I recently just bought an 89 dodge ram w150 318/727 auto 122000 miles throttle body injection, when you stomp on it it'll cut out and stall, sometimes not to bad and other times very badly, I' ve heard that it could be the throttle position sensor, but I'd like to hear your opinions, I own an 83 dodge, but the TBI is a little new to me.

 

Do you have a good manual? There are voltage tests for the TPS. It could be the problem or not. Is the idle and timing set correctly? Is the ISC (idle speed control) working?

 

Thanks for the advice, I do have a manual, I'll try it as soon as I can.

 

Well, I tested the voltage of the TPS and it is at 4.2 which the book says is ok, the ISC is working properly, I checked the fuel filter, and still acts up, the only thing I have left to check is the timing.

 

The feed voltage to the TPS is not a test of the TPS but should be 5 volts. The slow steady change of voltage out of the TPS with no gaps in that voltage as you open the throttle is the test for the TPS. With the throttle closed the output voltage should be 0.5-1.5 volts and should increase to 3.5-4.5 volts steadily and smoothly with no drop in voltage as you slowly go to full throttle.

You can also check the injector spray patterns. Look down inside the throttle body. There should be a fine cone of fuel from both injectors with no gaps or streams. The cones should reach the sides of the throat. Low ambient light and a flashlight will show the cones best.

 

The O2 sensor will cause the same problem. Check connector at firewall on right side of engine and at sensor. Connect a diagnostic tester and check output of O2 sensor if you can use one from your local autoparts store.

 

I will do that, I've moved the timing around and got better mileage and power so far, but something it's got and has had before i timed it was this kind of puff or pop, and sometimes a spitter or miss, the oxygen sensor being bad would explain that shouldn't it?