4l60 shifting 400 rpm too soon as well as rev limiter dropped 400 rpm
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4l60 shifting 400 rpm too soon as well as rev limiter dropped 400 rpm
I recently got my car tuned and it ran great for a couple days and was shifting at 6700 rpm like it is tuned to do so, now for some reason it shifts around 6300. The car is not throwing any codes and the tps reads 99% when pressed to wot. What could be causing this? The only thing I did after the tune was pull the abs fuses because the car has 26s in the front and 28s in the rear.
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WOT uses a different shift table than partial throttle.
The % throttle for WOT can be tuned too. While I set it to 95%, perhaps your tuner set it to 100% and you are now only reaching 99%. The TPS generally has some adjustability; adjust it so that WOT gives you 100%, assuming the throttle really is opening all the way.
The % throttle for WOT can be tuned too. While I set it to 95%, perhaps your tuner set it to 100% and you are now only reaching 99%. The TPS generally has some adjustability; adjust it so that WOT gives you 100%, assuming the throttle really is opening all the way.
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The car was tuned with the 26s and 28s. I did notice one of the front speed sensor wires got loose and was hanging, could it be possible that it got damaged and is screwing everything up? Or does it matter since the abs fuses are pulled? I'm kinda just spit balling here cause its frustrating me cause it was running spot on and just changed overnight. I will also check the tps and see if I can get it to read 100%.
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I just checked a stock 2002 tune and the WOT shift tables are used at 94% throttle and above. It might be time to check with your tuner.
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one thing for sure you want to go by the obd2 datastream if your trying to dial in rpm or you will chase your tail , less on a more accurate aftermarket guage than the oem one but the pcm is going to command a shift based on the data its recieving from sensors such as crank position sensor
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So I gotta datalog it basically correct? Unfortunetly I dont have the software to do that...yet. I am working on it though. I've been messing with the idle set screw on my TB cause my tuner said they are notorious for moving and screwing things up. He told me to put lock tight on it, and like an idiot I didnt listen and took the car out, and I did notice it does move some cause I indexed it.
edit, also if it makes a differance my MAF is descreened, but it was done before tuning it.
edit, also if it makes a differance my MAF is descreened, but it was done before tuning it.
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Sorry to bump this thread. I noticed the upper shell of my fast intake is not sealed right, could this be causing my shifting problem? the 1-2 shift has dropped some again and I noticed my redline is at 7070. I belive it what set to be at 7200 but I dont 100% remember.