i have an 01 intrepid ive intalled a 3.5 ho out of an wrecked 300m

the thing runs fine except it keeps setting off a code 171 ,174 too lean bank 1&2 which it did today at the inspection station.
the engine was a known good engine out my old 300m . ive found one vacuum leak ,under the fuel tank fixed that ,and replaced the sending unit in it as well {since i had no fuel pressure holding inline}ive done just about everything i can think of and dont know what else to check ,
although yesterday it did stumble a little bit when starting it up but other than that it runs fine on the road.

 

you still have a vacuum leak thus the lean codes you are getting for both banks. Best way to check for hidden vacuum leaks is get a can of brake cleaner and spray it all around the intake manifold and plenum and see if you can find your leak. If you have access to a scanner, see what your Short Term & Long Term fuel trim numbers are. If they are both over +10% you have a definite vacuum leak.

 

alright ill try that out, i wasnt to sure how the fuel tirm readings were supposed to look like .

oh btw would runnig a 2.7ecu on a 3.5 engine set off a code?
dispite putting the 3.5 in, it still acts like a 2.7 .