How do I test my engine computer/
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How do I test my engine computer/
I have a 1989 F150 with a 351W and it won't start. If I spray starter fluid it will fire. There is fuel pressure at the fuel rail but nothing getting to the cylinders. Someone told me it was probably a bad computer. Before I go and buy a $100.00 part I'd like to know that it is really bad. Anyt advice or suggestions?
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From: The dark carnival
The only way that I know of to do this is to try it out in another identical truck or try a known good one in your truck. Either way would tell you the status of your own computor.
Companies like Standard Motor Products have a machine that plugs into the EEC-IV computor and simulates all the inputs and outputs and this machine displays everything that the computor "sees" and "does." Hooking up to something like this would test the computor but as far as I know not too many people have access to something like this and even if I wanted something like this I wouldent know where to buy one...
Companies like Standard Motor Products have a machine that plugs into the EEC-IV computor and simulates all the inputs and outputs and this machine displays everything that the computor "sees" and "does." Hooking up to something like this would test the computor but as far as I know not too many people have access to something like this and even if I wanted something like this I wouldent know where to buy one...
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From: Easton,Ks
Originally Posted by ChurchBuilder
I have a 1989 F150 with a 351W and it won't start. If I spray starter fluid it will fire. There is fuel pressure at the fuel rail but nothing getting to the cylinders. Someone told me it was probably a bad computer. Before I go and buy a $100.00 part I'd like to know that it is really bad. Anyt advice or suggestions?
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I found the black and white wire. It seems to be fine. I have no power to the fuel injectors. Does this mean a bad computor/ECU? If so where is i=t and what does it look like? Is there another part that might cause this?
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From: Easton,Ks
Originally Posted by ChurchBuilder
I found the black and white wire. It seems to be fine. I have no power to the fuel injectors. Does this mean a bad computor/ECU? If so where is i=t and what does it look like? Is there another part that might cause this?
It could also be a bad wire or plug and the ECU is not getting the message that the plugs are firing.
Go here to see what it looks like:
http://fordfuelinjection.com/?p=2
Last edited by subford; Oct 7, 2006 at 06:50 PM.
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The pump is working, I also drained the gas out in case it was bad. I can't even find the ECU so it's hard to trace the wires. I did find a black plastic bow with wires going to it but not as many wires as I would expect for a computer. 13 or 14 wires is all and no black ground wire.
Does anyone know where the ECU is?
Does anyone know where the ECU is?
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From: Easton,Ks
Originally Posted by ChurchBuilder
The pump is working, I also drained the gas out in case it was bad. I can't even find the ECU so it's hard to trace the wires. I did find a black plastic bow with wires going to it but not as many wires as I would expect for a computer. 13 or 14 wires is all and no black ground wire.
Does anyone know where the ECU is?
Does anyone know where the ECU is?
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Yes, thanks for finding that. I am studying it but not sure how to read it very well. The pump, tank selector and ignition all seem to be working. The pressure seems fine and I can heqar the gas pump go on. I disconnected the fuel filter and gas shoots out and the pump pushes fuel out. I didn't measure the pressure myself but the last guy said it was 40lbs. It just seems as though the injectors aren't allowing fuel into the cylinders. The spark plugs smell like starting fluid but not fuel.
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From: Bend,OR
pull codes, that website fordfuelinjection.com has all kinds of info and explains the process for getting the codes. has it ran and when? has it been sitting for awhile give alittle history here to bring us up to speed.
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Haven't tried anything for a couple of days. That web site looks great. Thanks.
The truck was opwned by a guy who got into a motorcycle accident. It sat for a long time (6 mo) then he decided to get a new truck. He backed it into his driveway and it sat for 9 months. Then he gave it to my daughter. Her husband and I worked on it and never got it started. I sat again for 6 months and now I'm determined to get it going within the next 2 weeks. There is pressure at the fuel rail. The gas smells bad so I drained the tank and put in new gas. I tested the injectors with a noid light and there is no power. The pump kicks on but keeps running with the key on. The truck will fire and sounds good with starting fluid but as far as I can tell there is no fuel getting to any spark plugs.
When I tried to do a self test It didn't work but I'm not sure I was doing it right. I just got a steady 12 volts. I'
ll look on the web to gert better directions than the Haynes manual.
The truck was opwned by a guy who got into a motorcycle accident. It sat for a long time (6 mo) then he decided to get a new truck. He backed it into his driveway and it sat for 9 months. Then he gave it to my daughter. Her husband and I worked on it and never got it started. I sat again for 6 months and now I'm determined to get it going within the next 2 weeks. There is pressure at the fuel rail. The gas smells bad so I drained the tank and put in new gas. I tested the injectors with a noid light and there is no power. The pump kicks on but keeps running with the key on. The truck will fire and sounds good with starting fluid but as far as I can tell there is no fuel getting to any spark plugs.
When I tried to do a self test It didn't work but I'm not sure I was doing it right. I just got a steady 12 volts. I'
ll look on the web to gert better directions than the Haynes manual.
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From: Easton,Ks
Originally Posted by ChurchBuilder
Haven't tried anything for a couple of days. That web site looks great. Thanks.
The truck was opwned by a guy who got into a motorcycle accident. It sat for a long time (6 mo) then he decided to get a new truck. He backed it into his driveway and it sat for 9 months. Then he gave it to my daughter. Her husband and I worked on it and never got it started. I sat again for 6 months and now I'm determined to get it going within the next 2 weeks. There is pressure at the fuel rail. The gas smells bad so I drained the tank and put in new gas. I tested the injectors with a noid light and there is no power. The pump kicks on but keeps running with the key on. The truck will fire and sounds good with starting fluid but as far as I can tell there is no fuel getting to any spark plugs.
When I tried to do a self test It didn't work but I'm not sure I was doing it right. I just got a steady 12 volts. I'
ll look on the web to gert better directions than the Haynes manual.
The truck was opwned by a guy who got into a motorcycle accident. It sat for a long time (6 mo) then he decided to get a new truck. He backed it into his driveway and it sat for 9 months. Then he gave it to my daughter. Her husband and I worked on it and never got it started. I sat again for 6 months and now I'm determined to get it going within the next 2 weeks. There is pressure at the fuel rail. The gas smells bad so I drained the tank and put in new gas. I tested the injectors with a noid light and there is no power. The pump kicks on but keeps running with the key on. The truck will fire and sounds good with starting fluid but as far as I can tell there is no fuel getting to any spark plugs.
When I tried to do a self test It didn't work but I'm not sure I was doing it right. I just got a steady 12 volts. I'
ll look on the web to gert better directions than the Haynes manual.
Note that the spark plugs will fire while cranking without the computer working.