Intermittent SES light after header install

[90K1/2ton]

Reset the computer and rechecked codes. Only getting code 12 ERROR CODE DIAGNOSTIC SYSTEM FUNCTIONING CORRECTLY .


I'll have to take her for a spin to see if the light comes again. Hopefully not. Thanks for all of your help!

 

[VCaddy]

Code 12 is what lets you know you've entered diagnostic mode. It's normal.

I occasionally see that code 32 with my long tube headers. There's not much you can do about it, the EGR system doesn't function well with a free flowing exhaust system. Here's some technical EGR reading - http://www.gearhead-efi.com/Fuel-Injection/archive/index.php?t-485.html

 

[Supercharged111]

I don't recall disconnecting any EGR hardware when I removed my factory manifolds. Is their a port in the head that I may have blocked or something? Thanks. I'll reset my computer today.

Thinking back, that was air pump garbage that was on my TBI manifolds (it's been a while). EGR is internal, isn't it? It's the Vortec that has the external EGR pipe coming off the manifold. Either way I got the code 32 on my TBI truck with long tubes but I also removed the valve and installed a blockoff plate. Truck seemed to be happy that way, my guess is because it knew the EGR system was faulty it never turned it on and switched the fuel/spark maps over which is what causes problems with an EGR that's been removed.

 

[VCaddy]

Yeah, TBI heads are internal EGR. The stock manifolds just had a heat riser for warming the intake.

 

[90K1/2ton]

Is a block off plate all that is required to delete EGR. Personally I'd rather remove it than replace it.

 

[VCaddy]

You'll need to disable it in the PCM also, unless you want the SES light on all the time.

 

[90K1/2ton]

Sounds like yet another reason to get into tuning....thanks!