I have a 2005 Ford F250 6.0 with 102,000 miles. I've had a problem with it for about a year or so now. Sometimes when I'm climbing a hill I'll get a code of low boost PO2299 and then a high boost PO234 as well. I am using an Edge tuner but have only had it on factory mode. I was pulling a small bass boat for about 70 miles yesterday and we got the codes several times again. I would clear the code with the tuner. 90 percent of the time this only happens when we are climbing a hill. Some times when I leave off the accelerator I can hear the tubo "growling" as it spools down. (I hope I said that right.) I also just recently got two new codes PO478 Exhaust pres CTRL Valve Hi Input and a PO677 Glow plug #7 Circ failure.

I've had the EGR delete, new oil pump/cooler, aftermarket exhaust, coolant filter and some other stuff I'm forgetting at the moment. I've taken a Ford mechanic for a ride but the truck didn't mess up of course. Can anyone please help me in finding out what is wrong. I can't take a chance of this truck not even making it around the block anymore. Anyone have any suggestions on fixing my truck? I don't have any eny engine readings at the moment. My friend has a scanner and I'm hoping he can check it out over the weekend.

Many thanks,

Chap

 

My 2005 did the same thing. Every time it was a sluggish turbo. The last time Ford rebuilt it and it still wasn't right. They had to replace it. It's either the turbo or vgt solenoid. My money would be on the turbo. My truck went thru 4 of them and Ford could never determine why so many. My truck was also worked hard at times, 31' fifth wheel. Ford finally did a buy back on it.

 

I guess it would be best if I start with the VGT Solenoid. No worse than the stealership throwing parts on which doesn't fix it. I appreciate the help. Going to wait for additional remarks. I also forgot to mention that going up the hill the engine "bucks" every once in a while. No one can figure this one out either. Any suggestions on this? Thanks again!

 

I would start by checking to see if the exhaust back pressure sensor tube was plugged. The sensor is bolted to the thermostat housing. I know on some 05 or 06 trucks there was a different arrangement on how the EBP sensor was mounted. Regardless, it's an easy check and clean. I'd also check the MAP sensor hose and nipple on the passenger side of the truck to make sure they're clear. The MAP sensor nipple is in the intake manifold. I can't find the P0234 code in the 6.0 bible list, but most of your symptoms point at a faulty EBP sensor reading (probably the tube plugged). If that doesn't cure your problem, I'd clean the turbo. The VGT would be the last thing I'd suspect, but occasionally they do go bad.

 

Tim, P0234 is a signal to the pcm of a dangerous overboost.

 

P0234 - Turbocharger over boost detection code stored and wrench warning lamp illuminated when a turbocharger over boost condition occurs. TSB 09-24-03. The only trucks that will set an overboost code P0234 are the 05-07s with the latest ford calibration. The calibration will set the wrench light and derate after 28 PSI (or 28.6 psig).

Seems like a plugged EBP tube (causing a false low EBP reading) could cause the turbo to over boost, but I don't know if there are "preventions" in the tuning.

Sure would be handy to see MAP, EBP, and VGT % duty cycle data at various conditions.

 

Well everything I would add seems to have already been said.
So I guess I will hang out up here in the peanut gallery and toss shells on the floor.

One thing I would ask is what is your driving habits like and how ofter?

 

That explains it, thanks guys.

 

Hope you aren't getting the crazy flooding Tim. We have relatives who might be getting hit fairly hard in Oklahoma!

 

No, we aren't. Actually, when they opened the gates on the Arkansas River down below it took away almost all our water and the farmers have been able to get in and work their fields, although it's very late in the season for rice to be planted. Where we used to live in Arkoma, Ok. is in the water or, at a minimum, surrounded by water, so I'm very glad we're away from there. To say the least, we've been blessed to miss the catastrophic flooding facing the folks along the Ark. river, but still have the White to contend with later on. It's absolutely incredible to witness what's going on.