Hi Guys,
Well the problem has come back. I replaced the exhoust and left the battery unhooked for about 3 hours. The truck ran great for about 700 miles then started losing power again. It seems like it goes into limp mode and if I try and floor it it even losses more power. If I slowly increase throttle it climbs to about 50mph and I can limp home. I pulled the codes and got 111 (twice) then 6 seconds and got a 172 (twice). With engine running I get a 632 code.
By these it would mean that the O2 sensor is gone as well as the transmission control switch could be going. What I don't get is why the truck would work fine for several hundred miles then just seem to shut down. If I leave it for a while (sometimes just 10 minutes) it is fine again, if a sensor is gone it should be acting up all the time. It is a 1986 E350 with a 7.5 litre engine. I see that several others have had simalar problems however I have never seen anyone come back with what the eventualy found. Any info thanks

 

Okay, when was the last time you tuned it up? I mean the whole works. Motorcraft plugs, NAPA's BEST wires or dealer wires, new cap, and rotor again use dealer parts or NAPA's best. THey will cost a lot but the igntion system can make or brake a vehicle, pay a lot now or pay more getting it towed. Then replace the O2 sensor again. How many miles? It's gotta be a '96 to have 3 digit codes, not an '86... Take it and have the injectors cleaned too.. YOu might try SEAFOAM.

 

Right 96 not 86 (lack of sleep) new plugs, wires,roter etc. in October. Will replace O2 sensor and see what happens next. Just seems strange that it works for several days fine or on a long trip then suddenly fail. If I leave it for as little as ten minutes it is fine again.
Thanks for the ideas.

 

hello, fordfuelinjection.com code list says "111" system pass. "172" running lean right side" but shows that code as "keor". "keor" for 632 says "overdrive not cancelling"
when u get it up to 55 does it run smoother? maybe it's stuck in overdrive?
is it farting under load like a misfire? if so run it at night and look for sparks from bad wires or crossfire.
your o2 sensor might be ok if the codes weren't cleared out, but if you hade a manifold leak it would make the engine run rich and the sensor might have some of that black smoke on it.

 

Yes when problem occurs it does sometimes sputter and backfire a couple times. Could be a manifold leak and is drawing in air upsetting O2 sensor every now and then, will check bolts again. Just seems strange that it works for several hundred miles (or days) then craps out. It has about 170,000 kms on it so O2 sensor is probably shot (I bought used so don't know if changed prior). New fuel pump and filter in fall.

 

the o2 is cheap even with the tool. i'd do it first. that tranny code doesn't sound right. you didn't get ground codes but i'd check the battery term. follow the wires abit. make sure your air filter is good!.
the last thing i'd check to see if the cats are clogged. when an engine won't speed up when hot it's often the prob. good luck.

 

I think I got the tranny code because I forgot to cancell the O/D prior to dumping codes. I don't have cat (was gone when I bought van) I replaced the exhaust with 3 inch from front to rear. Am going to pick up sensor and another new rotor on way home today as quick possible fix, will also retorque manifold bolts to ensure no leaks to O2 sensor creating problems.

 

The no cat may be upsetting it some.. It can cause the air to flow too fast for the sensor to get and accurate reading. The 3" system may have something to do with it too...

 

i was waiting for pfogle to get back to you. i remember him telling someone that 3 inch pipes shouldn't be used. backfire? not cool. more info please. what brand of tune-up parts?. did you have this prob. before the tune-up or pipe change?. these vans get hot in the compartment and are prone to crossfire. best napa or motorcraft only, you can gettem online.
check all of your vacuum lines, this can case your trouble.. as the weather warms up a leak maybe expanding. when you replace the rotor, check the dizzy for anything loose.
any info of when this started and any other troubles you've repaired.

 

Okay, changed O2 sensor, dist cap, rotor, plugs and wires (used bosch parts) and fuel and air filters, cleaned the throttle body and area as well as treated the fuel. Had battery unhooked for the two hours it took and then went for drive. Over the couse of the 150-200 miles it worked okay at varying speeds, however when I stomp on it it still seems to rev and not go. I can feel it kick down but it dosn't seem to engage. Also at about 50-60 mph it constantly shifts if I am in O/D, coulkd be that it is a big truck (18 ft cube van) and that is the power band. I didn't get any codes but then again after I changed out the exhaust it went about 500 miles then started. Will let you know if anything comes back. Sure hope it isn't the tranny packing in but that is what it feels like as if it is running through sand and can't seem to keep going. The problem started last Dec, temp outside about -30 at the time. I noticed that not much pressure at exhaust at time and figuresd it may be pluged, before I could get around to fixing it (it would go away for a few hundered miles) the muffler blew out and the problem didn't come back for as couple months (lived with noise ratther than change exhaust outside at -40). Then end of March it started lossing power again so I thought maybe a plugged CAT (as did some of you) that is when I discovered that the previous owner had removed the cat and was running 3 inch to the muffle and back. I replaced the muffler and pipe as req. and problem was gone for about 700 miles then it came back for a day then good for a couple hundred miles. So now that I have changed most of the probable problem parts will see how it goes.

 

sorry to tell you this but i swiped this next part from a post today. you have a odb2 system. your last muffler may have blown up. the comp. is sensing running lean and probably is causing your trouble."backfires" ect. check this post about running no cats. "Why would you really want to run without one. There are good affordable high flow converters available. IF you have OBD II, you cannot run without it. You will have a check engine light, and the computer will attempt to lean out the engine to help reduce emmisions without a working cat. This can damage the engine. Also, if you have a check engine light on, regardless of your areas emmisions policies, you will fail the safety inspection."

 

Well it's back again, made about 1200 miles this time. Was driving along about 40mph and could just sense that the power was gone. Stepped on pedel and nothing, just bogged down and sputtered as bit, eased off pedal and applied it slowly (letting engine gain speed as it liked) and drove fine to next strop on route. No check light just lack of power. Shut truck down for the 10 or so minutes I was there then started right up and worked fine for the next hour and a half of around city driving. Then on way home felt it do it again, as long as I didn't stomp on gas it would pull fine, after I got on hwy and had to speed up to 60 it would only get to about 50 or so. I applied more pedal and it bogged down and then check engine lite came on and went off about tewn seconds later. Five miles later it came back on then went off again (happened three times) about 10 more miles down road light came on and stayed on. Engine would still work okay as long as I didn't stomp on it. Will pull codes again tonight and let you know what I get.
While I agree that running a CAT does not hurt anything I don't see why it would suddenly start this after more than a year of not having one. Also I only had one O2 sensor in the system down where a cat would go. On a 1996 7.5 how many should there be, I wonder what other mods were done prior to my owning it.
Thanks

 

Okay... It sounds like you are having a fuel delivery issue. Have you checked the fuel pressure? Maybe a clogged filter? I would check the harness on the top of the tank, and make sure the grounds are in good shape.. Then I would check the pressure. A failing pump or regulator can cause odd things to happen.

 

Okay,
Dumped codes last night and got a O2 sensor and a 632 Trans Control Switch. I dumped them and drove for about 45 min then checked them again, no codes with KOEO so no O2 problem and still got the 632 Tranny code. Just to make sure I dumped them again and ran it for a while and retested this time I didn't turn wheel or things and got no codes for engine off and got the tranny one as well as two operator error so I guess codes are working. I agree it could be a ffuel problem, where is the regulator located, I had a new pupm installed last August and replaced the filter last week (again). Will check the wiring and such tonight and see if our local parts place lends out pressure testors.
Thanks

 

THe Tranny code is because you didn't cycle the O/D switch when pulling the codes. That is all that is... So it's not a problem. Pull the engine cover off from the inside, there will be a round silver object attatched to the fuel rail that has a vacuum line on it. Check the fuel pressure with the key on and engine off. It should stay around 45psi. Then start the engine and it should drop to between 35 and 40psi. If it stays high the regulator is bad, or the pump was the wrong one. If it falls then the pump is not keeping up.