Ford 460 diagnostics problem

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Aug 18, 2006 | 09:55 PM

#16

tebreuer

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Some one suggested I change the idle air control, and I did that. It may idle marginally smoother, but it still dies lot. I think the Ford people told me the PCM is obsolete and can only be rebuilt, no replacement is available??? That doesn't make sense to me, but do you know a good place to get one?

Aug 19, 2006 | 07:53 AM

#17

subford

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Joined: Aug 2005

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From: Easton,Ks

Quote:

Originally Posted by tebreuer

You might want to try changing the TPS and the ECT (the one with two wires) sensors as they will cause your kind of problem without a trouble code and of course the EGR valve stuck open will cause it also.

I am guessing you have a C6 Transmission with no Computer control of the transmission. As far as the PCM (I think you have the EEC) I have heard this about Ford and Auto Part stores that you have to send it out for repair.

Getting a used one for you RV may be a little hard to find, the only place I can think of is a large RV salvage yard down around Joplin Missouri. They do ship.

If the PCM is bad and has not smoked you may be able to get it fixed at Electronic Repair Shop as when they are repaired them all they do to them is replace the Capacitors and the output switching (grounding) devices or the voltage regulator if they are bad.

If you want replace it you need the program code off the PCM and not the part number. This code is near the plug on the PCM as in the diagrams below. Make sure the one you get has the same program code the ones in the diagrams below is AL9 and HUG2.

http://i54.photobucket.com/albums/g9...ransistors.jpg

http://i54.photobucket.com/albums/g9...rogramCode.gif

Aug 20, 2006 | 10:23 AM

#18

EPNCSU2006

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Joined: Nov 2002

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From: Concord, NC

Do codes 126 334 or 539 make any better sense? My dad's 92 truck has three digit codes, so I would not be surprised if this used the three digit codes too. I would not suggest just throwing parts at it. You'll just spend a lot more money than is necessary and you'll most likely end up replacing a bunch of perfectly functioning parts.

Aug 20, 2006 | 11:24 AM

#19

subford

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From: Easton,Ks

126 = MAP/BARO out of range - Maybe unplugged?
334 = EGR Valve not fully closed - Clean or replace.
539 = Maybe the A/C switch was on when you ran the test.

Aug 20, 2006 | 10:05 PM

#20

tebreuer

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I am hopeful this is starting to make sense-I will check the MAP sensor and try cleaning the EGR tomorrow. Any advice on how best to clean it, or is it best just to order a replacemant? The best price I find is about $125, and the MAP sensor is about $100-I hope it is unplugged. It ran worse after I got it back from Ford, so perhaps they unplugged it and didn't hook it back up. I have found several things left loose or unhooked already.

Aug 20, 2006 | 10:10 PM

#21

tebreuer

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By the way, I am certain the A/C switch was on.

Aug 21, 2006 | 11:16 PM

#22

tebreuer

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I want to post a final message of thanks for the help. The MAP, when I found it, was unplugged. The EGR valve was stuck open. I cleaned it, plugged in the MAP, and it idles smooth as silk and runs well too. Thanks very much to all of you for your suggestions and help. The last two posts by EPNCSU2006 and Subford were great!!!