Ford 460 Class A question??

[dad4papa2]

Hi my name is Dennis. I am hoping I can get some suggestions on fixing my problem. I have a 1996 Damon Intruder with a 460 Engine in it. This motor has performed flawless for 9 years since I have owned it. I do regular service as air cleaners, oil changes and little needs that arise. Here's my Question.

Yesterday I get in it to take it for inspection for new plates. It cranks up without fail as always and I let it idle for about a minute or so while I get it prepared to drive. All of a sudden it dies and for the first time in 9 years the Check Engine light comes on. Now it won't start. It cranks good but just won't fire up.. I am pretty sure it has about a half tank of fuel in it but now the gauge is on the 3/4 mark full and does not drop down when I shut the key off.

So any ideas as to where to start?? I have looked all over for a place to scan the system with my scanner but haven't found one yet.

I did find a hose that had deteriorated and cracked. I repaired it temporarily to see if that helped but it didn't. I runs from the back of the engine about mid ways and goes to a valve of some kind on top of the valve cover. then it runs down along side the engine toward the bottom. I will try to get a picture soon.

So with what I have said where do I start.

Thanks Much Dad

[Stim]

Tank pressure sounds like an emissions problem.
Fuel tanks are non-vented but pressure is controlled through canister, vacuum hose.
Not sure how that would cause no start. ???

[dad4papa2]

Something else I have just noticed. The gas cap is super hard to get off. When I do get it to turn there seems to be considerable amount of pressure released.

[dad4papa2]

Ok I'm back! Got kinda side tracked on another project.

Checked the Ground cable where it connects to the frame. Cleaned it as it was dirty and appeared to not be making good contact. Got in motor home and after 2 days of not starting it fired over and was running instantly.

Shut off before engine got heated up and installed Fuel pressure gauge. It showed 0 pressure as I had relieved the pressure by removing the little valve stem in the schrader valve.

Connected the fuel pump gauge and turned on the key . Gauge went immediately to 39 pounds then dropped pretty quick to 35 pounds. It stays there for several minutes. After about 15 minutes went back to check it and it was still at 28 pounds.

Now I turn key back on and it does same thing.Then I try to start the MH and the gauge doesn't move at all. It stays on the 35 lbs.

So Still no spark. I would try the hot wire trick but need to do some searching on how to do that.

Also I will try and locate the ecm switch and figure that one out.

I will follow up later.
Dad

[enblethen]

Try applying power directly to the coil. "hot wire it"
Verify voltage to the ignition module
See if it fires. Could be something likje bad ignition switch or loose connector.

[dad4papa2]

That’s what shutting off I think. When I crank it I have no spark at the coil. I also find the ignition module. More later.
Thank so much for all the help.
Dad

[enblethen]

No, low fuel pressure should not shut off ignition.

[dad4papa2]

Thanks jyork, I have one I used while racing. I’ll find the connection and check it. If I have no fuel pressure will it shut off the fire to the engine?
Thanks Dad

[Jrork]

dad4papa2 wrote:
Thanks for the info to all. I went out this morning and here we go again. I will again start tracking all this info. Will let you all know what i find. Started fine a couple times yesterday and now this morning shaking my head again.

Will get back on it Monday.
Thanks Dad- Stay Tuned lol

DAD, please beg, borrow or steal a fuel pressure gauge. It plugs into a fitting on the fuel line right on top of the motor and will instantly tell you if you have a fuel pressure issue. I hate Harbor Freight but for this dealio, I picked up one for $19 and within a couple minutes was able to determine if I had a fuel pressure issue.

https://www.harborfreight.com/fuel-injection-pump-tester-62623.html

[dad4papa2]

Thanks for the info to all. I went out this morning and here we go again. I will again start tracking all this info. Will let you all know what i find. Started fine a couple times yesterday and now this morning shaking my head again.

Will get back on it Monday.
Thanks Dad- Stay Tuned lol

[John_Joey]

The gal is over 20 years old, thinking the old style fuel pump has been long replaced. It is often talked about on this forum like it is some new issue. If you got 20+ years out of an OEM fuel pump, then that's some kind of known issue. A fast check is to see the wiring. The new wiring to the updated fuel pump I believe is 4 not 3.

[T18skyguy]

There was a recall on the fuel pumps during those years. If that's it, you want the new pump they call the "turbine" pump. The old pumps ground themselves out and fail. You say it's a 96 motorhome, that usually means a 95 chassis unless your sure otherwise. Another issue is the electrical guts in the distributor are known to go bad. Replace the pickup/condenser in there might help.

[mowermech]

John&Joey wrote:
Find the ignition module. It should be either on the distributer or the firewall. Probably on the firewall. It could be that the module over heats and shuts down. Put an ice pack on it and then try and restart the engine.

We had a 1995 Class C with the 460. It would shut down for no apparent reason, then start and run just fine after 15 minutes or so. I replaced the ignition module with a known good used one, and the problem went away.
I traded it for the coach in my sig., and have had no problems since.

[John_Joey]

Find the ignition module. It should be either on the distributer or the firewall. Probably on the firewall. It could be that the module over heats and shuts down. Put an ice pack on it and then try and restart the engine.

[Stim]

Fuzzy Knight wrote:
You may have the beginnings of a bad fuel pump. 96 is a long time for an electrical pump to live. This is a fairly complex problem as the pump is in the tank. Next time it does not start or quits leave the key on and crawl under to see if you can hear the pump running.

The pump won't run without oil pressure. (Safety feature)
It will run for a short period of time to get fuel up for starting from relay.
If you can, listen while someone turns key on and off for short period of time.

[Fuzzy_Knight]

You may have the beginnings of a bad fuel pump. 96 is a long time for an electrical pump to live. This is a fairly complex problem as the pump is in the tank. Next time it does not start or quits leave the key on and crawl under to see if you can hear the pump running.