98 gt running like crap !

Jackinyourbox · Aug 31, 2016

I own a well maintained 98gt with 35000 miles . I just installed pi cams and intake and new ngk plugs about 50 miles ago . It ran fantastic ... For 50 freaking miles ... Now it sputters on take off . And when I go WOT it sputters so bad it sounds like a damn machine gun .and makes a puffing sound at idle . And definitely don't have the power I once had . It's Embarrassing .No check engine light is on or any other light . Here are the things I did in hopes of fixing the problem .
-new fuel filter
-new cool packs
-new spark plug wires
-all injectors are running (maybe one is plugged up idk)
-no gas odor coming from exhaust
-fuel pressure is at 32psi with key on 30psi running
-starts up fine no problems .
Been struggling with this for a damn week!
Many help would be appreciated .
thanks

PinkieT · Aug 31, 2016

Vacuum leak?

96blak54 · Aug 31, 2016

PinkieT makes alot of sense. The computer cant pick up a vac leak.

Here is my suggestion. Go unplug the maf and then take it for a drive. Report back.

Jackinyourbox · Aug 31, 2016

I'll give that a shot tomorrow and get back .
thanks

Nighttrain · Aug 31, 2016

Great suggestion guys, thats exactly what i was thinking when i read he did a pi swap. One other thing, did you tune it? Try unplugging the battery for 30 min to clear and reset.

Frank.JD.Perez · Aug 31, 2016

I'm just here for comic relief... I would be freaking out if it sounded how you described but then again my misfire issue was kinda similar

Burninriverdiver · Sep 1, 2016

I had similar issues after doing my pi intake and cam swap and the guys above are leading you in the right direction. Mine turned out to be several vacuum leaks... Check all those plastic vacuum lines (they tend to crack if you breathe on them too hard) and really check the rubber hose that plugs into the back of the throttle body/plenum, mine was dry-rotted and cracked causing a major leak. Good luck and let us know what you find

Jackinyourbox · Sep 1, 2016

Ok guys . Didn't have time to do much to night . And no nighttrain it isn't tuned. I did start it up and it has gotten ad enough and triggered my check engine light and it was the P0300 code . Random or multiple misfire , which I guess a vacuum leak can cause . I did start checking some vacuum Lines . The one coming out of the plenum isn't to bad . End of line is showing some small signs of dry rot . Started spraying carb cleaner over some lines. But didn't get a rise in rpms. I guess I'll check plugs and more lines tomorrow .ugh . Fml

Jackinyourbox · Sep 1, 2016

Didn't have time to get it out for a ride with maf unplugged . What would I notice from that ?

lwarrior1016 · Sep 2, 2016

Do you have a compression gauge? Maybe the cam timing is off, or the cam sensor is bad.

When you pulled the timing cover for the swap, was the tone ring (reluctor ring) behind the crankshaft sensor in good shape? Sometimes they get play in them or break and cause funky timing/running issues.