F-150 1990 5.0 L check engine code
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F-150 1990 5.0 L check engine code
Hello, and thank you for having me into your forum. As a new member I would like to say to everyone "Hello from sunny Florida!"
I have just purchased this 1990 F-150 truck on Friday and after two days run
out of gas............I was told by the previous owner that this truck has two tanks, but he has never used the second one. So, I have drove until the first tank emptied and when switched to the second one nothing happened, luckily while being at a gas station. Suspecting that the switch between the two tanks does not work, I have filled the first tank-up, but could not start the truck again, also exhausting the battery. I found out with the help of a friend that the timing module went bad and replaced it. The truck started fine but would not stay idling. Also the check engine is on and even after resetting the system by disconnecting the battery for 1-15 min, after few seconds running the engine the check engine light comes back on. Same friend told me that there is a way to de-code the problem when the check engine comes alive. Could anyone help please.
With many anticipated thanks,
cbivolan
I have just purchased this 1990 F-150 truck on Friday and after two days run
out of gas............I was told by the previous owner that this truck has two tanks, but he has never used the second one. So, I have drove until the first tank emptied and when switched to the second one nothing happened, luckily while being at a gas station. Suspecting that the switch between the two tanks does not work, I have filled the first tank-up, but could not start the truck again, also exhausting the battery. I found out with the help of a friend that the timing module went bad and replaced it. The truck started fine but would not stay idling. Also the check engine is on and even after resetting the system by disconnecting the battery for 1-15 min, after few seconds running the engine the check engine light comes back on. Same friend told me that there is a way to de-code the problem when the check engine comes alive. Could anyone help please.
With many anticipated thanks,
cbivolan
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From: Bonita Springs FL
Lead Driver
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an alternate set of instructions, if you need them: http://www.thorssell.net/hbook/eectest.html
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After replacing the ignition module with a new one, my truck still stalls when cold, keeps running a bit rough at about 450-500 RPM/Min after running for five minutes, but at least fixed the “Check engine” light problem. The light does not come on anymore, which tells me the engine is doing better now (or isn’t it?). What really confused me was today when removing the small vacuum hose from the main vacuum tree (right beside the EFI logo) to do some repairs on it, the engine started running beautiful at 750RPM/Min, even when cold. Could anyone help with an answer. Obviously, if I were to drive the truck without the small vacuum hose connected, I would loose some vacuum pressure, and after all it is not normal to run the engine without all the vacuum hoses connected.
Regards,
cbivolan
Regards,
cbivolan
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Joined: Jul 2003
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From: central valley California
Check your EGR to see if it is stuck in the open position... Use a vacuum tester with the truck running as if you just started it put the tester on the vacuum line that goes to the EGR if there is vacuum present the sending unit for the solenoid may be bad causing the EGR to open causing your stall. if your engine does not stall with the EGR vacuum line off then. then the problem lies in the EGR system there should be no vacuum present when frist starting the engine and the engine is cold..
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From: Alabama
Is your ignition module located on the distributor?? When you replaced it did you rotate the dist.? Basically I am asking if you are certain your timing is correct and if you reset it did you disconnect the SPOUT connector when you set the timing??
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Stalling when cold, idles at 500 RPM when warm, works better with a deliberately induced vaccuum leak, all this adds up to me like your IAC (idle air control valve) is plugged up, or the IAC motor is not working, or the wiring to the IAC is bad.
The computer uses the IAC to let a variable amount of air pass around the throttle valve. This lets it kick up the idle speed when cold, and regulate the idle speed at around 650 RPM when warm. It is a feedback process, the computer senses RPM from the PIP signal from the ignition module and opens or closes the IAC to achieve the desired idle RPM. If the IAC is stuck closed, then the "normal" position of the closed throttle blade results in a poor idle at 450 to 500 RPM.
The computer uses the IAC to let a variable amount of air pass around the throttle valve. This lets it kick up the idle speed when cold, and regulate the idle speed at around 650 RPM when warm. It is a feedback process, the computer senses RPM from the PIP signal from the ignition module and opens or closes the IAC to achieve the desired idle RPM. If the IAC is stuck closed, then the "normal" position of the closed throttle blade results in a poor idle at 450 to 500 RPM.
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did you do a basic tuneup yet? plugs, wires, check cap and rotor, change fuel filter(since you ran out of fuel and do not know how old it is anyway) if it has auto drain trans and convertor and change filter.
good luck and welcome!
good luck and welcome!
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From: 3rd Rock
Originally Posted by jpowell2767
I'm having the same idle problem and my mechanic mentioned the same thing you did. How involved is it to verify that it is the IAC? If this is the problem, is the fix to replace the IAC? Thanks.
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Sorry being late with my reply, but had lots of fan troubleshooting and repairing the idle problem. First of all I have found the engine temperature sender to the computer with a broken connector and the engine sounded little better after repairing this problem. Then, the real change was when removed the two large air rubber hoses going from the air filter into the two large air intake flaps (towards the air/gas mixing chamber) and cleaned the flaps and surrounding walls very well with carburetor cleaner using a tooth brush. Now my engine runs perfect! At least has been doing so for the last 100 plus miles.
Good luck you all, and once again thank you very much for your help,
cbivolan
Good luck you all, and once again thank you very much for your help,
cbivolan
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