Surging in OD
#1
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Surging in OD
I just drove an hour and a half down the shore and i noticed that my car surges a little in OD while cruising. I hooked up my scan tool and watched the torque converter slip rpm. When it'* not surging, the slip is around 9 but when it does surge, the slip variesfrom -9 to 25. Also, this dosen't happen while accelerating in OD.
I tried to check he fluid but i don't think i'm getting a corect reading because my rans dip stick tube is pretty bent. The dip stick actually gets caught while it'* comming out and theres air bubbles in the level holes with fluid going past them.
Any ideas what'* goin on?
I tried to check he fluid but i don't think i'm getting a corect reading because my rans dip stick tube is pretty bent. The dip stick actually gets caught while it'* comming out and theres air bubbles in the level holes with fluid going past them.
Any ideas what'* goin on?
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When the surge is occuring, is the torque convertor locked up? This should be readily available info on the scan tool. If the torque convertor is still locked up and it is surging, is it the engine RPM going up and down or the vehicle speed? We need to narrow the problem down to engine or transmission. Any codes?
#3
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Originally Posted by A Bonnie Canuck
When the surge is occuring, is the torque convertor locked up? This should be readily available info on the scan tool. If the torque convertor is still locked up and it is surging, is it the engine RPM going up and down or the vehicle speed? We need to narrow the problem down to engine or transmission. Any codes?
The surging goes away if i accelerate slightly. The torque conveter slip then goes to about 30 rpm (torque converter is still locked up).Then shortly after i go to light throttle/cruise the surging comes back.
When i was using the scan tool on the way down the shore it had a historic code. It said run pndl(i forget the 4 letters exactly) switch failure. But when i went out to go look at the code agian it wasn't there according to the scan tool.
I hope i'm being clear enough. If there is any more info you need just let me know.
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Update:
My idle is really bad now too and the engine now spudders from idle through 2k rpm.
The more throttle i give it te better it seems to feel. (ignition voltage??bad coil/icm???)
So maybe ignition related???
My idle is really bad now too and the engine now spudders from idle through 2k rpm.
The more throttle i give it te better it seems to feel. (ignition voltage??bad coil/icm???)
So maybe ignition related???
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I played around with my injectors today to see if it changed the idle.
The car ran noticibly rougher when i unplugged each injector seperately except for the center one on the rear bank. I watched the lt fuel trims as i unplugged each injector and they increased fast except for the rear center one. The tl fuel trims did increase but not as fast as the other 5.
I checked the coil terminals for rust but they were all clean.
Should i do the coil resistance check??
The car ran noticibly rougher when i unplugged each injector seperately except for the center one on the rear bank. I watched the lt fuel trims as i unplugged each injector and they increased fast except for the rear center one. The tl fuel trims did increase but not as fast as the other 5.
I checked the coil terminals for rust but they were all clean.
Should i do the coil resistance check??
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So, on my way home from work, i stop at a light and my idle gets even worse. The engine was running real rough and it sounds like one of the coil packs went by the exhaust note.
I swaped each coil out with a spare one at a time but the engine still ran real rough.
Since i'm loosing oil, does anyone think that a have a real bad oil fouled plug? Could a spark plug get bad enough to sound like the engine is running off 5 cylinders?
I swaped each coil out with a spare one at a time but the engine still ran real rough.
Since i'm loosing oil, does anyone think that a have a real bad oil fouled plug? Could a spark plug get bad enough to sound like the engine is running off 5 cylinders?
#7
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rpm
sounds like you may have a clogged injector or ignition problem.
I would pull the plugs and inspect them, check the spark plug wire resistance.
Maybe add fuel injector cleaner and check injector pulse on the scan tool.
I would pull the plugs and inspect them, check the spark plug wire resistance.
Maybe add fuel injector cleaner and check injector pulse on the scan tool.
#8
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I'd be thinking plug or wire. Just last week Lilhoov had a problem, tested his wires with an ohm meter and found them to "test" good. However 1fatcat mentioned the problem with testing them. How do you test something that'* carrying a normal 30,000V load with an ohm meter?
Was a valid point and once the supposedly good wires were swapped the car ran great.
Something to think about. Maybe do a similar test w/the plug wires by removing one cylinder at a time. It'* the old school method of looking for poor spark. I'm sure Napa sell the plug tester light that you can put in line between the wire and plug.
Was a valid point and once the supposedly good wires were swapped the car ran great.
Something to think about. Maybe do a similar test w/the plug wires by removing one cylinder at a time. It'* the old school method of looking for poor spark. I'm sure Napa sell the plug tester light that you can put in line between the wire and plug.
#9
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light
I have that test light and it works well. Pulling one plug wire at a time is a good method of finding a bad plug or wire but you have to insulate your hand well from sparks. I don't recommend doing this as you can easily burn or shock yourself.
#10
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Would an ignition problem account for slip in the TC? Maybe there are two different problems going on here? I ask because I've been a victim of the "surge" for a while, yet I have intermittent misfires as well.
I hope you're able to connect the dots on this one. Other'* (like me) have had limited success tracking these problems down. Use that scan tool to its fullest potential for monitoring your TC.
I hope you're able to connect the dots on this one. Other'* (like me) have had limited success tracking these problems down. Use that scan tool to its fullest potential for monitoring your TC.