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thunder47for · 08-02-2013, 01:09 PM

I just Bought a low milliage 1990 Bounder with a 460 ford 7.5 that some one cut the diagnostic port off and it has a trouble code ,so I went to the junk yard and picked up a ford obd 1 port but have no idea where to put the wires back in went down to the local garage and they got on line no drawing of the order of the wires or color code checked at the junk yard and 460 pickups diffirent colors so it looks like I will have to find some one with a 1990 bounder with a 460 ford in it that would make a simple drawing of that connector for me and e-mail it to me this has me scraching my head (lol)

stink · 08-02-2013, 01:15 PM

If you have anti lock brakes it's test connecter will be identical to the PCM diag port. It's very easy to confuse the two. I do not know where the test connecters are located on your coach. Might check the wiring color codes for the abs connecter and see if they match your wires.

thunder47for · 08-02-2013, 01:36 PM

Someone just took some side cutters and cut them off I got the Ford dia. Port but just don't know what color wires go where a person with a 1990 bounder with a 460 in it would be a wish come true where I could get a drawing of where the wires go

Stan.Birch · 08-02-2013, 01:39 PM

It's called an EEC-IV Self Test Input (STI) Connector. Lots of pictures in Google Images under that designation.

EEC IV Self Test hookup

1983 Ford Bronco Diagrams picture | SuperMotors.net

thunder47for · 08-04-2013, 05:04 AM

Well with the help of everybody I got wiring straightened out and now I'am getting a 172 code a o2 lean code this motor home sat a lot and I changed the o2 sensor and coolant sensor and still got the same code I'am thinking it could be as simple as a clogged fuel filter and putting in some injector cleaner what your thoughts ???

mpaton · 08-04-2013, 07:46 AM

I'd be very surprised if you had a 3 digit error code on a 1990. Presumably you were counting light flashes. Try it again, assuming you're getting 2 digit codes, or you could get an Equus 3145 for about $25 which will display the codes for you. Of course it could be that someone changed the ECU as well as cut the wires off. Can you post the code from the side of the 60 pin ECU connector. It's the digits in the much bigger font size than all the other lettering.

thunder47for · 08-04-2013, 11:02 AM

I got a Equis code reader and did it twice and it comes up a 172 code o2 lean

subford · 08-04-2013, 11:34 AM

Yes with the E4OD & 460 Ford had the three digit error code on some 1990 and all E4OD & 460 F-series in 1991. But I have heard of some 1989 truck that had the three digit error codes also. But they had to have the E4OD transmission in them.

You need to put a fuel pressure tester on the fuel rail before replacing any parts to see what the fuel pressure is.

You should have 30-34psi fuel pressure at idle (depending on your vacuum at idle) and around 40-42psi at WOT. If you ground pin #6 on that test connector you replaced with the key on and the engine not running you should get 45psi.

thunder47for · 08-04-2013, 11:57 AM

I talked guy that I got this bounder from and every thing is the way it came from the dealer he told me the port got sheared off and he had the plug and all I did was solder and shrink tube it back on what luck he would still have it I just bought it two weeks ago I also have a auto x ray I prided big money for it years ago but the cheaper tester is better for testing this 460 ford

thunder47for · 08-04-2013, 04:31 PM

Well I checked with the fuel pump jumped out 40 psi new o2 sensor I take the bounder for a ride no lite for the first 5 miles then it comes on it cools down no lite

subford · 08-04-2013, 05:53 PM

40psi with pin #6 to ground seems a little low with the engine not running and that would mean when running the fuel pressure would be low.
So I would say you need a new fuel filter or fuel pump.

The the error is coming on after the engine is warmed up and the computer goes into closed loop. That is when the computer checks the O2 sensor.

jamesrxx951 · 08-04-2013, 07:40 PM

Quote:

Originally Posted by subford

40psi with pin #6 to ground seems a little low with the engine not running and that would mean when running the fuel pressure would be low.
So I would say you need a new fuel filter or fuel pump.

The the error is coming on after the engine is warmed up and the computer goes into closed loop. That is when the computer checks the O2 sensor.

The workshop manual states that the spec is 35-45 PSI when key on engine off and 30-45PSI when the engine is running. The real test is to start the engine and you should have a minimum of 30 psi. When the engine is running, remove the vacuum line to the fuel pressure regulator. The pressure should be higher at this point. It typically will be around 40-45 psi. If that is ok then go WOT acceleration till the shift point. The pressure should never drop below 30 but it should be +or- 3 PSI of the fuel pressure noted with the engine running and vacuum line disconnected.

subford · 08-04-2013, 09:08 PM

Quote:

Originally Posted by jamesrxx951

The workshop manual states that the spec is 35-45 PSI when key on engine off and 30-45PSI when the engine is running. The real test is to start the engine and you should have a minimum of 30 psi. When the engine is running, remove the vacuum line to the fuel pressure regulator. The pressure should be higher at this point. It typically will be around 40-45 psi. If that is ok then go WOT acceleration till the shift point. The pressure should never drop below 30 but it should be +or- 3 PSI of the fuel pressure noted with the engine running and vacuum line disconnected.

Yes I know the what the manual says but the manual is dead wrong.
I stand by my real world reading above as I have worked with over 500 of these systems from 1986-1995 Ford trucks.
The my above readings have always turn out to be right.
The above readings you posted do not make any sense at all.
If you get 35psi with key on engine off with pin #6 grounded you have a big problem.

jamesrxx951 · 08-04-2013, 09:25 PM

You can say anything you want but it seems to be incorrect. What you failed to mentiontion is the REAL test and that is engine running and wot. Base pressure koeo is good to know but only tells you the fuel system makes pressure koeo. Cannot tell you how many misdiagnosis I had to fix correctly because fuel pressure was not monitored during actual driving conditions. Its nice to know that you feel the manual is wrong with so many other techs using it and diagnosing correctly. Guess engineers don't know either.