Hi all, may be a lengthy post but I shall try and give as much detail as I can. I have a no boost problem with a 2005 6.0. I haven't had the truck long (since the end of June).I picked up the truck, the previous owner changed oil and filters and I checked, the oil was clean.

The first journey was 150 miles at 56 mph no trailer. Two days later a 320 mile round trip, again at 56 mph, with no trailer.

A day or so later I towed a 15,000 lbs 5th wheel 700 miles at 56 mph, mainly motorway, hills, flat, varied territory. Then a further 750 miles at 56 mph, without the trailer.

Over the next week I pottered around couple of days, 6 mile journeys then made a 340 mile round trip to Valencia, no trailer at 56mph. The truck always had tons of power, even up the hills, with 15,000 lbs.

In those 2,500 ish miles, it used no oil, averaged 19.5 US mpg without the trailer @ 56mph and 11 US mpg towing 15,000lb 5th wheel.

Couple of days later after a bit of local driving, no boost! It wont rev over 3000rpm, around 2 psi of boost (on the dash gauge) and wouldn't pull the skin off a rice pudding. It starts perfectly and apart from the power issue, you wouldn't know there is anything wrong. No smoke, sounds normal etc

I appreciate I could do with a Scangauge and have one on order (not easy to get in Spain but should be here next week). In the meantime, this is what I have done / checked.

It gave a trouble code p2262 on a garage code reader.

Checked Map sensor and pipe, which was also clear. Apply regulated compressed air to the sensor, via the pipe and the boost gauge on the dash responded.

Unplugged vgt solenoid and observed exhaust and intake sounds changed and when unplugged there was zero boost.

Icp sensor wire is clean, no oil. I pulled the sensor too and it looks ok

Checked fuel filters (my first thought was fuel starvation)

Removed intercooler pipes, checked and no leaks.

Pulled egr valve, which was dry, with a bit of soot but no bad. I cleaned it, it was closed properly.

Road tested without icp connected, no difference.

Today, I road tested with the ebp unplugged and at first it made 8psi and went a bit quicker but still wouldn’t rev over 3000rpm. Then it went back to 2psi (on the dash boost gauge. I checked ebp sensor and pipe. All was clean and clear.

Do I (could I) need a new ebp sensor? Any guidance is very much appreciated. Is there anything obvious I have overlooked or anything else I can check before the Scangauge arrives, or do I just need to wait and then check the readings? I have spoken with a few 'techs' here but none have any idea. I really don't want to and can't afford to simply start throwing money at it. The best I got was squirt oven cleaner up the turbo from the exhaust side....

It's driving me crazy, especially as it is my daily driver and I need it for work, at lot of which involves towing 5th wheels and travel trailers. Thanks in advance.

Andy

 

HI!
Maybe your catalyst is broken and is pluggning up. My did that.

If you disconnect the dp before The catalyst you can pullit to the side and testdrive it.

 

Andy, welcome to the 6.0 forum. Sounds like you have a good understanding of how this truck works as you are all over the pertinent sensors. As you said, sensor readings will get you on the right path, does the device you used to pull the trouble code have the ability to display sensor values? The ScanGaugeII is handy but not the only way to to get the info you need. MAP, Baro, and EBP values at Key On Engine Off, idle, and 2,500rpm would be great to know.
There is a definite possibility the turbo is sticking and limiting boost but I would not spray oven cleaner in it. There is a good write-up in the Tech folder (at the top of the 6.0 forum page) on the details of turbo clean up. As you may know, it's a variable vane design with no wastegate and it can stick in one position causing the issues you describe. It's fairly easy to pull the turbo off, crack it open, and clean the hot (exhaust) side and maybe the VGT solenoid and linkage. Minimal parts will be required unless you find something broken. If you plan on driving the truck easy and steady as you describe you will want to get familiar with this job anyway as you may be doing it again in the future.

 

Thanks for the prompt responses, guys,

I thought about the cat and the turbo but rightly or wrongly, I dismissed them for the simple reason that one day the truck was fine, parked overnight and the next morning, it had the problem.

With a cat or a turbo I would have expected a gradual demise in performance, not an instant overnight failure, same applies for other possible causes. I removed the turbo intake and it is spinning freely. The fact that when I initially unplugged the ebp, and got a short term increase in power sort of lead me to believe it's an electrical problem. Hopefully my ScangaugeII will be here monday or tuesday to shed some light. In the meantime, I have tried to work methodically and logically through possible problem areas.

As for the oven cleaner... I thought I would throw that in to amuse you I wouldn't dream of it!

Andy

 

Of course, I am happy to be corrected

 

I am in similar position will b watching this thread as well as my own

 

Spinning the compressor wheel doesn't tell you if the vanes are stuck. Check this video, lots of good info but at the beginning he talks about how to tell if it's sticking by reading the commands to the VGT solenoid and comparing that to the boost reading. At about 4:30 he explains the variable vanes.


I've yet to see or read a definitive diagnosis of a clogged catalytic converter on a 6.0.

 

Check ficm voltage, just use a dvom.
Next loosen the 2 bolts that separate the cat from the down pipe and road test it.
Check ebp map and baro pids koeo.

 

Thanks again. Time difference here it's 1am. Will have a look tomorrow and ScangaugeII should be here Monday or Tuesday so I can get the ebp map and baro pids koeo.

Your help is really appreciated.

Andy

 

How do I check the ficm voltage and apologies but what is dvom? Diagnostic Voltmetre?

Andy

 

Did you look at the MAP hose for splits / cracks tight connection? the EBP and hose you could with engine running tap on the sensor and watch the gauge the values should not jump around also spray the EBP hard line with WD or penetrating oil take the sensor off and run a weed eater line through it make sure its cleared out , same with the MAP nipple to Intake , from the sounds of it you did the Map already. Unless you got a sweet deal Auto Zone has the Scan Gauge on the shelf.

 

Dvom is a volt meter.
Ficm testing is in a sticky with tech tools

 

DTC INFO

P2262

Stuck turbo, MAP sensor, MAP hose plugged up; sensor unplugged, or leaking, CAC leaks, intake leaks, exhaust restriction, EBP sensor or EBP tube plugged. This code is set when MGP does not go above 5 kPa or 0.7 psi when the following conditions are met: rpm must be above 2800; VFDES above 20; and EGRVP is below 0.10. All of these conditions must be met for 5 seconds for the code to be set.

 

Yup a bad ficm can cause all those things to appear to malfunction.

 

Thanks again for your help. I checked the map hose and ran compressed air through it which caused the dash boost gauge to move. I have cleaned the ebp and pipe. I shall try giving it a tap today and see if I can test the FICM and shall report back.

I live in Spain and these trucks are rare here. I can't get a ScangaugeII anywhere, so had to order one on the internet.

Andy