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jonsha97 · 10-07-2014, 10:25 AM

Running rough, cutting out. Diagnostics come up with nothing. Recent tune-up. What could be the problem? Totally frustrated!

IdahoSRT10 · 10-07-2014, 10:49 AM

What work was performed during the tune-up?
plugs
plug wires
fuel filter
new fuel

tom77hmstd · 10-07-2014, 02:20 PM

Fuel pump. Probably has 2 a low pressure in tank, high pressure on l/s inner frame rail.

Duoglide1 · 10-07-2014, 09:31 PM

I had a 92 Dutchmen with the Ford460 and when mine did it it was plugged fuel filter. It was on the inside frame rail under the drivers side.

Seitz372 · 10-08-2014, 08:15 AM

There are lots of things that could cause those symptoms. You mention diagnostics were performed. What diagnostics were actually done? Do you mean they plugged a scanner in to check for codes? I can t recall if that year would be OBD-II or not? If not a scanner probably wont be much help. EGR issues, vacuum leaks, internal engine issues are just some of the many things that can cause an engine to run rough. I would suggest posting your problem over at Ford-trucks.com or fordf150.net They have specific forums about the 7.5L ford. They also have forums about the F-53 chassis which you most likely have under your rig.

TQ60 · 10-08-2014, 06:18 PM

Get vacuum guage and see what it indicates.

Check for loose or cracked hoses as they can make a valve stick.

Check egr.

Learn how to read codes.

If odb1 you short out certian pins and count flashes of check light

subford · 10-09-2014, 07:05 AM

As you also posted in a class "C" Forum I will guess you have a "C" RV with an "E"-series chassis.

As stated above you have the OBD-1 Ignition system and you can ground the STI wire and count the flashes in the cluster.

If you disconnected the battery then the codes that will tell what is wrong when you were on the road are gone from the CM part of the self-test.

Did the MIL come on during the problem you had?
Note some call the MIL the CEL.

If so then codes will be stored in the CM if you did not disconnect the battery.

jonsha97 · 10-09-2014, 03:33 PM

When I say diagnostic, I mean on a large sun screen not a code reader. no codes have come up including low fuel pressure on either test I.E.(fuel filter). I'm gonna change out the fuel filter any how and report back. Poke and Hope. I think with this help I'm gonna find it. THANKS Jon

BFlinn181 · 10-09-2014, 04:51 PM

Running rough, cutting out aren't things usually picked up by ECU codes in a 1994 engine. You mentioned a 'large sun screen,' I guess you mean a 'Sun engine analyzer.' According to what model Sun engine analyzer was used and the number of hook ups made, it could have shown plug wires, plug, spark, and timing advance. If none of those were out of spec, how about vacuum? Rather than throw parts at it, you need a competent tech to diagnose the problem.

jonsha97 · 10-10-2014, 12:24 AM

subford; don't leave me now, you're on to something, I'm just trying to digest your knowledge., Appreciate the pictures,abreviations of parts and even the color code, but it's over my head or maybe I'm making it complicated.Basicaly, each coach and size motor requires certain moduals/componates and their seems to be many.In order to repair the problem I hafta find replacement parts.Ebay lists many parts(ecu modules)with many different numbers and I got one coming that's from a 460 excursion with different numbers that I'm reading off my possible broken part.I need direction and sequential steps in order to fix this myself. Right now I'm learning the computor. Talk to you tomarrow. Jon THANKS

subford · 10-10-2014, 05:58 AM

To start with with Ford never made an Excursion with a 460 engine. A Computer from any Excursion would not work or even plug into your E-series RV. As stated above your E-series RV is an OBD-1 and any Excursion would have a different type Ignition system

You said you had it on a 'Sun engine analyzer". Sun was bough out by Snap-On years ago so this was an old type analyze. I do not think it would show more the primary and secondary ignition waveforms on the Ignition side.

It does not sound like you ever had your RV hooked up to a code reader. You never came back and said if you disconnected the battery after you had the problem before having it checked. I also get the impression that who you had look at it was not a professional shop and maybe just a friend.

subford · 10-10-2014, 09:43 AM

By the way you only have one Fuel Pump and it is located inside the tank.
Sounds like you may have a bad pump or the strainer in the tank is picking up junk.

That is why we did the codes to make sure it is not an Ignition issue then if not you can go ahead and check the fuel pressure on the road.

BFlinn181 · 10-10-2014, 10:39 AM

I find the OP very frustrating to help. He seems to be jumping all over the place and only telling us part of the story. He started by saying, "Running rough, cutting out. Diagnostics come up with nothing. Recent tune-up." When asked about what the 'tune up' entailed, we got nothing. When asked what the diagnostics checked, we were told it, "I mean on a large sun screen not a code reader. no codes have come up including low fuel pressure on either test I.E.(fuel filter)" I asked if by 'sun screen' he meant 'Sun engine analyzer.' and what did it specifically analyze? He came back with, "I hafta find replacement parts.Ebay lists many parts(ecu modules)with many different numbers and I got one coming that's from a 460 excursion with different numbers that I'm reading off my possible broken part.I need direction and sequential steps in order to fix this myself. Right now I'm learning the computor" Now he's talking about broken parts, ECUs, and 'learning the computor. (SIC)' Are you talking about learning the engine ECU or your home computer? I agree, you need direction and sequential steps because you seem to be jumping all over the place and are doomed to just throw parts at the problem.

Replacing the ECU won't fix it, because it wouldn't run if the ECU was bad. Perhaps a dirty connection would be 'fixed' by doing a R/R of the ECU, but maybe not. A bad O2 sensor can cause roughness. Plugs, (if not changed in 'tune up') should be examined:
NGK Spark Plugs USA

Plug wires, coil, distributor cap, and on and on, can all cause 'running rough, cutting out' (misfire??)

The suggestions to change fuel filter or fuel pump are about as useful as the 'bad ground' recommendation on anything electrical. Yes, it could be the issue, but measuring fuel pressure and volume should be done before just replacing parts.

A dirty fuel system could be part of the issue, but again, don't just dump cleaners in the tank and expect everything to heal itself.

You need to find a good book on your engine and go through the trouble-shooting guides they almost always have. Jumping around and fiddling with different things is like a blind pig, even they find an acorn now and again, but it's inefficient and a time and energy consuming method to solve problems.

jonsha97 · 10-10-2014, 01:30 PM

Quote:

Originally Posted by jonsha97

Running rough, cutting out. Diagnostics come up with nothing. Recent tune-up. What could be the problem? Totally frustrated!

Hey, If you and your friend are through bashing me,maybe I should back out of IRV2 FORUM and take my problems to someone who understands inexperienced RV owners cuz I'm not as smart as you. JON