car hits 4600rpm and POW, backfire and shuts off???
#21
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If my reluctor wheel is loose and is causing this problem with my car, do you know if it will it be loose enough to move around with one finger pressing it??
I removed my crank sensor and could easliy feel the reluctor wheel and I tried for 20 minutes to move it around the crank, and I tried to move it axially along the crank and it would not move at all.
John
I removed my crank sensor and could easliy feel the reluctor wheel and I tried for 20 minutes to move it around the crank, and I tried to move it axially along the crank and it would not move at all.
John
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Hey guys...I installed my buddys 1999 PCM with his H/C tune into my car. I wanted to see if my car would backfire and shut off with his PCM. Well, the car would "cut out" at the same rpms that my car would backfire and shut down at. BUT using his PCM, the car would not shut off. It would stay running. what the heck?
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Wow, really the only thing left then is the wiring... Unless you have some kind of mechanical problem that only manifests at that RPM like a broken valvespring ? If it backfires wouldn't that be an open valve that shouldn't be open ? Check valvesprings/pushrods lately ?
Have you checked ground wires where they meet the chassis/block/heads ? Is the battery mounted securely ? Anything moving around in the engine compartment when you hit the throttle that could be shorting something out ?
Just some thoughts...
BTW I'd still get the crank relearn done. Maybe the tuner can log what's happening when the car shuts off ?
Rob (Bad30th)
Have you checked ground wires where they meet the chassis/block/heads ? Is the battery mounted securely ? Anything moving around in the engine compartment when you hit the throttle that could be shorting something out ?
Just some thoughts...
BTW I'd still get the crank relearn done. Maybe the tuner can log what's happening when the car shuts off ?
Rob (Bad30th)
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Wow, really the only thing left then is the wiring... Unless you have some kind of mechanical problem that only manifests at that RPM like a broken valvespring ? If it backfires wouldn't that be an open valve that shouldn't be open ? Check valvesprings/pushrods lately ?
Have you checked ground wires where they meet the chassis/block/heads ? Is the battery mounted securely ? Anything moving around in the engine compartment when you hit the throttle that could be shorting something out ?
Just some thoughts...
BTW I'd still get the crank relearn done. Maybe the tuner can log what's happening when the car shuts off ?
Rob (Bad30th)
Have you checked ground wires where they meet the chassis/block/heads ? Is the battery mounted securely ? Anything moving around in the engine compartment when you hit the throttle that could be shorting something out ?
Just some thoughts...
BTW I'd still get the crank relearn done. Maybe the tuner can log what's happening when the car shuts off ?
Rob (Bad30th)
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Maybe a shot in the dark,But if you know someone w/EFILive you have to add to table {6101} ETC Predicted Airflow.I don't know if your PCM has that,But you can give it a try.I had the samething when I started modding.................Paul
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Hey guys...I installed my buddys 1999 PCM with his H/C tune into my car. I wanted to see if my car would backfire and shut off with his PCM. Well, the car would "cut out" at the same rpms that my car would backfire and shut down at. BUT using his PCM, the car would not shut off. It would stay running. what the heck?
This is the bit that got me confused , "BUT using his PCM, the car would not shut off" , maybe it is the the yank english
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Has fuel pressure been checked at the cutout point , what does the scan tool show when its cutting out
#34
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Fuel pressure stays at 58psi the entire time. The dealership said since my car is so modded and has a custom tune, their scan tool would not read correctly.
Im taking to the guy that dyno tuned the car to see if his software can see anything.
could bad coils be a option????
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I seem to remember reading something in HPtuners that torque management can be adjusted to cut out more or less cylinders when approaching abuse level. Maybe yours has all cylinders enabled to cutout at full WOT.This would account for shutting down with your PCM and only cutting back with your friends. Could have made that mistake when it was tuned. When I get a chance I'll get into my help section and read up on it. I doubt it would be your wiring if it's not doing the same thing with your friends PCM.
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I seem to remember reading something in HPtuners that torque management can be adjusted to cut out more or less cylinders when approaching abuse level. Maybe yours has all cylinders enabled to cutout at full WOT.This would account for shutting down with your PCM and only cutting back with your friends. Could have made that mistake when it was tuned. When I get a chance I'll get into my help section and read up on it. I doubt it would be your wiring if it's not doing the same thing with your friends PCM.
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...and it only happens when you're WOT to 4600rpm, but you can rev to that RPM from idle ?
Have you double-checked the coil and injector wiring ? (or did you install the new harness ?)
Do the lights/gauges in the car do anything wierd when it cuts out ?
Rob (Bad30th)
Have you double-checked the coil and injector wiring ? (or did you install the new harness ?)
Do the lights/gauges in the car do anything wierd when it cuts out ?
Rob (Bad30th)
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I would lean towards possibly a bad PCM since you said you shorted a wire on the CPS harness on the positive of the battery, the PCM can't take that kind of current directly to it.
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If i go into the throttle easy, this wont happen until 5000-5500. If I jump on the gas, it seems to happen around 4500. But yes, I can drive the car normal and take it to about 3000 and shift in to the next gear like normal.
Im swapping my buddys coils & wires on tonight. If my memory is working right, This problem occured after I found 2 cracked plugs and then I installed 8 new plugs. Maybe I screwed up a wire.
I bought wiring harness off a guy and found out it was for a '98 and wouldnt work with my car. I sent back and got my moeny back.
I know the gauges die out when the car shuts down. From what ive been reading this means the problem is electrical and not a fuel issue. Fuel pressure is at 58psi anyway.