Installed long tubes won't idle
 

I just installed SLP tuned length headers on a 99 trans am and the car seems like it has a miss and won't idle. I deleted the EGR and I don't have the Y pipe connected yet. Any information would help. I really need my car

Need some more info. Did you install new O2's? Did you do a tune-up (plugs & wires)? Did you disconnect the battery? If so this will cause an idle relearn. Did you double check all the plugs and plug wires? Check everything that you touched on the install to verify that all is well.

Just some ideas.

Dave

Yes I disconnected the battery. While I was driving it felt like it was misfiring every once in a while and even stalled at a stop light. I did give it a tune up with TR55 plugs gapped at 50 and new wires. No I did not put new O2 sensors but the car ran fine before.

Could it be the rear O2 sensors not in the Y pipe yet and hooked up?? How long does the computer take to learn itself after the battery has been disconnected? It also hasn't thrown the check engine light. Please help, I need the car tomorrow. Thanks

Well if you are running open headers and stalling coming to a stop it may just be fresh air sucking back in on the O2's. I ran open headers to the muffler shop but that was only a mile or 2. I do not see any reason for the rear O2's to cause a miss. I have had them disconnected with a light for 5,000 miles. I would check all the plug wires. Remember the coil clicks twice and the plug boot once. Just check the simple things. Seems to always end up being something simply.

I checked the wires and they are all fine. It is running incredibly rich and is blowing black smoke, surging rpms and stalling out. Any more info I can check out would help. Thanks

You are running rich because when you run open headers you suck too much fresh air back into the O2 sensors. The computer thinks your running too lean so it will start dumping fuel to cure this.

Fact is, if you check your LTRIMS you are probably around +25 to +30 on both banks.

The longer you run like this, the more damage you will do to your motor. To rich of a fuel mixture will trash your plugs first, your O2's next, and if you wait too long, you'll wash down your cylinder walls as well, causing a bad smoke trail on decel.

DO NOT RUN OPEN HEADERS WITHOUT AT LEAST A 12" EXTENSION PAST THE O2.

*Rant off*

sounds like a plugs/wires problem. I would check that first.

mine would barely idle at all the first time i fired it up .... gotta give it a minute or soo then turn it off and back on

My car ran fine after installed my headers.. I would definately put the damn ypipe on it and then go from there..

:werd:

Thanks for everyone's help. Put the Y pipe on and it started running a little better. Checked the plug and realized it was fouled out already. Cleaned the plugs up and now it seems to be running fine. :hail: