Mechanics

CHEVY WHY WONT IT START

1997 Chevrolet Blazer

Engine Performance problem
1997 Chevy Blazer 6 cyl Four Wheel Drive Automatic 153000 miles

Ok this has got me stumped my 97 blazer just shut down its been running fine since I bought it but then without warning it just shut down while I was driving.
all the electrical components seem to be functioning when I turn the key it acts like it is about to start but never fires up. Is this a fule problem? A computer problem? Or something completly different?
Avatar
BlazerDrew
September 18, 2009.




It's easiest to check for either a spark or fuel pressure first. To check for fuel pressure, connect a pressure gauge to the fuel pressure releif valve. It is located in front of the distributor, usually has a black, plastic screw-on cap on it; once the cap is removed (by hand) it reveils a " stem" which resembles a valve stem on a tire. Attach the pressure gauge here. Pressure should be around 50- 60 psi if the pump is working properly. Much lower than that (say 20 -35 psi) the engine might start and then stall or just act as if it is going to start. Even if low pressure is confirmed check the fuel filter before condemming the fuel pump.
To check for a spark remove a spark plug wire from a spark plug and place it about 1/4" to 1/2" from ground (usually a nut or bolt) spin the engine over as if you are trying to start it. Look for a spark. If one is present replace the spark plug wire onto the spark plug and check another wire the same as you did the first. If you get a spark there also, then the problem is most likely not the ignition system. If you don't get a spark at either, check to make sure that the distributor is getting battery voltage with the key on. If it gets battery voltage but still no spark, you'll have to test the crank sensors, Ignition control module (ICM), wiring from ICM to PCM, etc. If that's the case I can get that info to you. Let me know how this works. If necessary I'll try to give you more information.

Freemba
Sep 18, 2009.


AD