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PKRWUD · 08-09-2001, 07:09 PM

Actually, my first thought while reading your description was a dirty MAF, but who knows. Are there any codes? Try disconnecting the TPS from the harness and hooking up the leads from a DMM (with a bargraph) across the VREF and TP Sig (grn & orange) wires. Set the DMM at ohms, and watch the bar graph as you turn the throttle. There's a good chance that you will find a flat spot, where the bar momentarily stops progressing, or even back steps. I had that happen with my truck, and when I tested it for a smooth voltage increase, it wasn't as evident as it was testing it for resistance. My bar graph jumped significantly in both directions while I slowly rotated my throttle. I replaced the old TPS (only had 60k on it!), and the problem was solved.

Good luck!

Take care
~Chris

------------------
Retired Moderator
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[This message has been edited by PKRWUD (edited 08-09-2001).]

08-09-2001, 07:09 PM	#3
PKRWUD Junior Member Join Date: Mar 1999 Location: Ventura, California Posts: 8,981	Actually, my first thought while reading your description was a dirty MAF, but who knows. Are there any codes? Try disconnecting the TPS from the harness and hooking up the leads from a DMM (with a bargraph) across the VREF and TP Sig (grn & orange) wires. Set the DMM at ohms, and watch the bar graph as you turn the throttle. There's a good chance that you will find a flat spot, where the bar momentarily stops progressing, or even back steps. I had that happen with my truck, and when I tested it for a smooth voltage increase, it wasn't as evident as it was testing it for resistance. My bar graph jumped significantly in both directions while I slowly rotated my throttle. I replaced the old TPS (only had 60k on it!), and the problem was solved. Good luck! Take care ~Chris ------------------ Retired Moderator MustangNet My site: JimPorterRacing RACECAR spelled backwards is RACECAR HEY !!! Are you ASE Certified ??? If you are, ask me about iATN. The best tool you'll ever have, and it's free !!! [This message has been edited by PKRWUD (edited 08-09-2001).]