I have a 2000 Chevy express 3500 with the 7.4 liter v8. It recently (2500 miles ago) had new fuel injectors, plugs, wires, and all O2 sensors replaced. Ran fine for a while, but now has service engine soon light on & shows codes p0131(O2 sensor) and p0108 (map sensor).

While stranded in the parking lot of Advance Auto Parts, I was able to replace the O2 sensor, but it still idles rough and will die when I put the automatic trans. into drive. Where is the MAP sensor located???

In an effort to get home, I unplugged an unknown sensor (i thought it was the MAP, but it has a round 3-pin connector which is different from the parts store images) and it runs and drives, but with a decrease in power. The sensor I unplugged was located in the intake manifold just after the throttle linkage. Can anyone tell me what I unplugged? It was held in place by (2) T20 torx bolts.

Thanks,

p.s. I'm new to Chevy stuff...I'm more of a Pre2001 Jeep guy...gotta love those XJ's!

 

Does anyone know where I can find a good parts diagram for the intake area??? (or anything that will help me identify parts/sensors connected to the intake manifold).

It turns out that I unplugged the Throttle Position Sensor...wonder why that made it run well enough to get home???

Thanks in advance

 

Because when you did that the computer used a preset number to mix fuel and air.

Before it was probably misreporting the position of the TPS and messing things up.

Time for a new TPS