OK Guys - here's one I have not seen anyone on here suggest. ddog73, do you get your gas at the same place all the time and what octane do you buy? I have tried the gas at my local Costco 3 different times, and every time the truck would run like s#@t. I even had it shudder and die at a few stop lights. Possibly if you fill up the same place they have crappy gas???? This might explain why it runs better when you spray a more combustible fluid in your TB.

 

Not sure if this helps, but I had something very similar happen in the '70 Mach 1 Mustang I used to have. It would run for about 20 minutes, then die. Turns out, it actually was the coil. What was happening is that it operated fine until it reached a certain temp (usually could run good for 15-20 minutes). As the temps increase, apperently so does the electromagnetic field created by the coil. Once the coil got hot enough and the field was big enough, the coil would arc to the nearest metal object, causing the car to sputter and eventually die. I replaced the coil, and relocated it slightly (away from the place it was arcing to), and that took care of it.

I have also been told the same thing can happen with plug wires once they get hot enough. If that was the case, you would see similar symptons as the ones you described - runs good for 10-20 minutes until it heats up enough to cause the problem. Make sure your wires are not touching any hot surfaces, and check that your plug boots are in good shape.

 

I'm confused now. Did you say it ran fine until it warmed up or ran bad until it warmed up?

 

no it runs like crap for the first 10 mins or so. After that it runs great.

Thanks Dan

 

Ok, that clears it up. I think others were confused on that matter. My final guess is either your injectors are not working properly or your throttle body isnt opening enough. Either too rich or too lean for it to run properly. Then when it gets hot, the O2 sensor kicks in and adjusts the air/fuel mixture.

 

that right because the O2 sensor wont tell the Computer what to do tell it is warmed up. my injectors all test fine. cleaned the TB about 3 times. but still does not mean they are working good enogh i guess hmmmm.....