HELP 1991 5.0 wont start after filling up at gas station
05-09-2012, 08:09 AM
#22
If the pump keeps priming and the car won't start, you may have an ecm problem. I haven't seen it on these cars but, I have a couple of others and that is what it turned out to be. I assume it could be other things too though.
I would still check to make sure the injectors are working the way I told you since it takes 5 seconds to do. Or you could do it they way they tested it in the arcticle Joel wrote. Either way, they need to be checked.
I assume since the pump was put in the tank was chekced for water. Most of the time that I have seen water get in there, they do crank and sputter before dying out for good. I have seen them towed from gas station parking lots because they wouldn't make it to the road.
I would still check to make sure the injectors are working the way I told you since it takes 5 seconds to do. Or you could do it they way they tested it in the arcticle Joel wrote. Either way, they need to be checked.
I assume since the pump was put in the tank was chekced for water. Most of the time that I have seen water get in there, they do crank and sputter before dying out for good. I have seen them towed from gas station parking lots because they wouldn't make it to the road.
05-12-2012, 12:08 PM
#23
Thread Starter
Join Date: Jul 2008
Posts: 27
Ok, so I checked for fuel pressure at the Schrader valve, fuel did squirt out..but I have no idea w/o a guage to read the actual pressure. I then took off the ICM (ignition control module) from the front of the distributor and took it to auto zone, they tested it and confirmed it failed, so I bought a brand new one and installed it. Still no start. Is it possible that the pickup coil inside the dizzy is also bad?
@TrimDrip... you mentioned earlier "Take something like a metal ended screwdriver and listen to the injectors while the engine is cranking to see if they are clicking." - what exactly will I be doing with the screwdriver?
@TrimDrip... you mentioned earlier "Take something like a metal ended screwdriver and listen to the injectors while the engine is cranking to see if they are clicking." - what exactly will I be doing with the screwdriver?
05-12-2012, 12:41 PM
#24
6th Gear Member
Join Date: Nov 2006
Location: Spfld, MA
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Place one end lightly on the injector, place your ear on the other end of the screwdriver, and cone your hand around the end to "seal" your ear to it, like a sea shell. This will amplify any sound the injectors are making and you'll hear it through the screwdriver like a tuning fork. I find it works better with solid bars, like a long extension for a ratchet, etc.
The pickup inside is responsible for timing the injector firings, so yes to your question.
They're fired via the ground circuit. They should have a constant 12v with the key on, and the ground is cycled to fire them.
The pickup inside is responsible for timing the injector firings, so yes to your question.
They're fired via the ground circuit. They should have a constant 12v with the key on, and the ground is cycled to fire them.
05-12-2012, 01:39 PM
#25
Thread Starter
Join Date: Jul 2008
Posts: 27
I'll try listening to the injectors next. So far, this is what I have found:
fuel pump replaced - turns on with key turned, but never turns off
fuel to rails, confirmed via schrader valve behind alternator - but unsure of exact pressure
spark to wires/plugs when cranking motor
12v to injectors with key turned on
ICM (ignition control module) test failed at autozone, so it's been replaced
should I now proceed to pickup coil inside dizzy if injectors pass sound test?
fuel pump replaced - turns on with key turned, but never turns off
fuel to rails, confirmed via schrader valve behind alternator - but unsure of exact pressure
spark to wires/plugs when cranking motor
12v to injectors with key turned on
ICM (ignition control module) test failed at autozone, so it's been replaced
should I now proceed to pickup coil inside dizzy if injectors pass sound test?
05-12-2012, 01:42 PM
#26
Thread Starter
Join Date: Jul 2008
Posts: 27
@TrimDrip...you posted
"If the pump keeps priming and the car won't start, you may have an ecm problem. I haven't seen it on these cars but, I have a couple of others and that is what it turned out to be. I assume it could be other things too though."
ECM? Electronic Control Module? Whatever its called, where is it located?
"If the pump keeps priming and the car won't start, you may have an ecm problem. I haven't seen it on these cars but, I have a couple of others and that is what it turned out to be. I assume it could be other things too though."
ECM? Electronic Control Module? Whatever its called, where is it located?
05-12-2012, 02:34 PM
#27
That is the computer. It is located in the passenger side kick panel.
Its kinda funny that the old module tested bad and didn't fix the car....I would take it back and get another one.
I have never seen it done before off the car besides taking the cover off and looking at it for signs of being hot.....Kinda makes me thing someone put a multi-meter on it or something and did it wrong or looked up the wrong specs.
Its kinda funny that the old module tested bad and didn't fix the car....I would take it back and get another one.
I have never seen it done before off the car besides taking the cover off and looking at it for signs of being hot.....Kinda makes me thing someone put a multi-meter on it or something and did it wrong or looked up the wrong specs.
05-14-2012, 11:30 AM
#28
Thread Starter
Join Date: Jul 2008
Posts: 27
I tried listening to the injectors, couldnt say if they were working or not, too much noise for me while engine is cranking and I'm not sure exactly what Im listening for. I tried listening with a ratchet extension and also with a hollow metal pipe.
Is it worth my while to replace the pickup inside the dizzy? If I do and still no success, would assume its my ECM. Is there any way to test the ECM or do I have to fork over $ for a new one not even knowing if it's the ECM or not.
As far as the ICM, I took my original one to AutoZone and they have a machine that tests modules, has all kinds of connectors. It said mine was bad so I replaced it.
Is it worth my while to replace the pickup inside the dizzy? If I do and still no success, would assume its my ECM. Is there any way to test the ECM or do I have to fork over $ for a new one not even knowing if it's the ECM or not.
As far as the ICM, I took my original one to AutoZone and they have a machine that tests modules, has all kinds of connectors. It said mine was bad so I replaced it.
05-14-2012, 03:12 PM
#29
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Join Date: Nov 2006
Location: Spfld, MA
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The pickup is likely the culprit, so yes I'd say it's worth your while. It's $15, and with a decent toolset you can be done in an hour or so. However, you could rent some noid lights from Autozone and verify the injectors aren't firing first.
05-14-2012, 07:02 PM
#30
Thread Starter
Join Date: Jul 2008
Posts: 27
ok, so I couldnt tell if the injectors were pulsing or not so I had it towed to a local repair shop for an $85 diagnosis. He confirmed there was fuel pressure (I believe he said 40lbs) and there was in fact spark which I already knew. He then used the noid set to test the injectors, they were NOT pulsing. Next, he is going to test/check the pickup coil. If it's the coil, he quoted me around $215 which includes the $85 diagnosis charge. ($85 + $40 (parts) and 1hr labor @ $85).