Mystery Machine
 

Ok. Here goes. First off I have a 2001 E250 with a 5.4l engine and automatic transmission with 215000 mile.
In December I had a misfire on a couple of cylinders and I ended up burning up the cats. Misfire was corrected with new cop's and plugs. New cats (all 3). Shortly thereafter got the lean on bank one and 2 code. Shop said low fuel pressure so fuel pump and fuel filter replaced. No change. New shop found intake gasket leak that was causing vacuum and coolant to leak on cop's. Intake gasket replaced along with dpfe, maf sensor, throttle body, tps, air filter, egr valve, and all vacuum hoses. I have driven over 1500 miles since and have no check engine light and the mechanic said there are no stored codes.

Ok. To my problem. If I and just driving through the neighborhood I have no problems but if I try to climb a hill it struggles. I go from 70 mph to about 45 on a hill. The mechanic said the transmission is slipping. I took it to the transmission shop and they said there nothing wrong with it and that it is engine related.

Any ideas?

I'd suggest a third and forth opinion; one from each specialist.

If the transmission is slipping it will turn the transmission fluid black and stinky in one mile. Is the fluid black and stinky, or is it red and smell like oil?

I forgot to put that on the list. The transmission was flushed and the filter was changed. The tech said it looked a little dirty but not burned.

I have very little experience with the 5.4.

(351W is my choice engine)

But, with 215K on the clock, I would say that engine is getting tired, that's why your losing power going up that hill at 70mph.

There could be other underlying problems causing the power lost, but I would think that a compression check would be in order to find out what the engine is doing.

I have and still occasionally drive a 2000 E250 with 5.4, 272K on the clock---its far from being tired or unable to hold 70 MPH if needed---A/C on at that. In fact I bought the van with 203K so at 215K if its been regularly maintained its far from being over the hill, pun intended. :)

As to Jazztone's issue----does the engine RPM increase as though the trans is slipping? If so I'd find a better trans shop, not necessarily the one with the biggest advertising budget or cleanest waiting room---someone who knows their doo-doo.

We run a fleet of fords and have over a dozen with the 5.4 we get over 200,000 Strong runner, something is going on here, do you feel the transmission down shifting as the truck slows down? when your losing power is the engine revving up? Get on a back road and from a stand still floor it, make sure she goes through all the gears and you feel the shifts, let us know

It goes through all the gears. If I WOT is when I lose production. If I baby it no problem.

Then the transmission is not slipping.

My guess is that you have a fuel delivery issue. It could be a weak pump, or a plugged filter.

New pump and new filter. Do you think the new pump may be defective?

Maybe get a scan tool and check the fuel trim data under at least 3 different driving conditions idle, 1500 rpm and something in the rpm range you are having the issue in. MAF sensors will cause drivabilty issues like you are experiencing, MAF sensors can fail subtly and not in a linear manner that will set a code. If the truck is returnless fuel system design it will also have an FPDM. That controls fuel pump duty cycle. The FPDM is tough to trouble shoot with out more tools and service info. Let us know how it turns out. Take care.

New MAF sensor. I don't have to testing equipment. Can I rent equipment capable of these reading?

No place I know of has them to rent.....maybe hit an advance auto and take one of the "parts experts" for a test drive:-jammin

Been there and done that. Local shops are scratching their heads too. I shudder at the thought of going to the dealership and they are saying 2 weeks to get me an appointment. I am trying not to dump the van as it has been so reliable.

If you take into account the money you've spent on parts and repairs a scan tool is pretty cheap....check out a couple of the units at harbor freight. The unit has to have live data. Back to basics....can you pull at least 1 plug from both cylinder banks?