Backfire's under boost and hesitation.. what could it be?

[BlueBeast22]

So I noticed this weekend while taking a road trup that under boost my car hesitated more than usual and I would hear backfires! I didnt hear any engine knock... just backfires. Now, I figured maybe its my spark plugs going bad? although I just changed them maybe 5k miles ago... And I did also just have the oil changed which shouldnt be causing problems. Also I did gas up at some random place while I was on the road. It said 93 octane gas but there's a good chance that maybe it was watered down or not even 93 octane. Could my car having turbo hesistation and constant backfires under boost be from having crappy fuel in the car?

Any help would be great.

 

[Fudgie]

I'd be looking at my intercooler pipes and connections first

 

[BlueBeast22]

I checked all of my IC connections, they seemed fine and I also made sure the clamps were on tight, which they all were. I did get some octane booster from the auto store and it actually did seem to help with the backfires... I only got one small one while under hard acceleration and the turbo seems to spool up fine. So maybe that was my issue?

 

[justa4banger]

Ignition, just cause you changed the plugs doesn't mean there aren't good. Also i would look at plug wires. Had a simliar issue with my other turbocar and it ended up being a bad wire.

 

[JCell]

check your spark plugs

 

[BlueBeast22]

Ok, I actually think the problem might have been one of my spark plug wires wasnt pushed down all the way... I havent had a backfire since but Im still going to replace my plugs with some ZFR7E-11 colder plugs.

 

[justa4banger]

I don't think plugs are needed. Most of the time it is wires, not plugs, unless they are old or exposed to pre-ign.
Also why do you think you need colder plugs?

 

[BlueBeast22]

Because im boosting around 10-12psi and colder plugs are what I usually run in the summer time.

 

[elmer1987]

my car also back fires but i thought it was normal for the vibrant setup. its not?

 

[shane02pro5]

It's common on decelleration and downshifts but not under accelleration.

Exhaust leak? I say run some seafoam thru your intake and see if there is any smoke coming from the exhaust manifold. I had a leaking threaded fitting for my Hiboost manifold for the EGR.

 

[BlueBeast22]

Nah, it's something else. I just ran seafoam through the car about a month ago... I usually do this every year to get the carbon build up out. It's gas related or ignition. After using the octane booster I havent had any backfires under boost. And I also made sure all of my sparkplug wires were on secure...

Now if it keeps it up after I get a new tank of gas and new spark plugs, then I will replace the wires... if that doesnt work then I will have to think of something else.

 

[Fudgie]

Any trouble codes stored or pending?

 

[BlueBeast22]

Nope, nothing. Still giving me some small backfires... from inside they sound very deep and muffled... so its not like a loud POP. I changed my spark plugs today, when I pulled them out they had like a redish brownish tint to them. Not sure why? maybe cause of the seafoam I used about 3 weeks ago? Anyways the car drives strong... and boosts fine, I just keep getting small backfires under WOT and full boost.

If a new tank of gas doesnt fix it then I will try the sparkplug wires next.

 

[shane02pro5]

The seafoam is the reason. It is known to foul out plugs and I always change mine right after. The seafoam has loosened alot of carbon and pieces are trying to make their way out. It may also cause a CEL. A day after my seafoaming once I was getting on it going into second at 12psi by the way and BOOM! Huge white smoke cloud covered the 2 lane street for like 5 minutes. Aparently a chunk of carbon made it's way out probably in the form of a fire ball. I usually put some 104 octane after the seafoam.

 

[elmer1987]

what is seafoam and where can i get it, mine backfires when accellerating slowly.

 

[BlueBeast22]

Got some Heet today from the auto store, I havent had a backfire yet... But then again im about to fill up the tank with new gas so hopefully this little problem is over.

Seafoam is pretty much an cleaner you put in your gas tank, oil, and let some of it get sucked up through your pcv valve while the car is running. It cleans the motor and gets rid of carbon build up. Works great.