Checked that already when I first started having these problems. Hopefully I will be able to try a different PCM soon and see what it does.
Checked that already when I first started having these problems. Hopefully I will be able to try a different PCM soon and see what it does.
Anybody have any ideas on deleting the p0121 test and if it will solve the problem?
Mzoomora, disconnecting the TPS and reconnecting is not a valid test. It will see a new low voltage and consider that zero throttle angle. When you plug it back in it sees a higher voltage and thinks you have cracked open the blade. 20% TPS is high enough to add some IAC counts and not lower the engine speed to the desired idle. The PCM doesn't think the blade is shut. If you had this problem without actually disconnecting the TPS by hand, you have a PCM or wiring concern. I would look hard at the TPS connector, make sure all of the pins have not been mutilated, enlarged as to not make good connections. You also may have an intermittent wire connection at the sensor. Pull on all three wires and make sure they don't pull out of the terminal. Sometimes the vinyl casing is intact but the internal wire has broken. Also a short to ground in the 5 volt reference circuit or output of the TPS will momentarily pull the learned minimum TPS voltage to a new value which the PCM will learn as zero. This of course would not be real and once the real value comes back "short gone" it is at a higher throttle angle.
Good luck, Al
"Trash that carb and get Injected!"
Okay. Problem SOLVED!!! I did like foff667 said and disabled the P0121 test by raising the minimum and maximum map readings to run the test from 55/65 to 75/85. Took it for about a 20 minute test drive and it shifted fine.
Thanks for the help!
Is this C3904 and C3905...?
glad to hear you got it working right
joecar- Yes, those were the ones I changed.
foff667- It just took me a little while to figure it out. I had the car tuned and told him what to do, but he never got it right. I started doing some searching and figured out what parameters needed to be changed- worked like a charm.
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