BlackS2

When I turn on my car, it sounds almost like a lawnmower, runs really lean, and I have to keep it alive by finessing the gas pedal. It also backfires incredibly loud every couple of seconds or so. I’ve tried doing some makeshift trouble shooting, but don’t really have access to the right tools. The MAF is good, I reset the ESS, but I don’t know what to do next. I’m thinking it could be a bad vacuum leak, or something wrong with the fuel pump / injectors? Not really sure, so any input would help, as well as how to go about checking whatever y’all think might be the problem. It is a 2010 MT with approx. 53k miles, new coils, new ngk spark plugs and wires, and never had a problem before.

200.mph

iTrader: (9)

how old is the ignition? ive had new coils fail right out of the box. do you have a cat?

Loki

iTrader: (1)

'Runs really lean' and 'backfires incredibly loud' are mutually exclusive. Backfires are fuel in the exhaust, so it's rich or not timed correctly. Is the check engine light on and are there any codes?
Did this start after any particular modification or work on the car?

BlackS2

literally just replaced them, and no I have a catless midpipe

BlackS2

it threw codes P0171 (Lean air/fuel ratio bank 1) and P2270 (HO2S12 signal stick lean) but not anymore. Now it just throws P2101 (Throttle control motor). It misfired randomly one day when I was driving and wouldn’t let me accelerate, so I popped it in neutral and it shut itself off. It wouldn’t start, so I replaced the coils, plugs, and wires, made sure they were all connected right, and it started but sounded really bad and backfiring so I just shut it off so I didn’t somehow cause any more damage. Do you think if I just keep it alive for long enough it will eventually stop backfiring and idle normally?

Loki

iTrader: (1)

I think you should bring it to someone who can examine it in more detail. There's only so much we can do over the internet. I don't think running it more wil fix it. A compression test wouldn't hurt. If you threw a seal, this would be one possible result.

Can you check if there's oil in the intake and clean it and the MAF sensor out if so?

Debi Carpenter Magee

In the beginning of my problems with my 2004, I had the same problem after replacing plugs, wires , and coils. It was the fuel pump ,which I had to replace twice because the mechanic broke the wire that gauges the gas.When I ran out of gas with a full tank, he insisted that one had nothing to do with the other. Even after I brought him a diagram he denied it. 2 days later he had to replace the fuel pump again and funny thing my gas gauge works.

BlackS2

do you mean it was the same thing as in the gauge not working or it running so bad?

FrancescoRX8

Hello guys, i got the same problem, the car stalls on idle and when i change gears and if i try to save it, it will backfire a lot, so wanted to know if you resolved it and if yes then how ? Thanks.