Dathan

I bought a 1997 Mustang that the head gasket was blown. I changed out both head gaskets and every gasket that was in the gasket kit. After I finished the job a 0171 code came up. I removed and tested the O2 sensors and they check out fine. I cleaned the MAS and checked it with a meter and it is fine. When I scan the engine the bank 1 sensor 2 is reading 0 volts. The engine is running with a bad miss and when I remove the spark plug wire on #3 cylinder the engine doesn't chang where if i remove any other plug wire the car tries to stall out. I have removed and installed new o-rings on the injector for that cylinder, cleaned it too. I did notice that the little cap was missing during the new head gasket rebuild. The plugs and wires are new with less than a few miles on them, test drives. The spark plug to that cylinder is black and the others still look new. Could this issue be causing my lean code? Also does anyone have a clue what's going on with that #3 cylinder? Could this also be why bank 1 sensor 2 is reading bad? Thanks for the help.

PNYXPRESS

Retrace all the wiring checking for pinched wires, loose connectors, and/or fraying.

Daehawk

And change that plug. If it still read bad Id consider changing the coil.

jwog666

you should check for spark at that plug with a spark tester, if you have spark, then test for injector pulse with a noid light at that injector connector, if that passes, then check compression on that bank, the suspect cylinder should be within 10% of the others. remember in order for the cylinder to fire it need 4 things 1 spark, 2 fuel, 3 compression, 4 for all of that to happen at the correct time. when you say head gasket was out, does that mean it was burning coolant? if so you may have hydro locked that cylinder and bent a rod slightly, this will lower the compression ratio and cause a missfire.

Dathan

Found the issue. The wire going to the injector was shorting out. I replaced the wire a the codes cleared, runs great. Thanks for the help.