Truck is running like its got a 4 cylinder in it. Its a 1989 w150 with the 318 TBI. I got under hood and looked at spray pattern, and there is no gas at all spraying from left injector, at idle or when accelerator is pressed. You can lightly tap on the top of the injector and a little spray will come out. Is this the injector or the TPS?? There are no codes except 12 & 55. Need answers asap, as this is my only way to go right now. Thanks in advance.

 

Injector is clogged, or failed. You can try measuring resistance across the pins, but, I am not sure what value is correct.

 

I replaced the injector, and it runs like a dream now! I had previously looked at the spray pattern and it was spraying, but would "cut out" every so often...then it got worse and completely quit spraying. This is the reason i had asked if it might be TPS.


Thanks for the help!