OK on my 01 Bravada I normally drive a short distance to work on mostly flat roads with no issues. However when I hit the interstate the truck feels a bit sluggish and when I go up long hills recently have started getting a flashing check engine but no discernable miss, and now a P0101.

Again it feels sluggish but no discernable miss. Any thoughts? I'm struggling to find a situation in the search function that is like mine, but may have missed one.

 

Sounds like a leaky injector

 

Interesting....I hadn't considered that....all my research seemed to point to a partially blocked cat (284k on the original cat)...

 

sorry after rereading i correct myself. Does your truck have spider injectors? and the code is for the MAF

 

What do your fuel trims look like?

Have you done a fuel pressure leak down test?

Since you suspect a plugged cat you might consider a back pressure gauge test.

George

 

So a lot happened after this post and I am just realizing I never got back to it. I wanted to provide a conclusion. Shortly after this I got hit with tones of OT at work and had no time to do any of the suggestions, so I took it to a local shop that the family trusts. After some work they determined it was, in fact the cat's. The precat was 75% blocked and the main cat was even worse. So much so, that the flowmaster 40 series on it was quiet until the cats came off, and then it was MUCH louder to say the least.

Since KY doesn't do emissions testing, we installed a straight pipe in the place of the cat, and I had a turbo muffler installed like a resonator in front of the flowmaster and the sound is great now - good rumble but nothing deafening.

To avoid the resultant O2 sensor code which occurred with no cat, I purchased an O2 sensor 90 degree extender and spacer from Amazon for $10. This pulled the sensor out of the main flow of exhaust and it works great - no code since it was installed.

Now on the interstate I have great power and no more p0101 codes on inclines.

Sorry for the LONG delay in replying.