460 Ford engine stalls when put in gear

[Geocritter]

Hi all y’all,
Wouldn’t you know it, I’m ready to start out on a 900 mile journey and my previously good running 1994 Ford 460 V8 engine decides to act up. Here’s what I know:

When I purchased the RV last April it ran fine, I parked it at a friends for a few weeks and whenever I had to move it, it started and ran fine. In June I drove it 1/2 mile to a nearby RV park where I’ve lived in it since. Once in July I started it up and drove it a short distance to take on propane, it ran fine. Since then I’ve started it up periodically maybe every other month. I’d let it warm up and then turn it off, it’s always run fine (of course all I did was idle it).

Yesterday I started it up to drive it the 1/2 mile back to my friends place and it started up after a prolonged cranking. After it started it seemed to idle okay but it had a miss when I’d feed it gas and the exhaust smelled like it was running rich, though it was not blowing any soot or anything like that, just a tell-tale odor. I let it warm up and the minute I put it in gear it died. Tried again several times until finally I put my left foot on the brake, raised the RPMs slightly (no tach, so I don’t know how much). With the higher RPM I was able to get it to stay running in gear, whereupon I carefully drove it to my friends, never letting the RPM’s drop to idle when I’d stop.

I haven’t torn into the engine yet, I’m hoping for some useful input before I do that. At this point I’m thinking it might need a new O2 sensor or some plugs and/or plug wires or the coil has gone bad.

I hate to ask for help with this, I’ve worked on gasoline engines all my life, even professionally while I was in college, but I just don’t have the time to do a lot of guessing at this point and I really don’t have the money to take it to a mechanic.

Steve

[dakdave]

Is idle speed low in park? Try cleaning throttle plates,idle is controlled by bleeding air around plates. If they are dirty and idle will be low and when u put it in gear engine cannot catch up and they die.Worth a try

[wolfe10]

Remove the gas filler cap and SMELL IT. Does it smell like gasoline or does it smell like it has "turned"?

[allbrandauto]

If its the egr valve tap on it lightly with hammer if it smooths out that's your problem what type of fuel injection syt do you have you said vacume hoses melted you have a map sensor that has a vacume hose and 3 wires going to it unplug the hose at the sensor should have manifold vacume if not it will run rich

[Geocritter]

RLS7201 wrote:
Another possibility is the EGR valve not closing completely at idle. Starting the engine and not driving it will due more harm than good. The oil will not get hot enough and it may cause the EGR valve to stick open from carbon build up. Don't start it unless you are going to drive it.

Richard

I googled (bad) "EGR valve symptoms Ford" and you may be right and I'll check it out the this afternoon.

Steve

[Geocritter]

Bird Freak wrote:
You can add all the additives and cleaners you want. Drain the tank and put fresh gas in it. I deal with this a lot in my business.

You might be right but I hope not. What can I do with 50 gallons of old gas in the tank and only 5 days away from the start of my journey. What I should've done was syphon my gas 5 gallons at a time and burned it in my car (augmented by 15 gallons of fresh gas in my 20 gallon tank). Why is hindsight always 20/20?

Steve

[RLS7201]

Another possibility is the EGR valve not closing completely at idle. Starting the engine and not driving it will due more harm than good. The oil will not get hot enough and it may cause the EGR valve to stick open from carbon build up. Don't start it unless you are going to drive it.

Richard

[Bird_Freak]

You can add all the additives and cleaners you want. Drain the tank and put fresh gas in it. I deal with this a lot in my business.

[Geocritter]

Hi all y'all,

Please no one be offended by my remarks, I'm simply brain-storming here looking for a solution. I was hoping that the symptoms I had might point to some classic and common (ie: easy to diagnose) failure.

No smoke when I start it up, and yes I do know what to look for. Years ago I had a 1991 Caravan with a cracked head, drove it like that for a month before I replaced the engine. Every time I'd fire it up I'd get a huge cloud of white smoke that'd dissipate almost instantly (and smelled like anti-freeze).

It might be a vacuum leak, I rerouted some lines and wires that were lying across the tube for the EGR valve and were melting onto the hot tube. Still I wonder about that rich-mixture odor I noticed while it was running. To me it sort of contradicts a vacuum leak.

It has a new inline fuel filter.

I've been wondering about having bad gas. It had about 50 gallons in it when I purchased it from the dealer and no telling when that gas had been put in. Now that it's sat for 7 months, what may have been marginally good gas is now bad gas. I'll try adding a few bottles of SeaFoam.

Thanks for the suggestions and comments, I appreciate it. Right now I'm just a little spooked, sort of a bad omen type of thing (knock on wood! LOL).

Steve

[Bird_Freak]

I will bet bad gas also. I see it here all the time. I bet you need to drain it and refill with fresh with SeaFoam in the gas.

[John_Joey]

Old gas, put some SeaFoam (1 can per 20 gallons) into it. Start it up and let it idle for a short time to make sure the Seafoam gets everywhere in the fuel system. Shut it down for 24 hours and see where you're at.

[SPRING_STREET]

in line fuel filter !

[K_Charles]

Look for a vacuum leak.

[nelson]

When it starts is it smoking at all and if so what color is it. If it is, check the oil and the antifreeze. I am thinking it might have a blown head gasket, Hope I am wrong.