TPS HELL, someone help me!!!
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TPS HELL, someone help me!!! Ok, i am having serious idle issues and ive narrowed it down to my TPS. I checked the voltage on it, and it reads .57 before i start the car. When i start the car it jumps to .63 which equals between 2 and 3 % throttle, so in other words my car is hanging at about 1800 RPMS. I have allready replaced the motor, and have tried the whole reset deal.
Can anyone please tell me how to reset the TPS, and if that is not the problem what should i look for next?
Anyone who has had this problem please chime in,
Thanks
Chris
Can anyone please tell me how to reset the TPS, and if that is not the problem what should i look for next?
Anyone who has had this problem please chime in,
Thanks
Chris
Assuming you correctly reset the TPS, you need to check the female connector itself and make sure it's making a solid connection to the TPS sensor. Check the small metal pins inside the connector to see if they are spread apart too much. You should double check the connector for the correct voltage with a Digital multi meter (DMM).
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I have allready done both, can someone please explain the correct way to reset the TPS?
The TPS reads correctly before i start the car, with the key in the on position. I think it may be a short, because sometimes it reads the proper voltage.
The TPS reads correctly before i start the car, with the key in the on position. I think it may be a short, because sometimes it reads the proper voltage.
I believe your TPS position is marginal, 60mV is not
much to make a difference but it's either side of the
.600V that distinguishes idle from open throttle. Do
you have the blade jacked open with the stop-screw?
You can file the TPS sensor holes with a rat-tail file
(tangential to the mounting circle) and make the TPS
adjustable somewhat, do this and set it with a DMM
reading until you see 0.50V at idle and it should be no
worries.
As to why the 60mV jump, I'd suspect a ground fault
somewhere, perhaps from the block and chassis and
PCM grounds not being all tied tight anymore. Losing
one of the ground straps is a possibility, so is just
having one come a little loose or corrosion.
much to make a difference but it's either side of the
.600V that distinguishes idle from open throttle. Do
you have the blade jacked open with the stop-screw?
You can file the TPS sensor holes with a rat-tail file
(tangential to the mounting circle) and make the TPS
adjustable somewhat, do this and set it with a DMM
reading until you see 0.50V at idle and it should be no
worries.
As to why the 60mV jump, I'd suspect a ground fault
somewhere, perhaps from the block and chassis and
PCM grounds not being all tied tight anymore. Losing
one of the ground straps is a possibility, so is just
having one come a little loose or corrosion.
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I think both of the situations you stated are probable. I have allready tried to manually adjust my TPS censor by widening the holes, but that did not work. I would think that if the problem was a ground fault it would cause more problems than just the TPS censor. I will check my grounds again.
I allredy tried the screw, and have it adjusted to about negative 1%, and it still wants to read .63V. I have ruled that problem out, so i think somehow the voltage it getting changed from somewhere other than the TPS censor. It seems like every time I upload a new tune the idle changes in this manner. I know it is not because of the variables I have changed since the TPS is a direct reading of the throttle position.
I allredy tried the screw, and have it adjusted to about negative 1%, and it still wants to read .63V. I have ruled that problem out, so i think somehow the voltage it getting changed from somewhere other than the TPS censor. It seems like every time I upload a new tune the idle changes in this manner. I know it is not because of the variables I have changed since the TPS is a direct reading of the throttle position.
The TPS will adapt somewhat to the voltage as
delivered, tries to set an idle / closed throttle to
"get along". There have been posts about this
(can't remember the key phrases, though, so it
might take some searching skill & patience).
I think the raw voltage is where it's at. It would
be worth measuring the block to PCM reference
ground voltage difference one time, stopped and
started. The TPS should be all referenced to the
PCM ground but something appears to be pushing.
If you've gone to -1% readings by screw adjusting
then the blade was jacked, and may still not be
seated. What do you read if it's seated mechanically?
If you see the holes allowing some adjustment but
not enough, maybe try a little more hogging. Maybe
just take the screws out, rotate the TPS housing
and watch the meter, make sure that the TPS -can-
produce a lower voltage at some angle. Also worth
checking that the TPS feed voltage (5.0V) and TPS
reference (0.0V) are showing sensible values relative
to some other PCM ground that's "independent" of
the problem area.
delivered, tries to set an idle / closed throttle to
"get along". There have been posts about this
(can't remember the key phrases, though, so it
might take some searching skill & patience).
I think the raw voltage is where it's at. It would
be worth measuring the block to PCM reference
ground voltage difference one time, stopped and
started. The TPS should be all referenced to the
PCM ground but something appears to be pushing.
If you've gone to -1% readings by screw adjusting
then the blade was jacked, and may still not be
seated. What do you read if it's seated mechanically?
If you see the holes allowing some adjustment but
not enough, maybe try a little more hogging. Maybe
just take the screws out, rotate the TPS housing
and watch the meter, make sure that the TPS -can-
produce a lower voltage at some angle. Also worth
checking that the TPS feed voltage (5.0V) and TPS
reference (0.0V) are showing sensible values relative
to some other PCM ground that's "independent" of
the problem area.
