GMC code?

[tempest455]

OK, not a Pontiac motor but at least GMC.

I have a V-2 trim Vortec blower on a '96 GMC Yukon with a 5.7L for towing. This kit comes with an additional fuel pump, regulator and "Code 103 Buster" (adjustable frequency modulator) to help w/ the fuel curve in a blower application. Initially, it ran great without any problems and I towed 1,000+ miles without any problems.

Suddenly, it started running very rough and very rich (visible black smoke). It fouled a set of plugs and was showing a P0101 code. I checked the instructions and found that the "Code 103 Buster" did not have to be installed unless the blower was making more than 6 lbs boost. It would never be that high in a low RPM towing application for me.

Since then, I disconnected the Code 103 Buster and the additional fuel pump to see if that was the problem. It runs much better but is still showing a P0101 code. Strange why it suddenly started running bad. Bad MAF? Or, does the added air from the blower confuse the MAF?

Any code experts w/ blower experience???

[hugger]

did you ckeck the o2's? have you checked for leaks[vac/boost]? If the o2 sensors are coated with carbon they will really mess things up and the more coated they become the more fuel they will require. Jim M.

[tempest455]

I did not check the O2's yet. I did pull the MAF and it was coated w/ carbon. I blew it off w/ ether and will take it for a test and see if that helps. Next step will be the O2's.

Thanks.