QuestionQUESTION: When I crank my truck i hear the fuel pump prime and it cranks an runs fine. But sometimes it seems to lope an almost die but idles back up. When I'm driving it and let off the gas i can see my rpm gauge drop below the idle rpm the raise back up. I'm not sure if its the Fuel pump reg., pump, filter, sending unit or what. Sometimes after a quick run to the store an back when you kill it and come back it want even prime the pump at all and not start up. Like it loses vacuum or something maybe and also its more prone to all this in warmer temperatures. What your suggestions on this sir? Thank you Matt Peloquin
ANSWER: Matt, if you can hear that the fuel pump is not priming at times, then you may have a bad fuel pump. Now, the fuel pump relay can also cause this problem. Do you have a check engine light on? If you do, then I would suggest you take it to your local parts store and have the code read. You might find that the "lope" is being caused from a idle air control valve, throttle position sensor or a temperature sensor. But like a said, if the fuel pump is not priming (you turn the key and do not hear it buzz) this is a symptom of a bad relay, pump or loss of ground. Let me know if you have anymore questions. I hope this has helped, Jason
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QUESTION: I changed my fuel filter and also the station I filled up at last closed its doors so bad gas may have been it. I've went to the local parts house for that dino but they want do it unless the check engine light is on but, I'm going 2 try another one. Also I notice that the rpm drop and rise happens. Once I let off the gas and my truck decelerate it occurs at the down shift of the transmission. Now the transmission in the year model is known to go bad at anywhere from 120,000-175,000 so I've been told. In town I drive it in D instead of OD except wen on the hwy. I'm Going to get that transmission. flushed and cleaned run some new gas threw go get a dino done and go from there. Any other suggestions you may have I would be grateful of and THANK YOU VERY MUCH FOR doing this
SINCERELY,
Matthew L. Peloquin
AnswerMatt, after reading your last statements I would be more inclined to believe that the idle change is coming from the transmission. You are probably noticing it a bit more because the transmission is wearing out. I would certainly recommend changing the fluid and filter. Hopefully that will help a bit. And yes, that transmission is not a good one. If it doesn't have a cooler on it, I would suggest installing one on it. Good luck, Jason
