Hey guys,

we did a group by with the BC Corvette Club with LG which decided for me to buy my headers earlier then expected. We started late last night and was finished early today. Went very smoothly except once we started it up.

We did:

- LG Motorsports Super Pro headers
- NGK Iridium IX Spark Plugs 0.040 gap
- MSD Plug Wires

Current Mods:

-Vararam Intake
-B&B PRT mufflers
- *NOW* LG super pros

Basically what happened was we got the code reader and it was telling us that we were getting a misfire in 4 and 6, sometimes in 5 or another number. The hesitiation was really bad. Air Pump didnt line up on passenger side at all so we took the relay out. Swapped the coilpacks to see if that was the issue and it wasn't. Tried switching the new wires we got and wasnt that. Tried switching spark plugs and it wasn't that either.

We were thinking with the different location of the front O2 Sensors being further down compared to the stock manifolds it was sending wrong info to the PCM? Maybe just needs a tune?

Also we closed off the Air pump flanges on the LG headers. Air pump system is completely disconnected and plugged up (just in case) Would it be because the AIR system isn't hooked up that is causing this rich running and misfire? I wouldn't think it would cause that?

Thanks for any input and if I missed any information let me know so I can fill you in. Really bummed my weekend out with a car meet tomorrow that I'll be missing out on

Cheers!

 

From what I have seen, the most common problem when it is running badly after a header install is the 02 sensors have been swapped around. Left to Right etc.

 

I put the rear O2s onto the front since the fronts weren't long enough to get to the front o2 bungs. I just got the adapter that switched the front clip to the clip that attaches to the rear o2s that I got with the LG motorsports header kit. I took them out and switched the sides and it made no difference. Thank you for the first response and info!

So they are the Rear O2 sensors, but using the front O2 clips to switch the PCM seeing it as a front O2 sensor now. maybe plugged up? is that possible?

 

 

O2 Sensors were in the wrong bungs. Switched and runs much better, waiting on my buddy's computer to see if the misfire is still there.

Rookie mistake :P

 

Make sure you get it tuned!