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My roommate has a 2004 impala and it had died on him so he got it towed to a repair shop, he already had a check engine light on for a long time and knew what it was, 02 sensor. so when he took it to the shop that is what they found and replaced it. drove it home and it died several times on him. He showed me and it would hiccup and the rpm’s would bounce around and then it died. My wife has a chevy and awhile back it was doing the same thing and it had a really bad spark plug so it was miss firing,so I checked his spark plugs and they looked pretty bad, 2 even had what looked like a spider web in between the gap.So I replaced them and I let it sit for 20 mins and it was fine. when i went to test drive it, it hiccuped while accelerating once, maybe twice. Let it sit and it did nothing, even while in park and bringing up the rpms. drove it around the corner again and it hiccuped again and then when I stopped the rpm’s bounced around like crazy and almost died. gave it some gas and then it seemed fine.
so that’s where I’m at, any help would be very much appreciated. and the only other thing he could tell me is that some technician said that his battery was not working very well when they did a test on it i guess.
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oh I forgot, when i parked it and when to take it around the corner a second time it had died when i put it into reverse to get out of the driveway.
When you engage the transmission, it puts a load on the engine and aggravates issues like this. I would spray your spark plug wires down with water so see if you are arcing anywhere, Unless you have coil packs, then I would check for spark an fuel when its in gear (have someone in the car put it in gear and hold the brake)
status update, thanks for the help guys.
so i sprayed with water and didn’t see any arching, couldn’t find a vacuum leak anywhere. checked his air filter just to see and it was horrible, replaced it. running great although it is still hesitating when accelerating, did the transmission check that he had in one of his videos and it still did it. so i checked the fuel pressure and from the information that i found for its psi it was definitely below it. so we let it run until it made the rpm’s jump around again and the fuel pressure also went crazy along with it. possibly fuel filter, regulator or pump? thanks for any help very much appreciated.
changed it and it was still happening. and just another thing is that once we let it sit and warm up it will die after about 15 mins, battery light comes on but i feel that is normal. starts right back up but will hesitate while accelerating. but with the new fuel filter its still getting the same psi. should be 48-54 but its getting 42
You don’t have enough fuel pressure/volume to
run the motor.Did you check the fuel pressure
regulator? But if your not getting enough at
idle then you won’t have enough under load.Is there any other test I can do to ensure it is the fuel pump? And when I had tested it and it got to about the 20 min mark and the rpm’s started jumping around like it has been doing. The psi jumped around. Which it is hooked up right from the fuel line that then connects to the injectors then to the pressure regulator. So I would asume nothing else but the fuel pump could make the pressure change like that correct?
I havnt read here what engine you have, and there was 2 different engine codes (8th digit of the VIN ) around that year there was a TSB about the fuel pressure regulator
3.8 supercharged. There is vin 1 and vin k. So this is vin 1. I’m going to redo my fuel pressure test by the book exactly which also has me test the regulator.
You could also test your fuel pressure regulator by pulling off the hose that attaches and see if fuel squirts out of the regulator as the engine is running. Sometimes if they have a bad diaphragm it will suck fuel into the intake and make it stutter and stall.
so i tested the regulator today, it has no fuel in it i checked that the other day and it was still dry today. but it seems fine according to the test in the book. i couldn’t fully do the last test though where you attach the pressure gauge to the return line as i need to get some extra fuel line from somewhere if i want to do that. tried and i sprayed gas everywhere because i was using some rubber hoses lol. but according to the book it should be at a certain psi and then when the car starts it should drop by 3-10, it is actually going up by about 2-3 psi. and like ive mentioned before it is only acting up when the car warms up after about 15-20 mins. runs amazing up until that point. even drove it to the store and didn’t do it until on our way back. but this haynes manual doesn’t cover the information for the supercharged edition which this is. but according to information i have found online the psi while the car is in the on position should be at 48-54. for the none supercharged it should be at 53-59 in the on position. it is staying at about 40 psi now in the on position so its way below both of those. fortunately this Chevy has a area in the trunk to remove the pump unlike my wife’s car which i just did a couple months ago. damn Chevys and their fuel pumps lol…
anyway, now i have to convince him to spend the money on the pump and hope that actually is the problem… any other advice?
If the regulator isnt super expensive I would replace that too. They do tend to get worn out after a while.
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