Hi All - I had a problem with my truck( in my sig) on the way to work today but I made it here and now I'm concerned I might not make it home. I have a 95 F250 7.3l w/ 202k and an E4OD. I haven't had a problem with my truck and been driving it lately on weekends pulling my 18' enclosed trailer, last year it was my daily. Today I decided to take the truck to work ad was sitting in stop/go traffic. I noticed my check engine light (CEL) coming on and off every now and again but nothing was off about the truck. Once traffic picked up the pace I was noticing harder than normal shifts between I think 2nd and 3rd but I wasn't paying attention, I know I was going between 20-35 though. Suddenly I got a loss of power and experienced only what I can describe as a shudder when on the gas until I let off and slowed down to around 10-15mph. If i didnt slow down and kept on it once I got up to 40ish and the trans shifted then it would go away along with the CEL. When costing if it would downshift the CEL would come back on the second I gave it minor throttle and same thing would happen. If I got all the way down to under 10 the CEL would turn off and no issue. What's weird though is if rather than slowly rolling up to speed if I was a little heavier on the pedal as if I had my trailer attached then I never experience any of these symptoms, its only at lower speeds or trying to ease into throttle.

I verified this on the off ramp when coasting to a yield I had this "shudder" from 10mph - 30mph, when I got to a stop light I was heavier on my throttle and had no issues all the way through the range. I did notice a few times in the last year where I would get a CEL after a hard shift from 2-3, this only happened maybe twice last year. I have noticed when merging onto the highway though that the truck tends to shift hard into 4th after hanging for what feels like a second or two too long.

Important notes - When I rebuild the truck I pulled the pan and replaced it with a Maghytec, new deep filter and replaced the fluid w/ Royal purple ATF. I also ran a remote trans cooler back under the truck bed w/ an electric fan attached and have a trans temp gauge. I haven't ever seen the trans get over 180* so far since I've installed it which was before I daily drove it last year. Hoping that fluid was ok, I was very thorough when I did all this so I'm sure I researched the fluid first but please let me know if I made a whoopsie.

Apologies if this has been covered, I tried looking this up in search and google but haven't found anything that seems close to this. Appreciate any help!

 

The ONLY way to know what's wrong is to read the codes. The check engine light means there are codes stored to tell you what's wrong. Without the codes, all anyone can tell you is that something is wrong.

You should have read the codes when the check engine light first came on. Now that there are more symptoms there are more things wrong. You might have been able to prevent the additional problems by taking care of this when it first happened.

Here is how to read the codes: www.troublecodes.net/ford

 

Thanks Mark, I did try reading the codes way back but I have a 95 with an OBD2 and my scanner doesn't work so I couldn't pull anything. I'm use to following the method via your link from my old 95 F150 that had an OBD1 port, is there another way to check the codes or activate the OBD2 port?

 

I've never seen a 1995 truck with an OBDII port. I have no idea how to make that work.

 

Well I figured it out after googling it this afternoon, apparently FORscan works on these trucks and I happened to get it for my Bronco to change some settings and gave it a shot and it worked. My other scanner I used last year apparently doesn't work on this era of trucks w/ the 7.3l, I got the below codes:

P0607 - Power Interrupt on KAPWR
P0344 - Camshaft Position Sensor A Circuit Intermittent (Bank 1 single sensor)
P0470 - Exhaust Back Pressure sensor circuit malfunction

I'll start with cleaning out the EBP tube and inspecting it to see if it has any issues and go from there before I get new sensors.

 

...Delete...

 

Gotta love FORScan!

 

Right! best $12 I've spent in a while, I didn't even know at the time it would work on my truck. I just wanted to unlock my Bronco's GOAT modes and disable that damn double honk lol. I'll report back what ends up fixing my issue here once I do some more troubleshooting and maybe some new sensors.

 

Just wanted to throw out an update, I decided to start with the CPS and replaced it since it was cheap and somewhat common so I did that today since I finally had time. I pulled the old black sensor out and replaced it with a new gray one. I took it for a 2 mile trip down to the convivence store and back and it ran great except I kept getting a CEL when letting off the gas and heard a ticking from under the hood. Once the RPM got to idle range it would go away but I had no power issues. Unfortunately on my way back though the same symptoms presented themselves so I limped home and once I put the truck in park it stalled which was new and I assumed might be related to the CPS? I'll start next with the EBP sensor and tube but in the mean time if anyone has any other suggestions or sensors I should check while I'm in there I'm all ears.

If I start the truck it will stall reliably after about 15-20 seconds but after some research that may be because I had my computer plugged into the OBDII port?

 

Just figured I'd update again, I was on travel for the week and got home this morning so I decided to take a look at the truck. I pulled the EBP sensor and it wasn't plugged but I cleaned it anyway decided to pull the tube and found that it was rotted off at the manifold so... it hasn't been connected for some time likely since I've owned the truck. I hooked up ForScan and got the same three codes again. I'm assuming that the EBP sensor is bad considering I've replaced the CPS (new one could also be bad) and the tube has been rotted for some time. I'll go for an EBP sensor to see if that resolved the issue. All my connectors and pins look good on both sensors so logically the EBP makes the most sense to me. I'll likely make an attempt at replacing the tube but when I went to remove it at the manifold the fitting broke off leaving the threads inside so I'll have to deal with that I'm mainly curious if a new EBP sensor will fix the issue since the tube has been broken for a while and I never knew and the truck ran fine.

 

I'm wondering if the CPS(gray) is wrong, onw, now that it stalls, any way to check the sensor, does your speedo bounce. Diesel OBS's are totally different animals, when checking for codes compaired to regular OBD I trucks,
I'd ask same question here-->1994.5 - 1997 7.3L Power Stroke Diesel - Ford Truck Enthusiasts Forums

 

I verified that the OBDII scanner was cutting the motor it doesn't stall without it hooked up and everything is the same. My speedo doesn't normally bounce but if i recall right it did when i was on the freeway the first time it happened and it only bounced while the rough idle/loss of power is occurring. I took a quick video because I can get it to happen by revving the engine, I may throw it up on the PSD section as well TY.