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bigmikestud
09-13-2004, 14:10
Problems include: Hesitation at all RPM's (real apparent at 2400), sometimes throttle goes away on highway (then service throttle light comes on), turn key off and restart, light goes away and have throttle again. New FSD/Cooler last 5,000 miles to fix stalling. Can hear lift pump, changed filter, opened fuel valve by thermostat housing and it didn't stall. Now what?

Dvldog 8793
09-13-2004, 15:00
Howdy
Did you clean out the filter bowl? If not then you may as well put in another filter when you do. What code is coming up for SES? That might give you clue. If not, I would start with the least expensive fix. Filter(already done), lift pump, injectors, then IP.
Hope this helps!
L8r
Conley Janssen

Hye
09-13-2004, 16:06
Short answer. You might have a problem with the Accelerator Position Sensor. On my '94 the Accelerator P{edal Position (APP) module is located at the top end of the accelerator pedal rod, just afew inches from your foot.
Long answer. The APP has three sensors inside. The PCM compares all three. According to the book, if one fails the PCM will store a code. If two fail, the PCM will store a code and illuminate the STS lamp. If three sensors fail, the PCM will store a code, illuminate the STS lamp and reduce power to the engine. You may have kicked the connector. It should have a nine pin connector. According to the book, DTC21-23, DTC 25-26, DTC 63-65, for failure of one of the three sensors. DTC 84 isfor an intermittant APP fault, but this won't illuminate the STS light. DTC 99 is a reference voltage fault that will iluminate the STS lamp and reduce power.
APP's ain't cheap, I've seen them on ebay, but not often, and at GM they come with the pedal.

bigmikestud
09-13-2004, 16:51
I was hoping NOT to hear that as my '97 needed one too. It cost around $260.00 clams compared to this one at $340.00.I'm hoping he gave me list price on this one because I can't imagine the difference in years. n restarted but the problem is immediate. My FSD problem took awhile to happen and these symptoms are much different.

ttpost
09-13-2004, 17:23
ive never done it, but i have heard you can drill it out,being careful not to hit the wiring inside and spray electronic cleaner in it. i am sure someone who has done it can give you more information. good luck

Hye
09-13-2004, 18:01
I'd bet that the cleaner trick would be worth a try. The book shows them to be three potentiometers. Those clean up pretty easily if you can get to 'em. Just don't pull in front of any trains until you're sure its fixed.