Help Engine Surge

[Cheska]

I plan on scouring the archives later; but is there anyone who could let me know where to begin looking for the cause of an engine rpm drop and surge? I've got 14,800 on the truck and this has never happened before: I finished climbing a mile long grade, went on for about a 1/2 mile, then went to pull into a fuel station. As I pushed in the clutch and went to neutral the engine rpm dropped to about 400, then back to about 850, then back down... it kept repeating this cycle until I "blipped" the throttle, then it settled back down to a smooth idle. All this time, I never shut the engine down. I just let it idle for a few minutes while I filled my gas can, then headed home, where it repeated the same drop in rpm cycle as before at the fuel station. It did it again as I clutched going inito my driveway. Blipping the throttle stopped it in every case. Any thoughts?

dave

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2001 driftwood 5spd 4x4 2500 reg. cab

 

[Steve Campbell]

Well I have a thought. Have you checked the lift pump out put pressure on the engine side of the filter? Maybe a VERY dirty filter or faulty pump of erratic electrical supply. I am probably way off base here and the "big" boys will respond shortly to show me how far my foot is in my mouth.

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1999 Qcab 4x4 Driftwood
Lets move election day to April 16th Steve

 

[Guest00]

Could be your TPS.

 

[Cheska]

Thanks for the answers. JNutter, what is a TPS. Sorry, I just remembered: throttle position sensor. I'll have a look.