My truck died the other day, and I can't get it to fire.

I filled the gas tank all the way up (which probably hasn't been done in years)
I changed the oil
After driving for a while, I could hear the truck sounding like it was starving for gas (losing power, then reving up).

When it died I thought it was probably the fuel pump or the fuel filter getting plugged from gunk from the tank.

After further review I decided it's a spark issue. To test it, I shot carb cleaner into the air intake and turned it over, and it didn't fire.

It turns over fine, so I decided to change the Ignition Control Module, since it should be done anyway. I still have no spark (confirmed with the carb cleaner test).

Now I'm trying to decide what to try next, do I change the coil, or can I test it? Can I test the computer? Any ideas?

 

Unplug the computer.
See if spark then returns while the computer is unplugged.
If not see if you have power on both small wires at the Ignition Coil.
If not check for a bad plug on the Ignition Coil.
If you have power on the two small wires you could have a bad PIP sensor.
But make sure you are not getting spark with a spark tester.

 

Hey, is it giving a check engine light? if so, hook a scanner up and drive it. write down all your codes. Unplug the scanner, reconnect it, and do it again. If you have different codes than before, it's a PCM reset problem. That can mean a bad PCM. that's all I can think of.

 

Hey, is it giving a check engine light? if so, hook a scanner up and drive it. write down all your codes. Unplug the scanner, reconnect it, and do it again. If you have different codes than before, it's a PCM reset problem. That can mean a bad PCM. that's all I can think of.

 

I put it on the charger last night and will check the stuff out listed above. The truck doesn't start so I can't use a scanner when I drive it.

I'll pull the computer and see how that goes, and I should be able to test the coil as well. It just seemed weird that it took so long to die if it was a spark issue instead of dying immediately.

 

You can't get it on fire? Try gasoline and some old sheets. That's how I always started the bon fires when I was working as a "landkeeper". Just be careful!

Oh, you meant "no fire" as in plugs? Oops.

 

AH, well, even then. Connect the scanner then disconnect it. disconnect the battery and reconnect it. if the codes are different, PCM. thats what this oldsmobile at my school did anyways. It's easier to tell if you could drive it though. Try to get a ground strap when removig the PCM so no static hurts it. Also, if it is the PCM, find what caused it to go bad.

 

Well I'm still at it. The coil is good, there is spark in the plugs, and it's getting fuel to the EFI unit. The problem I found now is that there is no power at the injectors. I took a plug out and it was dry as well.

Now the battery gets hot when I turn it over. I'm starting to think maybe there is a wire broken or burnt inside the motor compartment somewhere. The only things left that I can think of is a bad brain box or bad wiring somewhere.

How hard is it to replace the wiring? It looks like there are about 50 wires comming out of the harness, so I'm worried about having to redo that.

 

If you do not have power on the red wire at the injector then it sounds like your EEC Power Relay is not being picked when you turn on the key. Check the wiring under the socket for the EEC Power Relay.
Have someone turn on the key while you hold your hand on the EEC Power Relay and see if it clicks. If it does not click and the wiring under it is good then change out the relay. If it still does not click after you change it then you may have a bad Ignition Switch on top of the column down by the floor board.
Does the radio play when you turn on the key?
Heater blower?

 

Thanks Bill,

I actually changed the EEC Relay last week. When I was messing with it, I could hear a pump type noise comming from the injector area. Now all of a sudden it's having a hard time turning over, and the battery gets hot when I try to turn it over.

First I wonder if the starter didn't go out from trying to turn over so many times. Then I wonder if I have a short some where. I'll probably change the ignition switch either way since it's only a $10 part.

 

It sounds like you have a couple problems. If your battery is getting hot and it's slow to crank then you might have a bad ground or bad battery cables. They break down internally and cause starting problems like that.

If you have access to a fuel pressure gauge, check the fuel pressure. That will at least rule that out as a cause.

You can buy or rent a noid light to see if the injectors are firing.

You can also use a spark tester to see if you're getting spark. Spraying carb cleaner into the intake isn't a very good test.

I would also pull the codes. Either use a paperclip and these directions: http://broncodata.com/tech/codes.htm or buy a code reader. I have an Innova 3145 and it makes pulling codes so much easier.

 

OK, so I'm back at it again. I borrowed a really nice digital code reader and tested the truck. It came back saying "11 system pass" which means it didn't find any codes.

We did all the tests, and don't show any power to the injectors. I have changed the EEC Power Relay, and am starting to think it almost has to be the computer or the wiring. Is there a way to test the computer?

I may have killed my starter now too by trying to turn it over so many times. I'll replace that, which should be done anyway since this one is so old. I just don't want to spring $150 for a computer if that's not the problem.

 

I doubt it's the computer if you're getting codes from it. If you're not getting any power to the injectors then you either have a wiring problem between the EEC and the injectors or the computer isn't seeing that the engine is turning over via the pip module (aka hall effect sensor) in the distributor. I have seen more than one of these go bad.

 

So,

I'll check the wiring tonight. I tried calling my auto parts store and they had no idea what I was talking about. I asked for the PIP sensor and had them try "Hall Effect Sensor". I did some research online after your post, and this looks like it could be the culprit.

Any idea how I can get the right part? Should I be wording my request differently?

 

It's easier just to buy a whole new distributor. Unless you're on a really tight budget or have a lot of time on your hands and want to tear it down and rebuild it, a new one is the way to go.