I have a 89 IROC with a 350 TPI. About a month ago, I was driving it down the road when suddenly, the car turned off. I attempted to restart the car, and it would, but as soon as I would shift it into drive, it would turn off. Finally, it didn't start anymore. I decided that the fuel pump was not running and I replaced it. I also decided to order a new exhaust system because I had to cut the old one to get to the fuel pump. I started up the car after replacing the fuel pump, and, for a moment it turned on, then off. Now, no lights go on when I put the key into the ignition. No check engine light, no sounds, no anything-- as if the electricity was not running through the car. The battery is charged. 12 volts. The positive wire had electricity running through it. The battery was disconnected for a month while I was repairing it. Someone told me I had to reset the car by pulling something out and then putting it back in (under the hood).

 

What your friend was probably mentioning, is to reset the car's computer.....you can do so by disconnecting the fuse marked "ECM" or simply disconnecting the battery..........wait 30 seconds or more before hooking it back up........if you're on the extra-careful side, go have lunch or something before you hook it back up. BUT..... this isn't going to help you anyway. You might want to reset the ECM after making major performance modifications, or after a tune-up.....but that's not your problem if the car won't start.

Firstly, GM side-mount battery bolts come loose surprisinly often; check and re-tighten them with a 5/16" or 8mm wrench....there's also a spot on the bolt where you tighten it with pliers if need be in an emergency.

Observe your car's volt meter when you turn on the key; it should be at around 11 volts or greater..... in any event, it can never hurt to hook up a jump-start from another car...your battery might just be weak from sitting.

Also, on most cars, there's more than just one wire attached to the battery; wiggle and pull on them and make sure none have come loose, or broken on the inside.

As you will see, the battery's ground cable goes both to the fender and to the engine block; follow the wire along its path and check for any obvious breaks. The positive cable goes down to the starter; you may have to jack up the car to check it fully. If you suspect one of the wires is bad, you can use a jumper cable to duplicate its function, then attempt to start the car.

There are some fusible links in the car; I'm not sure if theyr'e near the battery or at the starter....but the next step would be to get a test light or meter and verify that they're good.

 

The battery tests at 12 volts. I tried to jump start the IROC with a V6 mustang, but no luck. The car was without a battery for about a month, so for sure the computer was reset. I will check tomorrow if the volts are running to the starter. Thanks for the advice. I'd check right now, but it's been raining pretty hard in the evening.

 

It may be the alternator. Turn to the car to run, then take a voltmeter to the pos. lead (should only be one wire) to the alternator, and find a suitable ground(the alternator itself or the bracket should work, test the ground first by putting the pos wire to the batt and using the ground), if it is not getting any volts, it may be a bad ground(check the bolts of the alternator) or the circuitry. However, if it is getting volts it mauy be the alternator itself

 

Sorry, i did not mean the alternator at all. I meant to tell you to check the starter motor. You have to put it in run, not accessory. And you may also want to check the ground for both the battery and the starter motor
Sorry
David Leo

 

Hi, thank you all for the replies! I traced the wiring and I was able to reset the computer. Right after, I ran a check and got only code 12, which meant that everything was ok. I was able to start the car, and I could hear the fuel pump kick in. Later on, though, it seemed like the new fuel pump gave in: the pump seems to turn on and off randomly. The volts to the fuel pump are inconsistant. Is this because of a faulty fuel pump relay? Or a bad computer? Sorry about all of the questions, you guys are a great help to me and I appreciate anything you can offer!

Mick

 

You may want to check the voltage at the relay from the ECM side. It could be a dieing relay or maybe the oil press switch (above the oil filter) going bad. Could just e some loose wiring too..

This may help you in you hunting quest...



Oh yea, if you put +12v to the G terminal you can test the pump itself.