Shifting at 6k rpm, why???
#1
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Shifting at 6k rpm, why???
well i found out my pcm is messed up a couple days ago when my high speed fan wouldnt cut on. well i thought, no big deal as the car will only get hot when i turn on the a/c and its only getting colder. but i had the shop change my shift points from 6k to 6600. well when i was getting onto it i noticed the car is still shifting at 6k. oh also my ses light is on from my left o2 sensor going bad from mixing in some 110 octane gas a while back. would the ses light cause it to shift early as a safe mode or do you think my computer is causing the issue?
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Patience, Grasshopper. Like, we aren't all here full time despite
appearances.
Some things like a messed up TPS voltage at WOT (>4.75V)
will cause short shifting as a fault protection.
Tachs are notoriously laggy, and 6000 indicated might easily
be 6500 in reality especially in 1st gear where it runs up
quick.
A scan tool would be your best way of figuring out whether
it's a tach error or a real short-shift. You could measure TPS
voltage with the blade to the stops, if you have a voltmeter.
appearances.
Some things like a messed up TPS voltage at WOT (>4.75V)
will cause short shifting as a fault protection.
Tachs are notoriously laggy, and 6000 indicated might easily
be 6500 in reality especially in 1st gear where it runs up
quick.
A scan tool would be your best way of figuring out whether
it's a tach error or a real short-shift. You could measure TPS
voltage with the blade to the stops, if you have a voltmeter.
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A scanner log would definitely help, the actual bin from your pcm would help as well as I've seen instances where the customer has told the shop "please up this table by xx" and the shop never did it so it could be anything from they didn't do it to the tach being off to anything in between. Without more information theres not much accurate info we can give you towards an answer.
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thanks jimmyblue, i dont have a scan tool or a voltmeter but ill tell the shop to check that.
foff667, i wish i had more info but thats all i have. thank you for the input guys. ill let you guys know what the shop says.
foff667, i wish i had more info but thats all i have. thank you for the input guys. ill let you guys know what the shop says.