HELP!!! Spitting,Sputtering, and Backfire???

[gsturbo91]

Ok, this is what's up. I have a 1991 Eclipse GS Turbo(FWD). Here in the past week or two it has been backfiring on me at WOT in mid-high RPM's. Well the day before yesterday it started spitting and sputtering(more like popping). This happens sporatically all the way up the rev range. The first thing that came to mind was the fuel pump. I have been running 15-16psi on it with no wiring upgrade. Could this be it? It is what I'm leaning towards, but I want to know all possibilites. Car was tuned up less than 5k ago, so I don't think its any of that, and it has a new fuel filter. I always run 93 octane in it , but I do run it real low sometimes.
Please Help, it's my daily driver.

Thanks All,
Justin

P.S.-This is making me !!!

 

[98TsiAWD]

Pull your spark plugs and check the gap, It seems NGK plugs only last about 5-10k miles in a DSM that sees boost often.
I put 7k on mine, gapped to .028, and they were worn as high as .045

 

[rookieupgrade1]

Don't rule out a bad MAS. It will cause similar simptoms
(I forgot to hook mine up last night. Took about 10 sec to figure that out)

 

[1990TSIAWD]

I also have that problem but I get a clicking in what sounds like a relay behind my stereo. At first I thought it was my ecu but i feel the relay clicking if i put my hand on it. please help!

 

[rookieupgrade1]

There is a relay there above the ECU I forget what it is for. I found them at the bone yard. $5 No one goes to the bone yard for relays

I tried swapping that relay when I had these problems then went ahead and changed the MAS cause the kid that had it befor me hacked it the wrong way.

 

[1990TSIAWD]

Well then it all falls together because the person that had the car before me has both honeycombs out and the filter is squeezed on without an adapter plate. I have a 2nd gen mass air on the way hope it works thanks

 

[gsturbo91]

Thank you 98TSiAWD that was exactly what it was. They were up to between .045-.048. This is why I love this place, you can learn by others experiences.

Thanks again man.

 

[cowan]

I just wanted to say thanks - my car started doing the same thing last night. I found this post and my spark plug gap was off. I would have replaced my plugs and wires but thanks to this post I only had to fix my plug gap.

 

[sarge]

yes, that fixed my problem too, i was having that BS burble and popping/hesitation, thought it might be plug wires, or fuel issues, but nope, just one plug was out of tolerance

 

[ChaosAgent1157]

ok...im having similar issues, but it only "pops in the middle of the rpm range (4500-6000 rpm) then pulls hard and smooth to redline. can't see anything on a datalog, and the plugs are clean and the gap is good across the board. any thoughts?