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I had another thread going with some of this information in it, but that was more focused on a weird noise I was having, so I wanted to start a new one. I have Torque Pro that I use to monitor everything currently. This is on my 05 F350 6.0 159k miles.
I have been having issues with my turbo/ poor running for quite awhile. A long time back (~18 months?) I started having issues where the VGT would go to 85% while driving. This would only happen after cruising for a long time at a set speed. When it went to 85% I would seem to lose most of my power and I would have to let off the pedal, or hit the brake if using cruise and then reapply throttle. Otherwise if I tried to push through it the truck would start chugging and blow white smoke. As soon as I let off and back on though everything was fine.
Over time this got worse and worse, although I haven't noticed it happen for a few months now. Lately I have been having issues with rough running right at startup and slow turbo response. When trying to drive the truck after first starting it, it will start to chug and blow white smoke and the VGT value stays at 85%. As soon as the VGT comes off of 85% the truck starts to run smoother and the exhaust cleans up. Once the truck warms up a little then it will start to act like a non turbo truck from a stop. Just kinda lugs and blows black smoke. Again, once the VGT comes off of 85% I get my power back and the exhaust clears up and the truck is great.
Fast forward to tonight I finally got the time to pull and clean the turbo after chasing a P0299 code as well as what I have described above. After pulling the turbo and getting it apart I was surprised to not find it very dirty. The unison ring could freely move through about 90% of its sweep, with the fully closed position being where it couldn't reach. After moving it back and forth a few times it started to move very easily. None the less I cleaned everything up so it actuates nice and smooth and put it back together and on the truck. In addition I also put a new VGT solenoid plug on as the old one had one broken tab. I crimped and soldered the connection as per the instructions. Immediately afterwards I started the truck up and I could hear the vanes opening and closing as well as watching the VGT% change on TP. Everything seemed to be working fine as it was moving it from 85% to 14.7% and everywhere in between. After about five minutes however it settled down at 85% again. I took it on a test drive and the turbo now seems slower than ever to move off 85% VGT. As soon as it does though it takes off and runs beautifully. When I got home I pulled codes again and got a P0404. I have pulled and cleaned the EGR valve a couple times, the most recent being early April. Also, as a side note I found my exhaust broke off right in front of the cat.
So I guess I am curious if a bad EGR valve could cause the VGT to be slow to be commanded off of 85%? Or do I need to do a relearn even though the truck seemed to be doing fine right after I first started it again? Should I be looking elsewhere? Its getting to the point where I almost don't trust the truck to get on a highway unless I don't see anyone coming. Any help would be appreciated. Any information I left out, let me know. Im willing to try about anything, just have to come up with the time to do it.
You might have a few issues. If you are running tunes, you need to return to stock and do a turbo relearn. Once the relearn is done properly and the turbo is working as it should, you can load your tunes again. If you can not get it to do a relearn properly, then you may need to trouble shoot a bit deeper. A few things dictate proper turbo function. Map, EBP, MAF, IAT, EGR, Fan clutch etc.
Are you still having the white smoke issue? That would be where I would start. White smoke is either an over fuel condition or coolant. Black smoke is usually turbo related. Pull the EGR valve and clean it, if you have an EGR cooler that is leaking you should be able to see the tell tale signs.
It honestly sounds like you need to do a turbo relearn, If you look in the Tech folder the procedure is in there. Follow it to a T! I had to do it a few times and drive the truck with the stock tune for a few days to make sure I had it right. I was banging my head against the wall, until I got it to relearn right. BTW try unplugging the EBP sensor and see how it runs. It could be a bad sensor, clogged tube or bad pigtail. I chased a similar issue like this before, minus the white smoke.
You might have a few issues. If you are running tunes, you need to return to stock and do a turbo relearn. Once the relearn is done properly and the turbo is working as it should, you can load your tunes again. If you can not get it to do a relearn properly, then you may need to trouble shoot a bit deeper. A few things dictate proper turbo function. Map, EBP, MAF, IAT, EGR, Fan clutch etc.
Are you still having the white smoke issue? That would be where I would start. White smoke is either an over fuel condition or coolant. Black smoke is usually turbo related. Pull the EGR valve and clean it, if you have an EGR cooler that is leaking you should be able to see the tell tale signs.
It honestly sounds like you need to do a turbo relearn, If you look in the Tech folder the procedure is in there. Follow it to a T! I had to do it a few times and drive the truck with the stock tune for a few days to make sure I had it right. I was banging my head against the wall, until I got it to relearn right. BTW try unplugging the EBP sensor and see how it runs. It could be a bad sensor, clogged tube or bad pigtail. I chased a similar issue like this before, minus the white smoke.
Thanks for the reply. I will definitely do the turbo relearn. I have seen the procedure you referenced. I planned on doing it originally but after starting the truck the turbo started hunting which surprised me because it’s never done that before. However, I will relearn it.
I am not running any tunes, all stock, so they are not in the equation.
I still have the white smoke issue when cold. I think it’s an over fuel condition since it clears up when the turbo starts doing it’s thing. Also, no indications of coolant in the EGR last time I was in there. I have pulled and cleaned the EGR twice since I’ve owned the truck, most recently within the past few months. The last time it wasn’t very dirty at all.
I will I’ll also unplug the EBP sensor and see how it does, however I replaced that and cleaned the tube within the past few months as well, same time I cleaned the EGR. Also, it appears to read right when looking at it on TP.
Alright, I finally found some time to try the VGT relearn. I followed the procedure in the tech folder and that got me nothing. While letting the truck idle for five minutes before doing the drive cycle I never heard the turbo change pitch like it was moving the vanes. Watching TP shows that the turbo did move some, but only between 85 and 71.6. After about 7 minutes of idling I took the truck for a drive and simulated town, highway and interstate driving. The turbo moves around just fine, but still very laggy. I was getting a ton of black smoke when taking off from a stop. It took about 1750 rpm before the turbo seemed to come to life and make boost. So all in all, no improvement, possible decline in function.
Before I did the VGT relearn I pulled the EGR valve to check it. Both it and the cooler were dry, no indications of a coolant leak. The valve was dirty but not bad, definitely way better than the first time I pulled it. One thing I noticed though is the valve does not seem to be closed all the way. Could this be part of my problem? The last code I had was a P0404 code. Also, I found a thread in an ag forum I'm on where a failing EGR valve is described as causing a lope at idle, more noticeable when cold, excessive black smoke and sluggishness that disappears around 2k rpm. This sounds very much like my truck. Is there a good way to test the EGR valve that I would be able to watch it open and close?
Wanted to close this thread out. I bit the bullet and ordered an EGR valve from ficm repair and got it put in this past Saturday. I did the relearn and heard the turbo changing pitch as well as watched it on TP, good news. Test drove the truck a bunch and am happier with it now. The VGT% still goes to 85% after idling a bit. However, now when I get on it, the turbo comes off 85% almost right away. Way less lag than before. Also, no white smoke at startup or black smoke when driving.
