Evil GT0

i have an auto 04 gto, this car is my baby and i recently installed pacesetter longtube headers.. after the install my car started idling very rough to the point of almost dying...(it actually died on me once)... i dont know what the problem could be and i was wondering if anyone could possibly help me. ive asked some of my friends and they said could possibly be the spark plugs/wires etc. so i changed all those out just incase so they are brand new.. another thing i heard is it may be the o2 sensors? im not sure but those are pretty new as well... anyways what happens with my goat is ill put it into drive and start to go... it will start shaking as the rpms build and then when it gets around 3-4k (depending how hard im on the accelerator) it will just clear up and jump forward.. and it keeps doing that. also when this happens the check engine light will blink for a second then stop. any help would be greatly appreciated, hope i explained the problem enough... oh current mods are only k&n intake, pacesetter longtube headers, and a diablo sport tuner.

EdgarB

iTrader: (2)

Happened to me when I installed my headers. Turned out the passenger side header was touching the harness and created a short.

Evil GT0

Hmmmm, I'll have to look into that. Appreciate it

Slickgoat05

bad 02's possibly. After i did my long tubes my o2's took a dump and i had the same idling problem. Fixed o2's and all was good.

409CISecondGen

iTrader: (2)

OK does this happen intermittently or all the time?

Evil GT0

Yes all the time, right when I start it up and drive. The weird thing is though (I know I probably shouldn't do it) but if I do a couple pulls on the highway like 1-3rd it clears it up after a couple runs and then it runs normal... Until I turn it off and back on again of course... I'm really confused with it :/

Robofuzz

You may need to have it professionally tuned.

409CISecondGen

iTrader: (2)

At WOT I think the ecu essentially ignores the O2 sensors. Open loop mode, it only listens to the maf and iat. So that could be your issue. If it were me I would try to pull the codes, if it was an upstream o2 sensor then that's probably your problem.

SJFGTO

A flashing CEL indicates a misfire, and that is not good. Check all wiring around the headers above and below. Run a scan and see if you are actually throwing a code. My gut reaction is you are running too lean with the LTs and your tune needs to be adjusted for the headers. A lean condition can cause a misfire.

outkast6991

iTrader: (34)

are you sure you plugged the front 02's into the front harness. years ago i had a shop install headers on a camaro and they used the rear 02 wiring to connect the front 02's. car ran horribly unless it was into PE (ingnoring the 02's)

Evil GT0

i pulled some codes. p0300/p0155. random misfire/o2 heater sensor circuit(front bank 2)

svede1212

iTrader: (3)

Check the front O2 connections. You could also have one that got damaged in the swap. DIY you could buy a new sensor and try it or have someone look at it that can scan and see what's going on otherwise it's just guessing.

PhantomGOAT

I'd also check your plug wires. When I had my pacesetters put in, the garage didn't plug one of my wires all the way back on the drivers side. It looked good to the eye, but it felt loose to the touch. Caused misfiring, a rough idle and threw a few codes.

jsmith309

Get a dyno tune. Then the shop that does it will tell u what u need if the tune don't fix it.

gconnoyer

iTrader: (1)

First off it needs a tune.
For testing though, flash your stock tune into the car and see how it behaves.

Secondly, I'd say a new set of front 02's. I put my headers on and before I got a chance to get it tuned, it ruined the front 02's in about 3 weeks. Whether it was actually from the running condition of the car or it was just their time I dont know. Just how it happened.

As far as the misfire goes. Pull the plugs and check the gap. Also check your wires. Check to make sure they are seated on the coil and on the plug.
I'd be willing to bet that one of your plugs was resting on the header and got cooked through.

GTOSE

iTrader: (1)

This ^

Did you use proper O2 extensions also?