trouble shoot this please.

ok first off. I bought this 215K mi. 96 prism from a co-worker. this car had starting problems for his kid. He said it would start and run fine 1 time and the next it would crank without starting, after cranking for (10 min.) he said he could get it started.

When i went to get the car it started so i drove it home, before i shut it off i sprayed a lot of carb clean down the TB. it seemed to me that was the culprit, the check engine light even turned off every now and then(enough good starts). The car did however seem VERY sluggish below around 3500rpm, got poor mpg (20-21) shift at much lower than redline, and idled choppy. i changed the plugs, wires at this point.

After 2K miles and 3-400 trips the car wouldn't start. I sprayed start fluid down the tb and no start so i know fuel is not the prob. I have a shop manual, under "cranks but no start" i followed directions. I tested out the ignitor which has its 12 V on 1 pin, ground on another, but on pin 3 (harness side) is supposed to be 4-6V. I was getting 12V. The manual says to replace ecm at this point. I did, now the ignitor sees 5V at pin3. but it still didnt start. i had it towed home. Now it will start so the intermittent prob. is not present. The cam sensor (in distributor) reads correct ohms. The iat is infinate ohms, wont disable an engine though. At this point im stumped especially since i cant replicate the no start right now.

Also the MIL i cant get to flash.

Anytime it cranks good but won't start, check the basics. Have a helper crank it, while you visually check for spark at the plugs. If you have spark everywhere, use a gage and check fuel pressure. Around here some of the national brand autostores used to check OBD2 codes for free. They also used to loan out a fuel pressure gage, if you don't have one.

thanks for the response.

the car was broke down in downtown. so time was short. when the motor cranked but no start it didn't fire at all on any cylinders, it cranked at a consistent speed. with the starting fluid it didn't pop.now that it runs in my shop, i verified the timing is pretty much right on, slightly retarted. there seems to be no corrolation to temp, humidity/moisture from what the seller said. "Maybe after it sits like overnight it has problems but after it starts for just a couple hours you can always start it".

Intermittent problems can be hard to track. You need to test when the problem occurs. Spark--fuel--whatever. I understand, if it breaks down out in the middle of no where, or on the side of a busy street, plus, your by yourself. There's not much you can do. You can still have it checked for trouble codes, now that it runs, see if anything shows up.