73-87chevytrucks.com

73-87 Chevy _ GMC Trucks => Performance => Topic started by: Tazman on November 07, 2011, 05:26:48 pm

Title: BACKWARD TPS
Post by: Tazman on November 07, 2011, 05:26:48 pm

My light went on so I checked the code (22) and it said low voltage to the TPS.When checking it I probed the b and c wires,with the closed loop the reading was 1.6 which I thought was not bad.What peaked my interest was when on open throttle it went down to .6 when it was supposed to go up to around 4.5.This TPS is not that old but if it bad it will the last one I get without going OEM.Let me know what you think.Thanks

Title: Re: BACKWARD TPS
Post by: VileZambonie on November 07, 2011, 06:14:51 pm

Hook your meter up in parallel and probe each cavity key on engine off. Report results

Title: Re: BACKWARD TPS
Post by: Captkaos on November 07, 2011, 09:05:55 pm

Just putting what I already said in here.....

....what cavity are you probing?

A = 0 when metered parallel to ground.
B = 5V reference
C = at idle (closed) the TPS should be set to .55V

If you open the throttle, the Voltage at C should rise from .55V upwards.

Title: Re: BACKWARD TPS
Post by: Tazman on November 08, 2011, 02:35:10 pm

Had a time getting this done but after all was said and done the reading I got was .2.Please let me know if there is an issue here.Thanks

Title: Re: BACKWARD TPS
Post by: Captkaos on November 08, 2011, 02:59:49 pm

Is this at Terminal C?  If it is .2V you need to adjust it (twisting the TPS with the bolts loose) to get .55V...

Title: Re: BACKWARD TPS
Post by: Tazman on November 08, 2011, 10:04:44 pm

But does this say anything about the readings on the TPS going backwards?

Title: Re: BACKWARD TPS
Post by: Captkaos on November 09, 2011, 03:31:41 pm

I am confused..  you are saying if you probe C and at idle it is at .2V and you open it, it goes to below .2V like .00001V?  Or does it move toward 5.0V?