ok so here is my problem. when the car is cold it starts ok, cranks for a bit but it sputters and starts up. after driving for a while and getting the car hot it wont start. example: lets say im getting gas. i turn off the car while its fueling which is what about 5 min or so. its a safe assumption that the motor and everything is still warm at running temp. When i go to restart the motor it cranks for one revolution or two then while still holding the key to start it the starter gets really slow like if the timing just advanced itself 30 degrees and is making it jump. so if i try to crank it over the starter slowly is unable to turn the motor until it cools down then it spins it ok.

SO im thinking either its a ecm issue or my starter is just a pos and cant spin the motor like it should be able to and when its hot it just gets worse. all the sensors on the motor are new with the exception of the esc aka knock module. Even the dizzy is new, it has a new GM module, pickup coil, cap, rotor. The only thing that is old is the Ignition coil.

another side note... I have a autometer tach installed along with the stock one in the dash. every now and then the needle jumps from about 1200 where its idleing up to 1500 then up and down erratically. its not consistent tho it only does it on occasion. i heard somewhere that the coil is bad when that happens?

 

i would start with grounds....i had a similiar problem on another car when hot, turned out to be the battery ground wire

 

Sounds to me like your starter is getting heat soaked or just plain dying.

 

yeah im thinking that as well... it was a cheap autozone special from a few years ago and a few motors... its def taken a beating thats for sure.

 

any one else have any ideas?

 

yup, the heat soaking is probably an issue. Are all of your exhause heat shields in place? I had the tach issue aswell - when my factory tach would do that the ecm wasnt getting a good ground. I could tell because I had an ammeter grounding the ecm in addition to it's grounds and when the tach jumped so didnt the current on my added ground. However, Autozone's testing said my coil failed the test. I have also read that this may be due to electrical interference from the dizzy.

 

I have had this starter on this motor with headers last year when it was a carbed motor. ive only had this problem with the tpi. the motor does get very warm but shouldnt be anything major, temp stays under 220 while driving without a fan.

as far as the tach im pretty sure its the coil, its pretty old and im not even sure how many miles are on it.

 

Well, if it is the coil... You gotta wonder if that bad signal is only going to the tach or if the coil is actually firing like that... and also if the computer is getting the same bad tach signal for injector signaling..

 

I thought the fuel reference signal came from the pickup coil?

I know the computer really needs a tune, i just dont have the money right now. Some days it runs better than others but when it runs right it smokes the tires into second easily. I dont think im going to mess with it too much without a computer data logging it this way i can see where im going and what not instead of guessing.