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Tech / General EngineIs your car making a strange sound or won't start? Thinking of adding power with a new combination? Need other technical information or engine specific advice? Don't see another board for your problem? Post it here!
So I've been working on my 89 IROC-Z restoration, and the car is almost finished. Anyways, when I bought the car, it had been sitting since 2008. I had the fuel pump and filter replaced at that time, and got the car running. It has been running flawlessly ever since, but it has only had 220 miles put on it since the fuel pump was replaced in December. Anyways, tonight, I installed the panels under the dash on each side, installed my door seals and rebuilt my hatch pull down assembly. I moved the car outside the shop, and shut it off to go lock up the body shop. Walked back out to the car, and it cranks and cranks and doesn't even attempt to start. There is ZERO fuel at the shrader valve in the fuel rail. Thinking that maybe, just maybe the gas gauge isn't accurate and it might just be out of gas, I put 4 gallons of fuel in it out of a gas can. Still nothing.
Did my new AC DELCO fuel pump crap out on me already after only 200 miles? Also, I checked all the fuses in the fuse box with a test light and everything is good.
Could it be a VATS problem? I have no idea if they even crank over if something crapped out in that department. I also tried my spare ignition key and nothing changed
I have some spare relays and swapped them around at the firewall by the brake booster. I'm not exactly sure which relay is for the fuel pump, or if my spares are even any good...because nothing changed.
Could my fuel filter be plugged already? After all, the car was sitting for years...but I would think that at least SOME fuel would make it to the fuel rail.
I can't hear the pump run when I cycle the key...
Could I have moved something when I installed the under dash panels? It DID run after that....only moved around the block.
I'm thinking about maybe starting with replacing the filter again. And buy a NEW relay. Hell I don't know what to do. I'm super bummed.
First and foremost, VATS will not kill the fuel pump, VATS is in control of inhibiting the starter and fuel injector pulse only.
You said you checked the fuses under the dash, did you also check the fuse ("Inline fuse 2" in the diagram) under the hood mounted on the right hand fender? That fuse does protect the fuel pump (as well as the ECM).
You should take a voltmeter(or 12V automotive test light) to the fuel pump relay and check for power there, you say you can't hear the pump run, it's not likely that the fuel filter would cause the pump to be dead, in fact a clogged filter would have the pump trying extra hard to push fuel and might even make it sound louder rather than making no sound at all. Start by checking the orange wire on the fuel pump relay to see if you've got +12V there, if so the next check will be the dark green/white wire while your assistant turns the key from off to on (not start, just on) to see if you get power for about 2 seconds (you should also be able to feel the relay make a slight click when the key is turned on).
Hopefully this gives you a good starting point for your troubleshooting.....
Last edited by OrangeBird; Apr 10, 2021 at 06:15 AM.
Fuses don't blow by themselves - check your wiring for damage, corrosion etc or pinched during pump install. Pump drawing too much amperage could blow the fuse as well
Fuses don't blow by themselves - check your wiring for damage, corrosion etc or pinched during pump install. Pump drawing too much amperage could blow the fuse as well
I definitely need to find the root of the problem. That fuse has blown 2 more times.
A bad ecm will cause the fans to run when the key is turned on.
try unplugging the ecm and see if the fuse blows. A high pump amp draw will also cause the fuse to blow.
A bad ecm will cause the fans to run when the key is turned on.
try unplugging the ecm and see if the fuse blows. A high pump amp draw will also cause the fuse to blow.
Thank you! I'll give that a try. The car came with totes full of parts, and there is an ECM in there, but I don't know if it's for a 5.7 TPI car or not. I'd have to try to look up the part number
That’s a 1226455 1984 l69 automatic not the same ecm.
Thank you!!
So can I just install an aftermarket chip? Like Hypertech, etc? Or did you mean the entire ECM need to be changed with my current chip swapped over to the new ECM?
So a buddy of mine had the 1227165 ECM on a shelf. Swapped it out and swapped the chips, too, so I still had my same chip. So far I haven't blown that fuse again. I think I'm actually good. BUT, one cooling fan still comes on when I turn the key to the on position
So a buddy of mine had the 1227165 ECM on a shelf. Swapped it out and swapped the chips, too, so I still had my same chip. So far I haven't blown that fuse again. I think I'm actually good. BUT, one cooling fan still comes on when I turn the key to the on position
maybe a previous owner put a jumper in the fan relay by chance? I would open it up and make sure its not modified
So a buddy of mine had the 1227165 ECM on a shelf. Swapped it out and swapped the chips, too, so I still had my same chip. So far I haven't blown that fuse again. I think I'm actually good. BUT, one cooling fan still comes on when I turn the key to the on position
Which fan comes on with the key, passenger or driver? Drivers side is controlled by one of the relays on the firewall which the ECM activates. The passenger side fan is controlled by a temp switch in the cylinder head.
On mine when I bought the car, the green/white wire from the relay was cut and grounded. The wire from the temp switch was removed and grounded also. This caused both fans to come on with the key. Check these circuits and hopefully you can find where the PO permanently grounded each circuit.
It's the passenger side fan that comes on. And, it's still blowing that fuse. I'm going to dig into it more over the weekend if it doesn't rain so I can get my car to the body shop where almost all of my tools are.
do you have a picture of where this fuse is located?
I can get a picture later on. It's a regular 20amp spade fuse just like what's in the fuse box under the driver's side of the dash. It's in a little plug in with 2 wires on it, right in the wiring by the battery.
It's the passenger side fan that comes on. And, it's still blowing that fuse. I'm going to dig into it more over the weekend if it doesn't rain so I can get my car to the body shop where almost all of my tools are.
Hi dagwood, I hope your short circuit isn't buried too deep, sometimes they can be a real pain to find. I figured I'd post a couple of pics here for bigdavesiroc and any future readers who may find this in a search.
Pictures of the underhood fuse, note that there is supposed to be a plastic retaining tab that is broken ;
check fan motor for high draw. unplug constant-on fan and see if the fuse blows. also check the relay for the constant-on fan. can swap fan motors around for testing purposes. constant-on fan relay sounds 'stuck.'
Last edited by MrPackstin; May 9, 2021 at 09:41 PM.
Hi dagwood, I hope your short circuit isn't buried too deep, sometimes they can be a real pain to find. I figured I'd post a couple of pics here for bigdavesiroc and any future readers who may find this in a search.
Pictures of the underhood fuse, note that there is supposed to be a plastic retaining tab that is broken ;
Thanks......I think we took that out of the system when we switched to a carb. But I'll look and see if I can't find it. I really appreciate it.