Many thanks in advance on whatever help or input given on my situation. More heads are better!

My truck is an F250, 5.8 351 with 186,000 miles. Thought it was boneyard time but after looking at new truck monthly payments I fixed it up to give myself more breathing space. Work done: New head, body work and re-paint, new shocks, assorted odds and ends fix. I really thought the problems would be over. Think again!

Then the lack of power and stall outs started. I changed the TPS and coolant sensor. I put in a new side tank (which had been leaking forever) with a new sending unit and pump. I changed the fuel filter. Still had loss of power after 10 minutes of driving with a 10ft utility trailer on either gas tank. Some backfiring/popping to go along with it. I changed the fuel relay but no go. Tomorrow morning I'm replacing the high pressure pump on the rail. If this doesn't do it I'm at a loss for what next.

The codes read 32 an then 11. Could the EGR sensor malfunctioning cause this condition? The truck runs rough at idle and I thought this was probably due to the bad EGR sensor but I don't know if the power loss while driving could be one in the same.

 

For all that a EVP sensor costs (30 bucks), go ahead and get one. It wouldnt hurt to replace it anyway even if it wasnt the problem. Replaced mine and in combination with relacing the TPS got 2 extra MPG. I had pulled code 32 on my 93 and when I replaced the EVP, the code went away.

 

I'll replace the EVP sensor and see what goes with the codes. That aside, the high pressure pump finally fixed the main loss of power. However the new fuel relay was beat right from the store. Truck would go 100 ft, lurch go another 100 ft lurch. Obviously electrical. Put the old fuel switch back in and no more lurch.

In any event the truck is running fairly well. But I'm compulsive! Here's the symtoms. There is a lack of smoothness when accelerating hard with the trailer but not like the fuel pump issue. More like the spark and the fuel to the injectors aren't exacting in sync. Smooth but irregular if that makes any sense. I put in some injector treatment and I'll see what'll happen. Full power would be nice to have again even though the truck is turning 20 yrs. old.

Any help would be appreciated.

 

I need help.

This truck is running worse than ever. The fuel delvery from the tank seems to have been made better. But now the engine stumbles like it has a major vacume leak at idle. All the vacume lines seem ok. If I floor the accelerator from a stop, many times the there will be lots of popping/missing as if the timing is way off. Irratic acceleration - lots of surging and then what feels like power loss The timing at idle is very erratic - jumping around alot.

This truck is driving me nuts. I get one thing fixed and another problem. I'm out of ideas and about out of cash. This is my work vehicle and I need to get there ASAP.

What could this be?

 

Whats the fuel pressure read running? Any engine codes? Sounds like a bad fuel pressure regulator if there are no codes. Pull the vacuum line of and see if there is not any fuel present. You can use those $4.00 air pressure dial gauges to check fuel pressure. It should be around 35psi at idle and if you pull the vacuum line off it should go up to around 40psi.

 

No gas is present in the vacuum line to the regulator.

I'll do a reading and post.

Can I clip on a tire gauge - the type with the hinged thumb lever and read it that way?

 

I just bought one at walmart that you just push on and hold it. It was like $3.95. If you want you can invest in a real fuel pressure gauge but If you only drive Fords you can get by with the tire gauge type. The first thing I check for when working on the engine is the fuel pressure. It is pretty critical.

 

Will do.

Thanks

Also, it's reading code 32.

 

Sounds like a lean miss to me.

That said, a couple things it could be. The 32 EVP is still pointing at the EGR. Did you replace the sensor yet? If so, and still getting the EVP code, it may mean the valve is stuck open. Check it for operation with a vacuum pump, but do so carefully. Do not exceed 20 inche vacuum on the valve motor.

More to the point, it's time to check it good for vacuum leaks. I find a propane torch (unlit) VERY handy for that. DO THIS ONLY IN A WELL VENTILATED OPEN AREA OUTSIDE!!!! Direct the gas around the EGR valve, all around the upper and lower intake mating surface, and anywhere along any hose connected to the vacuum tree. If there's a leak you'll find it, with one possible exception. If your power brake booster has failed internally, you won't be able to detect that with the propane. Normally, though, you can hear a sucking noise inside the cab when the booster fails. If it's elsewhere, however, when the propane goes in instead of plain air, the idle will smooth right out. Check out my gallery for some photos of a problem I had with similar symptoms. 3 Ford Stealerships worked on my truck at a cost of over $1400 and still couldn't fix it. I spent $20 for gaskets and another $20 on Seafoam cleaner, cleaned the TB and injectors, and VOILA! Truck runs like a brand new one.

 

Old Paint,

I wish that had been the problem!

The post you responded to was a little old. Since then I replaced the engine with a remanufactured 351. i found that my #2 cylinder was destroyed with some foreign object having been injested.

Now the truck runs great - except at idle. I replaced wires, cap, rotor,plugs,distributor and had the injectors professionally cleaned and pattern tested to within 2% of each other.

Truck runs smooth when setting base timing and rough when the spout is re-connected. Someone suggested the idle air control as a possibility.