Car will not start

[willto]

My 97 TC won't start right now. I used the car this morning, droved for around 10 miles, and everything was fine. But when I tried to start the car at noon, it stops working. The starter cranks normally, but the engine does not start. I've swaped relays under the hood, it didn't help. Checked fuel pump switch in the trunk, it's good. The battery is new, the starter was replaced last winter. I got the same situation a month ago. At that time, I towed the car to the dealership for a check. The car started normally at the dealership. They started the car at the first try. They checked the starting system, fuel system and no problem was found. The car worked fine since then, but the problem came back again. I don't have a clue what's going on.

[Dereck]

Hi Willto

There are a hundred things it could be from fuel pump not pumping to the crank angle sensor faulty.

First two simple checks are:

1, Look for fuel pressure by pushing the valve in the the fuel rail near cylinder 4 injector (or hook up a gauge).

2, Check for a spark by pulling a plug wire fitting an old plug and cranking the engine.

You could also hook up a diagnostic tool to the DLC and check for fault codes/sensor values

Regards

Dereck

[willto]

Hi Dereck,

Thanks for the prompt reply. Those are simple ways to check fuel pressure and spark. I did the first check, uncapped a metal valve close to the innermost fuel injector at the passenger side, used a small allen key to push the stem in the valve and the gas spouted out. Does that mean the fuel pressure is fine? I'll check the sparks later since I don't have an old spark plug at hand.

Regards,
Willto

[willto]

Just got back from work, got a new spark plug from autozone. When I was ready to test the sparks, the car started normally!!! That was the first try after sitting for 5 hours. What could be wrong with it?

[no0c]

A 1/4" X 2-1/2" bolt would do the same thing or a phillips screwdriver, etc. Stick it in the wire connector, crank the engine and see if a spark will jump from the bolt to ground.

Alternatively you could pull a wire from the coil and while cranking move it back toward the coil and observe if a spark happens. An insulated pliers in either case might be a good idea unless you are up for a cheap thrill.

Good luck.

[ABE]

A failing crankshaft position sensor can cause intermittant starting problems. But lots of other sources too.

Good luck.

[Chevyguy]

Since you had fuel pressure, the crank trigger sensor is the next likely problem.

If you had a 91-95 I would suspect the EDIS-8 module. The chance of a PCM fault is pretty low. Does the check engine light come on when you turn the key to the ON position? I did have a GM car which had similar symptoms to yours. It was embarrasing when I waited 2 hours for a tow and the car started when the guy arrived. I finally noticed that the check engine light did NOT come on when the car would not start. In that case replacing the PCM DID indeed fix the problem.

[Matthew]

Another vote for CPS gone intermittently bad, or the connector to said sensor is corroded.

[no0c]

As many have suggested, I would remove the CPS harness connector. Clean with contact cleaner and apply dielectric grease to both the harness plug and pins on the CPS and reinstall the connector.

The CPS is located just above the air conditioner compressor, passenger side, front corner of cylinder block.

Good luck.

[willto]

Your guys are amazing! It is the problem of connection to CPS. This morning, my TC cranked over but would not start again. I wiggled the cable to the CPS, the car started right up! Thanks all for your expertise comments, I'll clean the connection and put some dielectric grease to it.

[zardiw]

Since I have to pull my fuse to shut off my TC nowadays, I've noticed that sometimes when I put it back in the car won't start.....so I pull it out and push it in again, and everything is hunky dory..........z