hey, its been a while since i posted, i have been having the floor boards in my trans am replaced, anyways, now that it is back on the road, i plan to tackle a second problem. The engine wants to cut out all the time, so i brought it to my mechanic, who hooked it up to a computer, and showed me that my sensors were reading that it was -40 outside, so the air to fuel ratio was off. He suggested that i would need to replace the computer/computer chip. I am not exactly mechanically inclined, but i do read these boards often, and i was wondering if he was referring to the ecm ( it is an 85 trans am, 305 LB9). And if there was someway to have it reprogrammed instead of replacing it entirely. I dont totally know if i have grasped that concept, as in if there is a relation between the computer he was reffering to and my ecm as i know it, so if someone could steer me in the right direction it would be greatly appreciated. thanks, mike.

 

I woul loook into trying to replace your coolant temp sensor, the one that the ECM reads, not the gauge sender, maybe try the wiring, make sure it's all hooked up right. It is one of the main senders the ECM uses to govern how much fuel to inject. If the reading is cold, it dumps a bit more fuel in to help it along until it warms up enough. If the sender is shot, your reading will be constantly low or high, depending on extreme high or low resistance. For your case, the sensor is reading the maximum resistance, which equates to -40°C.

I belive it's by the water neck, not sure though. Basically, is what I think is happening is the sender or wiring is shot, so the ECM gets a bad reading. The ECM constantly thinks it (the engine) is then running cold, so it dumps an excessive amount of fuel in. That is causing it to cut out.

 

hey stekman, thanks for your input, i just checked in my chilton's manual and it doesn't seem that difficult, so i think i'll try it this weekend. By any chace do you know about how much this part will run me if it isn't the wiring? Whatever it is, it has to be less than replacing the whole unit as my mechanic suggested, lol. Neways, thanks again, i'll let you know how it goes.

 

I second the CTS sensor. You can check one with a thermometer, volt meter, ice and a stove top.

The test values can be found with a search or three.

 

I third the above. $8.99 at autozone for my '88 305TPI T/A.. I haven't changed it (or need to), so I can't offer any experience, but that's what www.autozone.com lists for my car.

I'd assume you'd be best off by draining the coolant (or at least most of it) before removing the sensor, and make sure the coolant isn't hot..

Oh, and last piece of advice is don't drink the antifreeze