2001 Ford E250 - won’t go above 45 mph!

I have a 2001 Ford E-250. Please forgive the length of this. I have done a lot of research trying to figure this out and need to figure out what to look at next and can I (w/sons’ and husband’s help!) DIY it somehow?

Car was running terribly about 3 weeks ago. I ran the codes, based on those, I thought it was maybe an o2 seonsor - I had already replaced B2 S1 but figured maybe B1 S1 needed replacing too. When it would not go over 25 mph I paid a shop $100 to give their diagnosis: they said the o2 sensors were done but it was the DPFE sensor and it’s vacuum tubes, and that we have a couple of bolts broken off in the passenger side exhaust manifold.

Replaced the DPFE Sensor and hoses myself, have to save up to pay the shop for the manifold. Car still running hard to go over 30 mph. NEXT day, heading out on a trip, so not close to home, listened as some kind of back pressure blew the two vacuum tubes back off on the DPFE, and we continued the 8 hour trip at an agonizing 40 mph (it was able to go a tad faster W/O the DPFE tubes in Place!)

To try to test the Cats, I removed the one B2S1 O2 sensor I had replaced already and tried to drive it. Drove better- still took some time to get to 50, but still got there after about ¾ of a block. But could visibly watch the exhaust entering my cabin- not teneble to leave it out and drive it that way! Another few days of poking about and researching later, pulled the codes today: P0135, P0155, P0402 P1406, P1131, P1132, P1152, P0171, and P0174.

Running rich, running lean, not functioning at all (that is the one I replaced, removed, and put back in.) EGR Valve Pintle stuck. So! Never any codes about the cats or the DPFE sensor. But the EGR has come up twice. Pro shop said NOTHING about the EGR before even though the P0402 was there at that time too. So - should my next step be to try to clean carbon from the EGR pintle? Clean the MAF sensor (I’ve read that can be a cause to all this too), or work with the Cats?

And if we can go most important but still most economical to start I would be grateful. I can do a certain amount on my own but am on truly limited funds and have a family of 9 to drive around! Thanks.

Try replacing the flow control orifice pipe of the EGR circuit.

Tester

An exhaust restriction can cause EGR system faults, seems to be a common misdiagnoses. Connect a vacuum gauge to the engine, operate the engine at 2500 RPMs in park, if the vacuum drops to a low value there is an exhaust restriction. You may need to replace the front Y-pipe/catalytic converter assembly.

Van shifts at normal rpm? 2k or so? What happens if you drive in 2nd gear to try and rev motor higher than 2500 rpm? Does motor bog down?

It almost seems like it’s in 2nd most of the time because of the way it runs. It’s not but just seems that way. Going to first or 2nd definitely makes it even harder to get speed (as would be expected).

I have spent about 2 hours searching and see tons of info on how to clean the EGR for insufficient flow and nothing on what to do for excessive flow or how to clean or replacement the flow control orifice - but seeing as something threw the pros off the scent of the EGR and onto the DPFE AND one of the two vacuum tubes blew off - this seems like a reasonable thing to look at. I will keep trying to find how to clean or replace the FCO

No offense, but I really hope it is not that! Haha. All the same I will give it a vacuum test. Thanks

I tend to think an exhaust restriction.

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V6 or v8 motor

I think is a V8

I have spent the afternoon trying to get the EGR valve off so I can clean it and darned if this bolt to the flow orifice control will not move (on round 3 or 4 of PB Blaster now. Good grief! This thing is a monster!

:thinking:……………………

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I think it’s a 4.2 v6 or 5.4 v8. I assume the v8 would say triton on the fender side? Seems to me a failed cat results in performance slowing dropping vs all at once like a failed part?

I should have said it IS a V8. I was trying to get my 10 symbols in to answer haha. Anyway - we have actually had the car for only about W months and thought it was a vacuum leak in the beginning, but had one shop tell us the hoses all looked fine and that the O2 sensor was likely the cultprit instead. And thus began the journey/saga I relayed in my OP. So to answer this question… maybe performance was slowing even before we got it and I was not aware of how long the problem had been preexisting. He said it had pulled the codes (for O2 sensors, which he suggested Might be the vacuum leak) just the day before we got it and lowered the cost for us to repair a possible vacuum leak.

Got the EGR Valve off today, sprayed it out really Well with Carb cleaner and let it sit a bit and put it back on. I was unsure about putting the carb cleaner into the Flow control Orifice with the engine cold, and also no way to drain it out so I left that as-is for now. Reattached the one blown off DPFE sensor vacuum tube, and went for a test drive.

It ran a little better - with no stutter on a cold acceleration. And was a tad quieter. The vacuum tune on the DPFE remained ion, so far. Acceleration was still a little on the slow side but I have not run it on the freeway at 50+ yet. Will do that tomorrow when I have the doghouse back on. Appreciate you all giving input - I really was running into a series of brick walls and your advice is giving me new avenues to explore. Thank you.

I have yet to see any codes suggesting the Cats, DPFE, or the like. The EGR has Come up twice though so I hope this is it. In looking at it, I am not sure I am equipped to replace the Flow Control Orifice tubeon my own. It is in a very tight space and would require taking off much more than I am sure I can reassemble. But I am open to the suggestion that that needs to be the next step.

Update to say that it still takes about a full block to increase speed by about 10 mph, and once t hits 45 it wants to go to a lower gear and will not go any faster. Even under protest. The only
Time in the last week that has been different was when I drove it with one of the O2 sensors taken our completely. I am at a loss on where to look next.

I must say . . . based on everything I’ve read so far, I don’t think your shop(s) are using sound diagnostic methods

It sounds like your exhaust is restricted . . . I’m in agreement with @ok4450

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M[quote=“db4690, post:16, topic:122240, full:true”]
I must say . . . based on everything I’ve read so far, I don’t think your shop(s) are using sound diagnostic methods

It sounds like your exhaust is restricted . . . I’m in agreement with @ok4450
[/quote]

I am thinking that shop messed up the diagnostic too. So what kind of things would bring on an exhaust restriction? Cats?

On the way home today it would not even go over 35 without real struggle - and no red lights. Almost like the “limp home mode”. It’s like Drive is missing and it wants to stay in 2nd. Could those codes point to something with the transmission fluid or solenoid possibly?

yup

A competent shop should be able to determine if the transmission is indeed in limp home mode. They should also be able to determine what gear is being commanded, what gear it’s actually in, and if the solenoids are doing their job

Part of the big picture includes having a decent scanner, common sense, proper service information, etc. I feel that shop you’re using is lacking one or more of those.

I am going to go back tomorrow to make them do the job properly. I also figured out today that on the gear shift, it is almost as if “Drive” is just missing altogether - P/R/N/2/1.

Just ask them how they determined that there’s no exhaust restriction

If their answer is pretty vague, or if they have to think hard about it, then that may explain a lot about them and their methods