just dropped cleaned and put clean fuel into the tank of my 2001 pontiac grand am, had been sitting for awhile and recieved advice to clean old old fuel out of the tank as it was not starting up and staying on, and when it did it would run very poorly misfiring and would audibly struggle to stay on. Now after doing so the car started and was running noticably better idling at a proper level and was not struggling to stay on, we shut off the car for a moment and when trying to start it back up the engne began sputtering wheezing popping and backfiring and refused to start at all in fact, battery was low and died while trying to start up, recharged over night and tried again the next day the car started and began running fine parked, when revved though it suddenly sputtered popped and the engine died again, would turn over but not start up sputtering and popping again. advice? (spark plugs wireset are brand new, fuel pump turned out to be also new when we dropped the tank as well or atleast not worn out)
Try starting the car. Check battery voltage. Is it low again? Your battery may have low capacity and needs to be replaced. Sitting is hard on batteries too.
I’d be willing to bet you have clogged fuel injectors that need manual cleaning and/or replacement.
How long is awhile and why?
So you dropped the tank, cleaned it, and decided to reuse the fuel pump, because it looked good . . . ?!
And just how long was it sitting . . . ?!
If the fuel in the tank smelled rancid . . . then everything inside the tank should have been replaced. I’m talking fuel pump, fuel sending unit, sock, and so on
it was sitting since 2017 before it was given to me as a gift by my cousin, near the end of last year. it was being used by my cousins uncle before being left to sit at his house due to several problems. the known problems we found after it was given to me and what my cousin said, the uncle used a dirty oil can to fill the collant reservior (we flushed and cleaned all that and replaced the Reservoir) spark plugs were stock from 2001 completely destroyed and wireset (replaced) A fuse problem maybe? the first day i got the car i cleaned it out and found new and used fuses scattered about everywhere. we have used the scanner which is reading multiple misfire
im not a mechanic nor even partially knowledgable about car, according to those helping me the pump looked just as good as a new one including the filter on it, we did change the fuel filter thats about it when we dropped the tank. the car was sitting since 2017 before being given to me as a gift by my cousin. Also im on a very tight budget and time limit for getting the care up and going so replacing everything is not an option.
There are times when you fix some things and something else just falls apart. Now you need some luck. The easier thing to check would be the EGR valve which may be stuck open. More involved is valve timing if its a chain. Maybe easier than the belt. Then there are ignition leads which are often put back wrong. I found it helpful on the Quad four engine to see the picture of the engine which immediately suggested wrong wire placement. We went to the car and made it look like the photo and his car worked perfectly. Then he said 'don’t tell the wife." Happiness started to happen.
The Quad four doesn’t have plug wires