I'm having problems with my 95 F150 4.9 4X4. it has always been a good running truck and I stand behind the 4.9 with the same words as others, "It's bulletproof!" Now for the problem:

It starts hard, but only from cold condition in warm weather and only on the front fuel tank, switch to the rear tank and it snaps to attention.

When driving at 50 to 60 mph, around 1600 rpm at a steady throttle the engine stumbles, increase or decrease throttle and all is smooth, but set the cruise control, well, hang on you're in for a rough ride.

The fuel mileage has gone from the expected "not too great" to a horrifying under 200 miles per tank.

A check of the codes KOEO returns 111, all okay.
A check of the codes KOER returns SPOUT OPEN, sorry I didn't get the raw code number.

A physical check of the SPOUT found it in place and when checked with an ohm meter shows no resistance or a short condition as expected.

Any ideas? Thanks,

Jack

 

If it only happens on the front tank, then it sounds like the front pump is going bad.

 

You should check your fuel pressure, from both tanks, KOEO and KOER, and observe how fast the gauge bleeds down after the engine is shut off (for both tanks). It sounds like the front pump isn't holding pressure very well after the key is off.

Does the stumble at cruising speeds happen regardless of which tank you're on? More than likely, it's being caused by dirty injectors. Pick up a couple large bottles of injector cleaner, and run your rear tank until it's almost empty. Go to the gas station, and put both bottles in the rear tank, and then add 4 gallons of gas. Drive around on the rear tank for 30 minutes, and then park it for the night. The next day, you should notice an improvement if it's the injectors. If the problem is unchanged, email me.

Take care,
~Chris

 

Forgot to answer about your code.

Check your ignition timing with the spout disconnected, and make sure it's at 10 degrees advanced. Sometimes these engines will throw that code when the base timing is advanced beyond 12 degrees.

 

The hard starting only happens with the front tank, but the stumble at highway speeds happens with either. I've been told that this may be the switch on the dash. I plan on purchasing a pressure today after work and I'll report later on how that turns out.

Honestly if it turns out to be bad fuel pumps I'd be thrilled to change them, I just want my truck to run good again.

I hitched my trailer to her on Monday, loaded the tractor mower combo and she pulls just fine. That combo makes the GCVW somewhere around 5.5 tons. I use my Ford.

 

>You should check your fuel pressure, from both tanks, KOEO and KOER

I'll check this tonight. I was so busy this weekend I didn't even get time to check the email.

>Does the stumble at cruising speeds happen regardless of which tank you're >on?

Either tank, they both react the same at higway speeds.


>Pick up a couple large bottles of injector cleaner, and run your rear tank >until it's almost empty.

I'll get the stuff tonight whaen I get the pressure tester.


Thanks for your input.