Hi there....My first post and my first older non turbo diesel. I'm hoping you experienced guys can set me straight. When I'm driving on the hwy at 65+ mph and I give it throttle, the truck feels like it up shifts. RPM's go down instead of up. When I let off the throttle, the rpms go back up. So it just feels like its driving at too high an rpm and it also seems to be burning a ton more fuel than when I first bought it. It just bounces back and forth in the rev range while at these speeds and its driving me nuts!

I replaced the TPS already. All I can think of now is maybe the converter but I'm not 100% on how they work? Has anybody else had this problem? Truck only has 62k miles. Also, the ABS light is always on. Local mechanic says the abs goes through a speed module or something and could have something to do with it, but I think if that light wasn't on he would never had said this. Though there seem to be a lot of oddities with these trucks, so who knows. I'm just trying to get this thing to be my dead reliable work truck for years to come and hopefully a decent fuel sipper.

Thanks for reading. Any help would be much appreciated.
Jay

 

welcome to FTE.
if i remember correctly the ABS light being on effects the proper operation of the transmission.
by the light being on, the trans will not have torque converter lockup.
or maybe it is overdrive shift.
i never really messed with the overdrive transmissions.
someone more knowledgeable will be along shortly that will that can help you .

 

Thanks for the reply and the welcome. The ABS light has been on since I bought it and the problem has really just started after its been sitting around over winter. You could be right though. Hopefully others will chime in with some magic answers. Thanks again.

 

you may have better luck with this problem down in the transmission forum: Clutch, Transmission, Differential, Axle & Transfer Case - Ford Truck Enthusiasts Forums
i can move this there if you would like, or you can leave this thread and repost down there also.

 

posted, thanks.

 

The abs light being on has 0 effect on these transmissions.

The 3 major sensors that affect it are the fipl, vas, and Tach.

There's plenty of guys more knowledgeable about these than me but start by pulling the codes.

 

Yeah, the ABS light seemed like a convenient stretch to me. I've never seen any truck where the ABS isn't completely separate. Thanks for the reply. I plan on grabbing a code reader this week and testing each sensor.

 

you can get the DTC's from your 92 with a simple paper clip, test light, or piece of wire.

this site pretty much explains the whole process, and also has a breakdown of what the codes mean: http://www.scribd.com/doc/34996350/F...ocedure#scribd

 

Thanks for the link.

 

UPDATE: Read the codes and got 23 for TPS and 26 for Mass Air. Readjusted TPS and cleared codes before another test drive. not getting any tranny codes. There is obviously no mass air sensor on a 7.3 so not sure why that code would show up. I cleared it and it hasn't come back yet. I'm not able to clear the TPS code so something is still throwing it. Its a brand new TPS, its set to .93.

 

diesel DTC#23: Fuel Injector Pump Lever Sensor Input Is Out Of Self Test Range
diesel DTC#26: Transmission Fluid Temperature Sensor Input Out Of Self Test Range

the DTC interpretations you got were for the gas engines, because SOMEONE gave you the wrong link..

i should have given you this link: Ford EEC-IV/OBD2 OBD Trouble Codes ?

sorry bout that!!

 

That makes sense. Probably should have used our brains and found a better code list, but thanks for the proper link. We swapped out the abs speed sensor on the rear diff and it did nothing. No matter what we've done so far, we can't seem to clear the ABS light or the 23 TPS code. Tried adjusting the TPS from .92 - 1.2. The tranny fluid sensor code has not come back since we cleared it, but the problem still exists so thats a little odd I think. I'll have to check the tach sensor. I assume you meant VSS not VAS Jesse? Thanks guys, looks like I'm not gonna get much help here. Oh, I also found a dinged wire in the steering column for the overdrive. Overdrive button would only work when in park. Figured maybe that was it, but no luck. Plus side is I can actually toggle OD on and off now while I'm actually driving. So, I'm pretty confident the torque converter is the ultimate culprit and its probably electrical and it probably has something to do with speed or throttle. Just not sure what else I can check.

 

i am not that up on the ABS systems on these trucks, i had it disabled on all mine because it never worked properly on the older trucks.
and i only had the 92 for a little over a year before selling it to the daily driver it was assigned to.
is the 92 still the basic RABS only unit on the frame under the driver seat?
it is possible the valve is stuck in a non operational condition, or it may be something as stupid as a shorted sensor wire and the unit is working properly. try disconnecting the sensor wire and see if the light goes out.
i also seem to remember if the RABS unit is not properly bled after doing brake line work the light will stay on.

 

I'll take a look, good tip. The brakes are horribly mushy right now, that was actually our next step. We bled each line yesterday and it didn't help at all. Fluid looks pretty fresh though so maybe what you say makes sense. I also thought about the Tach sensor last night and it doesn't make sense because the tach works fine. My truck isn't stock either, has a new flatbed on it. I saw somewhere that even a shorted out brake light could cause stupid issues with the TC on these things. Flatbed has LED lights, maybe something there? I'm beginning to lose my love for this truck!

 

Found this post. Is this how you disabled the ABS?

So here's the FIRST thing everyone needs to do. Yes, try this BEFORE you change out the MC. Under the drivers side floor board, inside the frame rail is the rear abs contoller/module. Facing the front is a large hex nut. Carefully remove this nut. I used a 1 1/4 inch box end wrench. This may not be the exact size but it is what worked for me. Simply remove the nut and TAKE OUT THE SPRING, caution the nut is under pressure from the sping. No brake fluid will leak out. Then replace the nut. Pump your brakes a few times to compress the controller. That's it. This bypasses the rabs contoller which has failed and is letting brake fluid leak by the seals which causes the brake pedal to fade. No the abs light will not light up on the dash.