First off, new to the board, so thank you in advance to everyone who can provide some input. Sorry if it is a little long but I want to provide all relevant info.

The vehicle: 97 F250 HD w/ 7.3 PSD and auto trans. ~213,000 miles

I have owned it about 4 months. Since then I had problems with it randomly dying and first had the CPS replaced. This did not fix the problem and after further diagnosis Ford found that I had an old chip installed that had corroded and was most likely the culprit. They removed it and that problem seems to have gone away, but now there is a new problem.

The truck starts up fine, idles nicely, and even drives fine when I first pull out of my driveway. However, every time since I got it back from the last repair, some time in the first mile or so of driving and usually from a stop, it completely loses throttle response. This has happened 4 times.

1st time: I was towing my trailer. Came to the light in my neighborhood. Stopped. Then the light turned green and I went to accelerate and it would not rev over 1000 rpm. It's like it was limited to that no matter how much throttle i gave it and felt almost like my trailer was dragging me back. I limped across the intersection, pulled over, got out and looked over everything. Everything seemed fine, so I got back in and then it drove fine the rest of the day.

2nd time: No trailer this time. It started up fine, I drove about 1/8 of a mile. Stopped before making a turn and then the same thing, but this time at about 1400 rpm. I tried flooring it and still no change. I pulled over and the RPM surged up and down for a few seconds and then it died. I was able to start it up after that and it ran fine again.

3rd time: Similar to 2nd time, but that time when I pulled over it idled fine and after I waited 30 seconds or so it drove fine.

4th time: It had been sitting for about 6 hours after I drove it. It started fine, and I got about a mile. This time, I was driving about 25 mph and then I lost power and started slowing and when I hit the accelerator I again could only get a steady 1400 rpm . I pulled off, waited a few seconds, and drove 30 miles home with no more problems.

These occurrences were all sequential, meaning I have driven it 4 times since I got it back from ford and had this problem every time. It should also be noted that if I stop for gas or any other small amount of time and the engine is still warm, the problems did not come back when I started it up.

I got tired of having to deal with it and haven't had time to mess with it for about 6 weeks now. I went out the other day to check the fluids etc., and found that the oil was very low (not even registering on the dipstick) and that the tranny fluid seemed to be a bit overfilled. This is strange because I had Ford check all of the fluids and they said they were all fine. Plus, the truck does not leak a drop of oil and does not appear to be burning any as I do not have smoky exhaust at all. Perhaps the tranny fluid level adjusts after starting the car and shifting from park. It is an auto trans. w/ approx. 50k since rebuild.

Any ideas and thoughts are greatly appreciated. I'm thinking it is a fuel delivery issue, perhaps even just a clogged filter or screen. This is my first diesel though so there is a bit of a learning curve. I'm planning on taking it back to the dealership either Thursday or Friday but was hoping to have some ideas of the problem when I went in. Or who knows, maybe it is something simple enough for me to fix.

Thanks

Jake

 

If you don't have a code reader it may be beneficial to find one to use and at least check if you have some codes stored.

I'd pull your fuel filter and see there is a small screen on the drivers side down a little bit. Take a qtip with the cotton removed and clean the screen off. Check your fuel pressure. There is a schrader valve on drivers side fuel regulator area to put a tire guage on. It should read at least 45 lbs.

Your tranny fluid will go down when the truck starts. How old is the oil? I'd also change the oil and make sure its full.

Don't throw out the idea that the cps is bad already. Does the tach move when trying to start it? Sometimes these cps's last a day or a few years. Seems to be the luck of the draw. I'd get a new one and try it, you need to have a spare anyway. I run the light gray one from ford, but heard the dark gray from international is the way to go now. I just had to change mine out again and gonna get a dark gray one next.

I'm not a genius with these trucks for sure. These are just some basic easy things to check to start with. Hopefully someone smarter will help you out some more.

BTW welcome to FTE
Good Luck

 

There are a couple of symptoms that you have mentioned that were similiar to mine. I had a ICP that was shorted out and actually burnt out the VRef circuit in the PCM. But, the symptoms are very similiar to yours. I would maybe check the ICP sensor and see what may be found there. Use the reference below to check it out. Hope this helps.

https://www.ford-trucks.com/forums/9...dea-again.html

 

Jake, as far as the power loss I would try unplugging the EBPV (exhaust back pressure valve). It is a valve located just after the turbo and closes to help the engine heat up quicker. It also has a habit of coming on when you don't want it to. Your old chip could of disabled it. There is a two wire plug located just in front and below the turbo. UN-plug it and see if the issue goes away. It won't hurt anything and many of us just disconnect and forget it.

As far as the oil goes if you have never changed it this would be a good time. It takes 14 quarts with filter.

You can easily do these thing and possibly avoid a big service bill.

 

Thanks for the advice so far. I decided just to top off the oil so I got a gallon and put it in. Turns out I am still about 3 quarts short. Hopefully I didn't F up my engine by running so low on oil, but my temp and OP gauges have been reading normal. Right now I'm trying to figure out where the oil went since there are no leaks and it was supposedly full about 500 miles ago.

I bought a fuel filter to replace the old one, but am not 100% sure on the procedure here. I found a video for like a 2000 model, but it seems slightly different. I tried searching but came up empty.

So if anyone could point me in the direction of a good write up, hopefully with pictures or a video, I will get the fuel filter replaced today.

I also unplugged the EBPV. Can I just leave it hanging there?

Lastly, on the CPS, if my tach goes to about 200 rpm and stays there while cranking, is my CPS bad. I read that it is supposed to bounce. Mine moves up, but just stays at 200 rpm until it starts (usually takes about 5 seconds and then idles smoothly at ~750-800 RPM).

Thanks again. I am trying to work on it today or tomorrow, so any and all input is appreciated.

Jake

 

Also, I just noticed something else. I turned the engine on and let it run for about a minute. When I turned it off, there was a hissing noise like air escaping coming from the rear of the engine (towards firewall) on the passenger side. Couldn't narrow it down any further. It hissed and then slowed and stopped after about 30 seconds. Tried plugging the ebpv back in and got the same result. Not sure if this is new, or if it was doing it before but I jsut noticed it in any case.

I'm going to buy some more oil now so if anyone has any other input or a link to instructions on fuel filter change I would really appreciate it.

Thanks

Jake

 

Your engine that low on oil can be why it quit. These motors from what I understand are designed to shut down if low on oil to prevent damage.

You can leave the ebpv unplugged, it won't hurt anything.

The fuel filter is right on top in the middle of the motor. There is a little yellow plastic lever on the pass. side, turn it 90 degrees and it will drain the bowl. If you run a hose down it won't make a mess, I just let it drain out in the gravel. Sometimes you need to get the cap loose to relieve the pressure.It has about a 4" round black plastic cap on it. if you still have the engine cover on its right under the lid. Take the cover off if you have it and probably need a screwdriver to lay in the lid to get it loose. Pull the old filter out, the little hole with the screen is on the drivers side right close to top, clean that. Then just put back together. The filter may pull out a little hard, just pull straight up. If you fill the canister up with fuel it will start faster.

Your oil down that far is really probably it. You need to figure out where that's going if it was full 500 miles ago.

 

Hissing is probably some vacuum hose leaking. There is one that runs across in that area that supplies vacuum to heater/ac unit.

Yes, you can just leave the EBPV plug disconnected.

That is a lot of oil your missing. Hopefully last owner just did not put enough in or did poor maintenance. The only other place it could go would be the fuel tank. If the injector o-rings are bad then high pressure oil can mix with the fuel. When you change the filter look at the fuel in the bowl and see if it is oily-black look.

 

UPDATE: I pulled the old fuel filter and everything looked fine, at first.

The filter itself was quite dirty, and BLACK. The fuel in the bowl looked fine. In fact I took some out and held it to the light and it looked perfectly clean. So I drained the fuel from the bowl and then I saw the bottom of the bowl. Under the base plate that the filter sits on I could see black sludge. So I got a q-tip and swabbed some of it and it appears that there is a decent layer of black grimy oily sludge at the bottom of my fuel bowl. This was probably mixed in the fuel when I was driving the truck, but since I have not driven it in 4-6 weeks has since settled to the bottom.

I then checked the screen. Quick question on this. Is the screen out of view inside the side "tube" I guess you would call it, or is it supposed to be visible on the wall of the fuel bowl? In any case, I swabbed around inside the tube and found the same black gunk, just less of it.

I can only imagine this is oil in the fuel, and would be where my oil has been disappearing to. I just went and checked my service records and according to Ford I was only ~2 quarts low 300 miles ago. Today I was approx. 7 quarts low. I imagine this means very leaky injector o-rings? Is this the only potential cause, or could there be others.

Lastly, is this likely to have caused the symptoms I was explaining earlier of the engine not revving when cold and then working after waiting a short period of time, or have I just uncovered more problems?

Oh, also, how can I clean the gunk out of the bottom of the fuel bowl? Can I like open the drain and run some water through it or what? I can't seem to get a rag under the base plate for the filter to wipe it out.

I can also get pictures of everything I'm talking about if I have not been clear enough.

Thanks again. I look forward to any input it the morning.

 

Jake-welcome to the board. This is sounding like you need injector O-rings. These injectors use hi pressure oil in a gallery in the heads right above the ful gallery. The oil passage and the fuel passage are separated by an o-ring at each injector. Take your time and do your research and then decide if you wannt to do it yourself or let a shop do it. If you want to do it yourself, these guys will keep you pointed in the right direction

 

Thanks. I thought that was the case. Doing the o-rings is probably more work than I am up to, and unfortunately more expensive than I would like to pay, but I will most likely have the dealership do it.

Another question for you all. Are there any other repercussions that can come from having my oil run so low, or should I be fine if I fix the problem now?

 

IMHO I think it's gonna be fine once you get past this bump in da road. See if the dealer tech. will let you hangout and learn while they're working on your truck. If it were me, I would at least want to witness when it gets startedthe first time after this job.Things get a lot less intimidating to me once I've seen it but since I'm too much of a cheapskate to give them those labor $'s I usually do my homework and work slowly and a little scared. Then when I get it right I win big. good luck

 

Just another thought I had. I have read that bad injector o-rings will give you a lot of smoke on start-up. I have almost no smoke on start-up, or ever really, at least that I have noticed.

 

Any chance this could be related to TPS or AP sensor?