Expy lunging forward when starting
#31
03-20-2003, 11:21 AM
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Originally posted by bridge
Blue,
My first post to this thread (see above) asked about a similar problem while in traffic; for example coming to a stop at a light, in gear with foot on brake. My problem does not happen in park, so I think that Jim was suggesting an idle problem which I guess could over-power a light brake pedal.
Blue,
My first post to this thread (see above) asked about a similar problem while in traffic; for example coming to a stop at a light, in gear with foot on brake. My problem does not happen in park, so I think that Jim was suggesting an idle problem which I guess could over-power a light brake pedal.
#32
03-23-2003, 10:31 PM
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All I know is that these 5.4L’s are very quirky. Mine operates perfectly about 99% of the time, but I had to replace the IAC valve at around 50K miles and then shortly thereafter I experienced the sudden rapid idle phenomenon. It happened after I left work one evening, so the engine wasn’t completely up to operating temp. I was at a stop light when my RPM’s shot up and the truck wanted to move forward, inasmuch as I only had light pressure on my brake pedal. I, however, completely agree if the brakes are “firmly” applied, then no amount of throttle will move the vehicle. I’ve since reset the PCM and have not experienced the lunge again.