Pulsing power at slow speed when hot

[shum]

i have experienced a strange situation a couple times on my 97 SOHC - drive at slow speed, maybe 10 mph, (California freeway speed) the engine speeds up and slows down when throttle is opened just enough to creep along. Opening throttle more and engine responds normally. This has happened after some high speed driving and in warm weather.

Anyone have an idea what might be happening?

 

[MrShorty]

After reading the "adjust your TPS" thread, I wonder if it could be related to that. At that small of throttle opening, the computer hasn't recognized that you've opened the throttle and is trying to control the engine like it's at idle.

 

[Glacier991]

Shorty, mightn't the EGR do that if there's an intermittent problem there ? (thinking to all the DPFE problems). The idea being the EGR opens just slightly and acts like a vacuum leak, then closes, etc ? Just a thought. Might want to put a vacuum gauge on her and watch it in those situations. (I have some LONG tubing I keep handy JUST so I can watch vacuum in the cab in just such situations.)




Happy Exploring

Chris

 

[shum]

Thanks y'all. This has happened only twice in the last year. I might try the vacuum gauge idea.

I looked for the 'adjust the TPS thread' but can't find it.

 

[MrShorty]

Try searching for "adjust TPS". It came up #2 when I did it.