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DISCUSSION => General Topics => Topic started by: Johnnypjr on September 02, 2017, 09:32:16 PM

Title: Backfiring and hesitant throttle
Post by: Johnnypjr on September 02, 2017, 09:32:16 PM

Hey everyone. Super new to this so I hope I'm in the right place. I have an e30 318is and I keep having a backfiring/hesitation when under heavy acceleration. I replace the cps, checked for all vacuums leaks, cleaned the air flow meter. I replaced with a known working iac, kinda stumped atm. I don't know if I should start look towards fuel pump. Fuel pressure regulator  seems good. I'm just out of ideas.

Title: Re: Backfiring and hesitant throttle
Post by: bmwman91 on September 07, 2017, 01:53:31 AM

How do the spark plugs look? How about the spark plug wires?

Title: Re: Backfiring and hesitant throttle
Post by: othatseric on September 11, 2017, 10:20:58 AM

Have you tried replacing the fuel filter?

Title: Re: Backfiring and hesitant throttle
Post by: colin86325 on September 12, 2017, 10:34:25 AM

Backfiring points to unburnt fuel. I'd suspect the ignition system, possibly the coils.  Test them with an ohm meter.

Title: Re: Backfiring and hesitant throttle
Post by: Johnnypjr on October 26, 2017, 06:57:11 PM

I ended up replacing all coils, didn’t fix the problem. Then while looking down after replacing all of that. Turns out one of the wire had a rub mark on it and I guess it was ground out. I fixed that and started running great! Thanks for all the input!

Title: Re: Backfiring and hesitant throttle
Post by: colin86325 on October 27, 2017, 12:26:47 PM

Awesome, glad you got it sorted!