Sr20det blacktop sputtering

[gumaheru]

Hi guys I need some help. I have a stock sr20det blacktop. The engine just started running like crap! It has a rough idle and sometimes backfires. It'll sputter while accelerating, for a hot second, around 2000rpms, it'll kick in like normal then start back firing and bogging all the way up through 5000rpms. After 5000rpms it'll run fine until I try to boost. Then it'll bogg and backfire again.

I installed an adjustable fpr and made sure that it is at factory settings. Changed the spark plugs. The plugs were clean and looked fairly new. I unplugged the o2 sensor to see if it made a difference. It ran a little rougher at idle with it unplugged. I checked the tps. All voltage was correct. I had to put it to .35 just to make the car run. The ECU isn't throwing up any error codes. I squeezed all of the little vacuum lines to see if there would be any difference in idle and nothing. I even pulled a couple of the vacuum lines to see if it would make a difference. It gave it a rougher idle. Also shook all of the hoses and re-clamped anything that looked like it might have been loosely secure. I also took some intake cleaner and sprayed around all the hose ends to see if I can get the idle to jump. Nothing.

I'm stuck slamming my head against the wall here guys. Without spending loads of money trying to figure out what is wrong, can anyone give me any suggestions?

[srstan]

make sure your getting spark to all of your coilpacks. i had the same problem.

[Vernal]

leaky injectors? timing? bad/dirty mafs? Any recent changes?

[gumaheru]

Don't know if it is a leaky injector. I'd have to pull it to check it. I cleaned the maf before checking the o2 sensor. No recent changes. I did pull the coil packs and saw that one is cracked. I am going to replace that this weekend. Then go from there.

[4-20sx]

sounds like its between MAF, spark plugs or coil packs.

had a similar problem. changed my maf and spark plugs. BAM car ran perfect.
make sureyour plugs are properly gapped also.

[gumaheru]

I changed out the spark plugs. I make sure that I gap them every time. I'll check the MAF after replacing the coil packs.

[shinobis13hb]

Maf maf maf!! While your at it get a AFR gauge!

[HIGHFIVEBETA]

MAF or coilpacks! the infamous sputter issue. it could be a # of things

[gumaheru]

Thanks for all of the responses guys. Turns out that the coil packs on the first to cylinders were bad. Replaced the first one, ran pretty good. Still a little crappy on acceleration. Replaced the second one. It started up, mis-fired then the idle automatically changed and it purred like a kitten. I have been driving it for two days now and no issues. Idles great and is actually quieter then it was before. Boosts no problem. I guess it was just that time. I've had the SR for 4 years now and I guess I need to start replacing things slowly but surely.