1990 Bounder Diagnostic Port Dilemma

[mpaton]

Originally Posted by thunder47for

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

I've been surprised before, and I'm sure I will be again, but I believe the code reader. Are you able to locate the ECU code on the 60 pin connector? The 3 or 4 character code in a much larger font size. That would tell us if your ECU had been replaced with a later one.

And do you have an E4OD transmission?

While the Ford trucks got the injected 460 and the E4OD in the late 80s, I had believed that the F53 chassis didn't get the E4OD till around 1993 or so, with the C6 transmission being used.

[mpaton]

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.

Without the engine running, 40psi sounds pretty much exactly correct, the actual figure being 39psi.

Originally Posted by subford

So I would say you need a new fuel filter or fuel pump.

He may or may not need a new filter or pump, but you cannot infer that from this test. You appear to be assuming, perhaps based on your own experience that if the spec is exactly met with the engine off, then the spec will not be met with the engine running.

I'm with James on this one, the requirement is 39psi above manifold pressure at all times, including at high engine output. Only a full throttle test can provide this.

[jamesrxx951]

Originally Posted by mpaton

He may or may not need a new filter or pump, but you cannot infer that from this test. .

Agreed and the fuel filter being less likely based on that test. When the engine is off, a partially plugged fuel filter will allow the fuel pressure to read correct. This is because the other end of the restriction is not loosing any pressure so both side equalize. Only when the engine is running or at WOT would this be evident. Ran into this a few weeks ago in a Diesel where someone installed 4 injectors for a drivability issue. The problem did not get corrected. So they quoted the customer 4 more injectors. Customer declined. I received the van and one of the first things I did was to check fuel pressure. It appeared ok until I drove it. Went down to 3 PSI. Performed a fuel line restriction test to test the fuel pump and it was pulling 20 inch's of vacuum on the inlet side. Replaced the intank pick up and cleaned out the tank from the excessive debris that was in there and pressure was correct under WOT.

[subford]

Originally Posted by mpaton

And do you have an E4OD transmission?

While the Ford trucks got the injected 460 and the E4OD in the late 80s, I had believed that the F53 chassis didn't get the E4OD till around 1993 or so, with the C6 transmission being used.

They had the E4OD in 1990 F53.
As far as I know all E4OD trucks (RVs) had three digit codes.

Here is one with the E4OD:
New & Used Bounder Used Cars financing For Sale Granby 80446 Winter Park Granby CO - High Country Motors

Quote:
"Posted By: RLS7201 on 05/04/13 11:27am

All F53s 1988 to 1997 were equipped with an E4OD transmission. The transmission case is designed for 4WD and uses the deep pan and long transmission filter tube. A ZF emergency brake is bolted to the flange where a transfer case in normally installed on 4WDs.
It has very slow, soft shifts and it's service life can be extended with a Banks Transcommander.


Richard"
/

[mpaton]

Originally Posted by subford

They had the E4OD in 1990 F53.
As far as I know all E4OD trucks (RVs) had three digit codes.

Here is one with the E4OD:
New & Used Bounder Used Cars financing For Sale Granby 80446 Winter Park Granby CO - High Country Motors

And here's one without:
1991 Flair By Fleetwood 25Y for Sale - A808 - PPL Motor Homes
You can see the older style steering wheel that goes with the C6.

Also I have an ECU from a 1990 Ford truck (likely not an RV) Code SOJ that has 2 digit codes, and an E4OD. And guess what else? Closed loop is NOT calibrated out.

Originally Posted by subford

Quote:
"Posted By: RLS7201 on 05/04/13 11:27am
All F53s 1988 to 1997 were equipped with an E4OD transmission.
Richard"
/

So I've found at least one that didn't. I'm sure it was OFFERED, but this statement is like saying that all vehicles from 1996 and after are OBD2, whereas we in the RV community know that's not so. I gather some RV makers were using the C6 with an overdrive, and didn't want the E4OD.

[subford]

Originally Posted by jamesrxx951

Agreed and the fuel filter being less likely based on that test. When the engine is off, a partially plugged fuel filter will allow the fuel pressure to read correct. This is because the other end of the restriction is not loosing any pressure so both side equalize.

None of this is true.
With pin #6 grounded and the key on and the engine not running you will have a maximum flow of fuel and same amount as if the engine was running from the fuel tank to the engine and back to the fuel tank. Except it will be less flow if the engine was running going back to the tank.


This is because the fuel pump will put out about 98psi fuel pressure to a closed head. Then the Fuel Pressure Regulator (FPR) will then bypass fuel back to the tank to maintain the 42-45psi fuel pressure on the fuel rail.
So fuel flow is just as great as if the engine was running under WOT.

So with this pin #6 test the fuel filter, fuel pump and the FPR are all tested.

[subford]

Originally Posted by mpaton

And here's one without:
1991 Flair By Fleetwood 25Y for Sale - A808 - PPL Motor Homes
You can see the older style steering wheel that goes with the C6.

If you read down you will see it also has the E4OD transmission.

What does the older style steering wheel have to do with the transmission?
The OD switch would have been on the dash.

[jamesrxx951]

Originally Posted by subford

None of this is true.
With pin #6 grounded and the key on and the engine not running you will have a maximum flow of fuel and same amount as if the engine was running from the fuel tank to the engine and back to the fuel tank. Except it will be less flow if the engine was running going back to the tank.


This is because the fuel pump will put out about 98psi fuel pressure to a closed head. Then the Fuel Pressure Regulator (FPR) will then bypass fuel back to the tank to maintain the 42-45psi fuel pressure on the fuel rail.
So fuel flow is just as great as if the engine was running under WOT.

So with this pin #6 test the fuel filter, fuel pump and the FPR are all tested.

You are 100% wrong. You may need to spend more time under the hood testing. There is a large difference between the what the pump is capable of producing as far as PSI and the amount of volume it is capable of this is the GPH rating on the pump. Some of this does do hand in hand but not all. A plugged fuel filter WILL cause low fuel pressure at WOT and not at idle. This is an absolute fact. If you want proof it will not be hard to post the picture of a plugged fuel filter that I have that showed normal fuel pressure at idle but not when driving.

[jamesrxx951]

Subford:

If your statement was remotely correct, why would Ford Motor Company have a pinpoint test that list exactly what I said and pay the tech to do the test? If it was just as easy as putting a gauge on the fuel system and do your test, it would save them thousands of dollars to eliminate that labor op.

EFD5 CHECK FUEL PRESSURE WITH ENGINE LOAD

• Fuel pressure test kit installed.
• Disconnect vacuum hose at the fuel pressure regulator and plug it.
• Observe fuel pressure while driving vehicle with heavy accelerations.
• On Type 2 (Dual Tank System) perform test for both tanks.

Does fuel pressure reading remain within ± 3 psi during the test?

[subford]

Originally Posted by jamesrxx951

You are 100% wrong. You may need to spend more time under the hood testing. There is a large difference between the what the pump is capable of producing as far as PSI and the amount of volume it is capable of this is the GPH rating on the pump. Some of this does do hand in hand but not all. A plugged fuel filter WILL cause low fuel pressure at WOT and not at idle. This is an absolute fact. If you want proof it will not be hard to post the picture of a plugged fuel filter that I have that showed normal fuel pressure at idle but not when driving.

It sounds to me like you are talking about a non fuel return system and that does not apply to our fuel system with the 460 engine.
When the fuel pressure regulator is sending fuel back to the tank it is sending volume (flow) to get its regulated pressure. So the GPH going back to the tank is high and a plugged fuel filter will show up.
As far as time under the hood I have spent over 54 years under the hood working on Fords.
This test has worked hundreds of times for us over on the Ford site with poster that have taken their trucks to Ford dealers with no results.
I have over 15,000 post over there and have been thanked hundreds of times for the test.
It is also in a few after market repair manuals for our era Trucks and RVs.

[jamesrxx951]

Originally Posted by subford

It sounds to me like you are talking about a non fuel return system and that does not apply to our fuel system with the 460 engine.
When the fuel pressure regulator is sending fuel back to the tank it is sending volume (flow) to get its regulated pressure. So the GPH going back to the tank is high and a plugged fuel filter will show up.
As far as time under the hood I have spent over 54 years under the hood working on Fords.
This test has worked hundreds of times for us over on the Ford site with poster that have taken their trucks to Ford dealers with no results.
I have over 15,000 post over there and have been thanked hundreds of times for the test.
It is also in a few after market repair manuals for our era Trucks and RVs.

No I am talking about this system. Return less systems are also affected but you can monitor the fuel pump driver in some cases to see what it is doing. I really don't care how many years you have in the business because if have worked with guys that have been in the business that long and longer and have been easily proved incorrect. Working at Ford allowed me to work with many other long termers that also needed coaching to allow their diagnosis to go in the correct direction to allow a correct diagnosis the first time.

The funny thing is, is i just had a 1992 Lincoln town car that has the same type of fuel system as the 460 and pretty much every other Ford of that time. It would almost stall on acceleration. Fuel pressure was correct and at idle it would show 32 PSI like it should. Ramp up the throttle and it would drop to 10 PSI. The culprit was damaged fuel lines. Allowed correct fuel pressure with no or little load but when the injectors needed to duty cycle higher and faster, the restriction would not allow enough fuel to flow through it to maintain pressure.

[thunder47for]

This is really got me scratching my head every time I take this down the road it goes farther before the check lite comes on so far I changed the cooling sensor o2 sensor , fuel filter tomorrow I will try sea foam to see if some injectors are screwing up causing to get a lean fault next I will spray the vacuum lines with carb cleaner maybe a cracked line but I think it the injectors because every time I go farther before the lite comes on I'am running out of Ideas

[subford]

Sea Foam is OK to put through a vacuum line into the intake but I would not use it in the fuel tank or oil.

To clean the injectors hook the injector cleaner to the fuel rail, remove and plug the vacuum line to the fuel pressure regulator.
Remove the fuel pump relay.
Then keep the cleaner pressure below 38psi and run the engine on just the cleaner until the cleaner can is empty.

[thunder47for]

A friend brought his snap on scaner over and we checked it out going down the road with fuel pressure gauge attached and the pressure was 32 at idle when we jumped on it it went to 40 psi and the code was o2 sensor was not switching he thought it was a bad new o2 sensor ?