Q: 04 explorer 4.0 soho po171

asked by on March 23, 2017

Bought truck non running,found broken rear timing cassette.I pulled the motor bought the expensive cam alignment set and everything went well changed all the chains and cassettes.put it back in it fired right up but runs quite rough and only code on it is a po171 fuel trim lean on bank 1.Checked for vacuum leaks pulled the intake and valve covers rechecked the timing,all good.Compression on bank 1 is 170,165 and 170.

My car has 101000 miles.
My car has an automatic transmission.

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