gregmy123

Hi Everyone,

Hope you guys can help me with this.

1987 Chevy IROC Z28/5.7L/ TPI/VIN 8/AT - Nearly 160,000 Miles/ Fuel Pump is fairly new according to last owner - no receipt.

Can't figure out why she won't start. Only cranks over. Here is list of what I have replaced and the tests I have done.

Replaced:

fuel filter
Spark Plugs
Distributor Cap
Rotor
External Ignition Coil
ICM/with thermal compound ( Cheap one ordered off Ebay)

I have no "Service Engine Soon" light when I turn key to On. Bulb is good.
Fuses in fuse box under drivers side dashboard all check out as good.
The 20 amp fuse mounted on passengers side engine compartment by battery is good.

Tests I have done:
I connected spark plug tester to all spark plugs and spark plug wires (which are fairly new), and cranked engine and got flashing light at each.
pick Up coil tested OK with multi-meter.
I connected 12 V to G terminal on AlDL to test fuel pump- fuel pump turns on.
Removed fuel feed line at engine fuel rail and again connected 12 V to G terminal of ALDL and fuel pump pumped out a pint in 5 seconds.
Connected fuel pressure tester to fuel rail and turned key to on and get no pressure reading.

Hope you guys can give me some guidance!

Thank You!

Greg

CapsFan

Hi Greg,

I have a 1990 IROC thats doing the same thing. I didn't do much to it yet, checked the fuse for the fuel pump, the relay is working & I changed fuel pump. I put it on a scanner & it's not throwing any codes. I'm an old school car guy so I think I'll be taking mine into the shop & let them fix it. I have a thread started about my not starting problem, you might want to do a search for it. I'll be posting what fixed it as soon as I find out. Good luck!

gregmy123

Hi CapsFan,

OK, I will check out your thread!

I'm about ready to bring to shop also. What I don't quite understand is why my fuel pump does not prime for 2 seconds when I turn the key to "on" and therefore does not pressurize the fuel rail as I get zero pressure on my fuel pressure tester at fitting. I am going to replace fuel pump relay to see if that helps.
I see that some folks mention OP switch or sender as being back up for fuel pump circuit if relay fails. But you need to crank engine longer to get oil pressure up to close circuit. I may replace this also. WTF.

Thanks!

CapsFan

Decided today to have a new ignition key made. After a little research, I found that a bad ignition key (resistance for VATS) may cause the car to crank but not start. I need another set of keys anyway. I'll check the resistance on the key and have a new one made, see what happens then.

See ya.

Tyanez74

Hi Greg,

mine is doing the same. Did you figure out the issue? If so, I may do the same.

thanks!