A few weeks ago my evap purge solenoid on the intake manifold went bad. Then last wednessday (1-9-12) my map sensor crapped out on me. My car was running horrible (rough idle, intermittent limp mode, terrible fuel trims (ltft 30%)), but when I replaced my evap purge solenoid last thursday (1-10-12) most of these problems went away (ltft went down to about 18%, no limp mode, smooth idle). So I ordered a new map sensor (the one on the intake manifold) and it came in today so I replaced it. From 1-10-12 to today I drove my car everyday with a blown map sensor and it was running pretty good, now today after I replace the map sensor the car is back to going into limp mode intermittently.

My main question: How can my car run fine except for a ltft of 17% with a blown map sensor and now it is back to running bad with a brand new map sensor? This makes absolutely no sense to me.

 

Double digits equal no good, lol, especially with that much added (correction for) fuel. 5% +/- is usually the norm. I'd check for vacuum leaks. Boost leak test with soapy water, use carb cleaner (on a cold engine) or propane to run against the mating surfaces. You'll find the vacuum leak when the rpms rise. I would find that leak that's causing your whacky fuel trims.

PS You're the "cat" guy, right, hahaha?!

 

Yup, haha, nothing but bad luck.