Won't Start

1987BLazer · May 3, 2004

Hello,

I have a 1987 Chevy Blazer 5.7 EFI. I have replaced the coil and ECI(computer). I have no spark and no gas going into the thottle body. I even checked the grounds on most of the truck I don't know wear they all the grounds are. If any one has any ideas please let me know.

citydriver · May 4, 2004

Welcome to the FORUM

Wish it was under better circumstances....sounds like it could be a bad Ignition module or distributer pick-up coil...the ECM takes the signals from those to trigger the injectors also..you can pick up an injector pulse tester(also known as a noid light) that plugs in2 the injector plug and should flash as you crank the engine...

check the ECM fuse also..no power=no start...get yourself a decent manual (Chiltons or Haynes) they can be very helpful in diagnosing ignition/computer problems.....GOOD LUCK

Butch 02 Denali · May 4, 2004

Can you hear the fuel pump come on when you first turn on the key? If not, I'd check the fuel pump for power first, could just be the fuse.

How was your oil pressure when it was last running? There is an oil pressure sensor that needs to see oil pressure before it will let the engine start. Could be a bad sensor or no oil pressure? I think that sensor on your year is down around the distributor.

Let us know what it turns out to be!

Butch 02 Sierra Denali

1987BLazer · May 4, 2004

I do hear the fuel pump come on when I turn the key. I also checked the oil pressure switch it's on the drive side of the block. I haven't replaced the pick up coil or the ignition module. I have a other pick up coil out of a other blazer I can put on do you feel I should?

Butch 02 Denali · May 4, 2004

Definatly try those, especially since you have them. Another thought is a bad ignition switch.

Butch 02 Sierra Denali

1987BLazer · May 4, 2004

do you mean the key switch? I can take the key out when the truck use to run.

Butch 02 Denali · May 4, 2004

Yup the key switch. Must be pretty well worn out to let the key out. The contacts in the switch part do wear out, and one of them is the "ignition power" signal for the computer and ignition system.

Butch 02 Sierra Denali