OK well since I installed my Mac Headers everything has gone pretty well. Today I drove it to the exhaust shop with open headers and the y-pipe connected. I got a service engine soon light on all the way there, but i expected it since it was open headers because it never gave me any codes bfore the installation. The exhaust shop did an awesome job with putting a pipe inplace of the old cat. So now I have a complete 3in exhaust! But now to the bad part my car now runs like straright hell and I don't mean that in a good way. Like it won't idle at all when u first start it up and it smokes so bad (grey and black, mostly gray). And when u rev it up it can't make a steady idle it will surge and stumble. Also it feels like I have a 4cylinder in the car, NO power!. But after I drive it for a while 10-15minutes the SES light comes on and the car starts acting normal and then she runs like a bat out of hell. I really felt the gain in power! My next set of problems. When I was installing the headers I broke some sensors. I thought maybe the car would be fine but I guess its not. Well I first broke the nipple of the egr vavle and my vacumm line is just lying next to it. What should I do with that? Secondly on the passengers side I broke off the temp sesor on the ride side of the cylinder head near the headers. I am not getting any temp reading at all now on the dash. Thirdly their is a wire right off the O2 sensor . I'm not sure what it is, I thought it use to be grounded on the old exhaust manifold. But I just did this and when I pluged it in ,the temp gauge on the dash toped out like to 290 (off the scale). I;m pretty mad right now because I was so happy to get the car out and now this happens. If anybody could help please do so. If you need anymore information from me to help diaigonos the problem, please feel free to ask.
Thanks,
Cory Mohr

 

I think the wire right off the 02 sensor is supposed to have a little clip on it, this should attach to the temperature sensor sticking out of the block on the driver's side. This controls your in dash gage. I know because I did headers last summer, and knocked it off of the sensor which led to no coolant temp reading on the dash what so-ever. You need to get a new EGR valve, or plug that port at the bottom of the throttle body leading to the EGR solenoid, and buy a EGR block off plate or something. I'm sure having that vaccuum hose off is leading to some of your problems. The passenger side coolant temp sensor controls the engine fan, so you need to get that fixed too, or you'll be on the side of the road with a big puddle of bubbling coolant under your car. (Had that happen to me when my coolant sensor that controls the engine fan wasn't hooked up- overheating-not good.) I don't know about the grey/black smoke, but try fixing the other problems first. Did you have any smoke coming out before doing the Exhaust? How many miles on the motor?

 

Hey thanks for the information. I just just relized that the clip comming off the o2 sesor is for the temp sensor on the block, its just not long enough because the 02 is now located down on the y-pipe. So should I just plug the egr line and the sensor? Plus I don't think I need get a new fan sensor because I got my fans on a manual switch loacted in the car.

 

Plugging the vac line to the egr solenoid would be good, it should resolve some vaccuum leak issues, but I don't think having a non-functioning egr valve on the intake manifold is good, it might be OK. Maybe someone else knows for sure???

 

Need to leave the EGR system in tact. The ECM changes the fuel mixture based on how much it thinks the EGR is open. If the vaccume hose isn't hooked up your fuel mix will be off when the EGR is in use.

I would get the temp sensor hooked up as well as the O2 sensor, then unhook the battery to reset the ECM and see what you come up with.

 

I put my mac-headers on 2 weeks ago.

For the o2 sensor: I opened the plastic tube protection, tock the tape that holds the 2 cables of made the o2 sensor come out 5" earlier and fixed it to the tube all the way back.

The fan switch: http://rodneydickman.com/retail_new.html
I need to replace mine too, fell apart wen taking it of. Wen I turn my air-condition on the fan keeps turning and the engine never gets too hot.

Burnt plastic smelling smoke: the 3 straigt plugs caps slightly tuch the headers, once the tuching plastic melts back it does'nt tuch anymore and stops smoking after 2minutes
The starter wires are held wery close to the headers, I took the wires off and snapped the to the engine-side little metal lip of and tightened back up holding the wires closer to the engine
No wire or plastic should have direct contact to the headers or your going to have truble.

Always unplug the battery when playng with the wires.

My brother had his 92firebird that some days felt like it run on less then 8cilinders and it was a fried spark cable tuching the exhaust manifold.

Hope that helps.