Any Powerstroke Guru's on here?

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cjnspecial

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Truck is a early 99(3/98) F350 crew cab with no mods.

I've brought my truck to 2 powerstroke mechanincs that seem to have caused more problems. To give you an idea of what's going on, the GEM was bad so I replaced it and it had the computer/
GEM, etc reflashed to the the most recent software and not only did it not fix the problems I had, it created a new one:
1. *Torque converter won't unlock from overdrive until downshift.
2. *Windshield wipers and radio still work with key turned off.
3. Engine has no power. I can unplug the map sensor and it runs a lot better but still doesn't make the same power as it used to. I swapped the map sensor with a known good one and it still ran like crap.

* These issues were present before the GEM was replaced.

Truck is a early 99(3/98) F350 crew cab with no mods.
 
What are you calling the GEM? The best thing to do would be to go to ford and have them reflash it once to see what happens.
 
What are you calling the GEM? The best thing to do would be to go to ford and have them reflash it once to see what happens.

GEM=Generic Electric Module. Already went to shop with OEM ford software( VCM IDS) and to ford dealer. Their techs only know how to plug in the computer and replace part that computer says but didn't seem to be real versed in powerstrokes. Someone that really knows what they are doing can read all the inputs and see what's going on. I have Alldata but all the sensor data is propritary or I would track it down with my multimeter.
 
Truck is a early 99(3/98) F350 crew cab with no mods.

I've brought my truck to 2 powerstroke mechanincs that seem to have caused more problems. To give you an idea of what's going on, the GEM was bad so I replaced it and it had the computer/
GEM, etc reflashed to the the most recent software and not only did it not fix the problems I had, it created a new one:
1. *Torque converter won't unlock from overdrive until downshift.
2. *Windshield wipers and radio still work with key turned off.
3. Engine has no power. I can unplug the map sensor and it runs a lot better but still doesn't make the same power as it used to. I swapped the map sensor with a known good one and it still ran like crap.

* These issues were present before the GEM was replaced.

Truck is a early 99(3/98) F350 crew cab with no mods.

My 01 f-250 radio and door locks work for bout 5 minutes after the key is turned off as long as the doors aint opened. Its supposed to do that, or mine has since new. Torque converter aint sure about. Seems like mine doesnt unlock until down shift either. Actually i think the first downshift is the converter unlocking. Have you changed the fuel filter. Thats usually the number 1 thing for less power, expecially on a diesel. Hope i helped a little
 
My 01 f-250 radio and door locks work for bout 5 minutes after the key is turned off as long as the doors aint opened. Its supposed to do that, or mine has since new. Torque converter aint sure about. Seems like mine doesnt unlock until down shift either. Actually i think the first downshift is the converter unlocking. Have you changed the fuel filter. Thats usually the number 1 thing for less power, expecially on a diesel. Hope i helped a little

Mine will stay on overnight. I've left the radio on overnight several times...good thing it's got 2 batteries, lol. The fuel filter only has about 15 thousand miles on it so it should be okay.
 
Mine will stay on overnight. I've left the radio on overnight several times...good thing it's got 2 batteries, lol. The fuel filter only has about 15 thousand miles on it so it should be okay.

WHAT???

It could very well be the fuel filter in 50 miles.. A cheap fix. If it may not be the filter, then keep the old one. Then you are out nothing. I have had fuel lines go bad on the inside and plug a filter FAST.

I think there are two types of systems, some filter all the fuel, and some filter only what is being burned.

Good Luck.

Now if you know why the electric 4x4 needs resetting all the time, Lemme know.
 
Dp tuner might be able to help you. dp-tuner.com is their website. He does custom tuning on a lot of trucks. The fuel filter might be clogged. I would change it as to eliminate it.
 
After just coming out of winter, I would be changing the fuel filter, more potential for water being in the fuel, you never know when you get dirty fuel.
I've went 30k miles and I've went 5k before changing a filter. Sounds like you need to find another dealer or a shop that specializes in diesels.
 
Mine will stay on overnight. I've left the radio on overnight several times...good thing it's got 2 batteries, lol. The fuel filter only has about 15 thousand miles on it so it should be okay.

The power issue may be in the tuning, since it happened after the computer reflash. The injector timing may be off(computer controled) Does it still start fine?
 
I don't think it's the filter because it runs decent with the MAP sensor unplugged. If it was the filter, it would run like crap with the map sensor plugged in or unplugged. It's almost like the the ECM isn't reading the map sensor readings correctly. Maybe they programmed my truck to 99.5 specs instead of early 99 specs...seems like they are different.
 
There were a few differences in the 99 to 99.5. The turbo compressor wheel is different. I don't know if the programming would change much as they were rated at the same power. I think who ever did the flash messed something up.
 
I have completely gone thru the entire fuel system. I know it intimately.

Rather easy to fix once you understand it.

PS My truck didn't seem to run at the 'dealer recommended' 50 - 55 pounds fuel cap pressure. Runs fine at 70.
 
You can get a plugged filter w/ one tank of bad fuel, but I think it was in the re-flash. I learned long ago, if the truck is running fine, do not let a dealer re-flash it. It usually causes more problems than you originally had. Here is another good source of info for diesels.

http://www.thedieselgarage.com/forums/
 
I'm not a guru but I have worked on lots of powerstrokes. There are 2 computers that control a PS, the ECM and the IDM (injector drive module) and as far as I know the GEM controls door locks, cruise control, etc. but has nothing to do with the way the engine runs. How much oil pressure is the high pressure oil pump putting out at idle? Are there any engine codes stored in the ECM? What is the reading from the EBP (exhaust back pressure) sensor? What is the reading of the MAP sensor relative to the BARO sensor?
 
The first thing that I'd do is change the oil. If the anti-foaming agents break down a PS may run like crap or die. If you had a way to check ICP pressure at idle and under load that would tell you quite a bit. It'd also be nice to see what the IPR is doing under load.

Have you checked your battery saver relay? Try swapping it with another.

The 4R100 trans should lock up in 3rd gear and remain locked up until a downshift to 3rd. If it really is staying locked up then the TCC solenoid or valve are likely culprits. The 4R100 has a nasty reputation of sending debris into the valvebody where it wreaks havoc.
 
Ford Truck Enthusiast is another good forum.

I had a problem with my Powerstroke and the dealer couldn't figure it out.
Somebody on that forum told me what the problem was and the Ford part numbers to fix it. I told the dealer and they replaced the parts. Fixed it under warranty.
 
There is a lot of VERY good dealer techs out there. Most dealers just don't have enough diesel traffic to get good at diag.

I understand why a lot of dealers and their techs get a bad rap. Many are just lazy. As a former Ford dealer tech, now Honda, I've never met a tech in the aftermarket that seemed to be anything worthwhile. It goes both ways.
 

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