RPM fluctuating
05-11-2015, 09:11 PM
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Car: 1987 Camaro LT
Engine: 305 5.0 LG4
Transmission: 700r4
Axle/Gears: ?
RPM fluctuating
Hello! My RPMs just stated fluctuating the other day out of nowhere
It mostly happens in fourth gear but also happens in third. Never first or second. I will be on the highway in fourth in overdrive going about 65 at 2k rpms and they will drop to about 1500 or a little higher for about 3 seconds and go back up to 2k for about 20 seconds then back down. I first thought the tranny was slipping but someone mentioned it could be the MAF. I have 700r4 with a carbed LG4 305 on a 87 LT camaro. I cant seem to find the MAF
Any ideas?
It mostly happens in fourth gear but also happens in third. Never first or second. I will be on the highway in fourth in overdrive going about 65 at 2k rpms and they will drop to about 1500 or a little higher for about 3 seconds and go back up to 2k for about 20 seconds then back down. I first thought the tranny was slipping but someone mentioned it could be the MAF. I have 700r4 with a carbed LG4 305 on a 87 LT camaro. I cant seem to find the MAF
Any ideas?
05-26-2015, 09:27 PM
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Car: '88 Iroc
Engine: Single turbo Vortec 5.7, Megasquirt
Transmission: Probuilt 700r4 3000 stall Vigilante
Axle/Gears: Moser 9" 3.25 w/True Trac
Re: RPM fluctuating
A carburated car won't have a mass air flow sensor. Sounds like the torque converter is unlocking and/or it's downshifting back to third.
06-30-2015, 09:45 PM
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Car: 1987 Camaro LT
Engine: 305 5.0 LG4
Transmission: 700r4
Axle/Gears: ?
Re: RPM fluctuating
A carburated car
won't have a mass air flow sensor. Sounds like the torque converter is unlocking and/or it's downshifting back to third.
won't have a mass air flow sensor. Sounds like the torque converter is unlocking and/or it's downshifting back to third.I have been running the car for a while now without addressing the issue.
the car will run fine for a day or two then the fluctuations will come back all of a sudden. I found a vac leak the other day and plugged it. this has helped a bit. my feeling is that there may be another vac leak somewhere else i still need to plug. is a vac leak something that could potentially cause this?
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09-26-2015 04:29 PM