELP!!!
#1
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Idle woes, misfire upon deceleration, HELP!!!
Hey
Alright so with my 87 gxl, there was some MAD backfire... when shifting... when idling... most of the time (before the rebuild anyway).
With my 89 T2, i think i narrowed down my idle issues to raw fuel being dumped. Symptoms:
1. Rev in neutral, not too high, let drop a couple hundred rpm... popping/misfiring upon decellaration... random... all sorts of stuff
2. Rev in neutral between 1000-2000RPM (and hold accelerator steady), popping/misfiring can be heard... very random
3. Very hot days, very hot engine... idle stumbles and engine sounds like this RAT TAT TAT *fart* RAT TAT TAT *fart* RAT TAT TAT *fart*, and the idle surges between 500 and 750 rpm, unless you keep the idle up with the accelerator. This particular issue dissapears after 10 seconds of driving.
Now I've asked this over and over, but i havent been able to solve the problem yet. I JUST got back from checking the TPS, and testing for leaking injectors. TPS is perfect, injectors are perfect.
Tested so far: BAC, Injectors for leakyness, TPS (OVER AND OVER AND OVER), spark plugs, timing, coils, vacuum leaks.
Left with: AFM, Split air solenoid, Anti afterburn valve.
OH YES. One more thing... if the AC is on, issue #2 is almost nonexistant (i guess because the bac is allowing more air)
Alright so with my 87 gxl, there was some MAD backfire... when shifting... when idling... most of the time (before the rebuild anyway).
With my 89 T2, i think i narrowed down my idle issues to raw fuel being dumped. Symptoms:
1. Rev in neutral, not too high, let drop a couple hundred rpm... popping/misfiring upon decellaration... random... all sorts of stuff
2. Rev in neutral between 1000-2000RPM (and hold accelerator steady), popping/misfiring can be heard... very random
3. Very hot days, very hot engine... idle stumbles and engine sounds like this RAT TAT TAT *fart* RAT TAT TAT *fart* RAT TAT TAT *fart*, and the idle surges between 500 and 750 rpm, unless you keep the idle up with the accelerator. This particular issue dissapears after 10 seconds of driving.
Now I've asked this over and over, but i havent been able to solve the problem yet. I JUST got back from checking the TPS, and testing for leaking injectors. TPS is perfect, injectors are perfect.
Tested so far: BAC, Injectors for leakyness, TPS (OVER AND OVER AND OVER), spark plugs, timing, coils, vacuum leaks.
Left with: AFM, Split air solenoid, Anti afterburn valve.
OH YES. One more thing... if the AC is on, issue #2 is almost nonexistant (i guess because the bac is allowing more air)
#4
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go pull out your injectors and get them cleaned and balanced. Give me a shout after you have done said above and if tha didn't help check your anti burn valve.
#5
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Try using a garden hose instead of propane. I had a idle problem suddenly appear 2 weeks ago. If I had gone looking for a vac leak with only propane or carb cleaner I would never have found the leak.
One or both of my primaries are leaking, probably at the insulator(s). I found this b/c when I ran the hose over the TB she'd bog. But never anywhere else and I ripped apart and re-did the TB joints so I knew that that wasn't it anymore.![Smilie](https://www.rx7club.com/images/smilies/smile.gif)
Try a hose and slowly go over everything.
One or both of my primaries are leaking, probably at the insulator(s). I found this b/c when I ran the hose over the TB she'd bog. But never anywhere else and I ripped apart and re-did the TB joints so I knew that that wasn't it anymore.
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Try a hose and slowly go over everything.
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#11
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So you were going to check for a vacuum leak using water while the motor was off?
Lessee, ya put that there hose inna teh AFM and then crank teh water on full and then watch teh motor to see where teh water comes out...
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LongDuck
1st Generation Specific (1979-1985)
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10-07-15 08:12 PM
383, 89, accelerator, chev, decceleration, decel, decelerating, deceleration, engine, holding, misfire, misfiring, missing, random, slight, steady