Losing Power in Higher Gears

[Free Pony]

Hello Friends!
If anyone has advice about repairing my 2004 AI issue I would welcome your thoughts. When I accelerate, my van suddenly loses power and it seems like the turbo stops working. I’m going 40 mph on the freeway. I sometimes gradually can work my way up to 60mph, but it never feels like the turbo kicks in to boost. If I pull over and turn the engine off and restart, it’s like the system is reset and I can accelerate with umph again until a certain point and then the umph just goes away again. I can plug in a code reader while I’m driving and it drives fine until it throws a code. But if I clear the code while I’m driving, it will reset and I have my power back! I don’t remember the code right now but I will pay attention and come back and add it to the post after my errands today. Has anyone else experienced this? Hugs to everyone!

[SunchaserV]

FP
I assume this is a MB diesel. Have you recently had it in the shop or done some DIY activities? Your fuel filters are clean and other PMs up to date by the book I trust? There are both time and mileage requirements noted in the MB multi page PM book. With a 21-year-old diesel significant and ongoing TLC is needed to keep it in good running order.

In any event, I suggest you take it to a capable MB shop. There are several possibilities as to what is going on with some simple and others involving a safety feature which reduces power to prevent a problem.

[Free Pony]

@SunchaserV Thank you, from the P0299 code it looks like the boost pressure sensor. I’m looking around for one now. I like to do my own work��

[SunchaserV]

FP
The P2099 code can be caused by several things in addition to the sensor:
-- Bad Turbo,
-- Leaky EGR pipe
-- Dpf filters
-- Manifold gaskets

Look for soot in the turbo area when working in that area.

[Free Pony]

@SunchaserV I will look for soot! Thank you! Since it isn’t throwing any additional codes, and it regains power as soon as the P0299 code is erased, my hopes are high that It is a simple $89 sensor.

[InterBlog]

OP, my money is on your EGR valve needing to be cleaned or possibly replaced. Try cleaning it first.

There’s a rumor going around that T1N Sprinter EGR valves fail in an all-or-nothing dramatic fashion but no, they can instead act like a ghost in your turbo machine. Ask me how I know this.

[Free Pony]

Wouldn't the EGR throw its own code though?

[InterBlog]

Originally Posted by Free Pony

Wouldn't the EGR throw its own code though?

Ours did not. We struggled with it for several years before finally figuring it out on the basis of symptoms rather than codes. We have a 2006 Sprinter.

[Free Pony]

Originally Posted by InterBlog

Ours did not. We struggled with it for several years before finally figuring it out on the basis of symptoms rather than codes. We have a 2006 Sprinter.

Oh man! I’m sorry to hear that! Without a code is there any way to test the EGR? Or do you think I should just replace it?

[SunchaserV]

Originally Posted by Free Pony

Oh man! I’m sorry to hear that! Without a code is there any way to test the EGR? Or do you think I should just replace it?

Careful here, at $500+ for valve alone take a minute or two. Sure remove it but insure the fault is not with associated EGR connections. At 22 years old it could be several things as mentioned earlier.

Diagnostic tools include a multi meter and vacuum device. If electric is the problem a code may have been shown, but if vacuum related a code may not appear and the valve be OK.

[InterBlog]

Originally Posted by Free Pony

Oh man! I’m sorry to hear that! Without a code is there any way to test the EGR? Or do you think I should just replace it?

Speaking solely about myself here, in my opinion if I am *dumb* enough to continue to operate an 18 year old T1N Sprinter with a failure point as severe as the EGR valve is known to be, then I better be *smart* enough to carry a spare EGR valve with me at all times because guess what?? There are maybe 2 whole places left in America where they can be obtained off the shelf in real time, and if my turbo is on-again-off-again, then I have a snowball’s chance in hell of making it to either one of those places. (One of them is Million Mile Sprinter in Philly and the other might be that guy in Kansas.)

I suggest digging out some YouTubes and seeing if you can DIY an investigative approach before buying one, however, because you need to ascertain the facts of your situation. You will know if the EGR valve is potential culprit because it will be caked with soot and the little slide-y part will not be sliding very well.

You might suspect from my current tone that said T1N Sprinter has been giving me problems today. You would be correct about that. Not with its EGR valve but with other operations.

[Free Pony]

Thanks everyone! My big turbo hose has a tear in it - should be coming in today. After I taped it up, my boost came back online! The van was never in “limp mode” - just wouldn’t kick on the turbo after the P0299 code came up. I hope replacing the hose and cleaning the intercooler and EGR valve will fix the black smoke issue. I’ll save up money and have an EGR valve as a back up cuz I’m not rich but a word to the wise is enough!

[mythbuster88]

Originally Posted by Free Pony

Thanks everyone! My big turbo hose has a tear in it - should be coming in today. After I taped it up, my boost came back online! The van was never in “limp mode” - just wouldn’t kick on the turbo after the P0299 code came up. I hope replacing the hose and cleaning the intercooler and EGR valve will fix the black smoke issue. I’ll save up money and have an EGR valve as a back up cuz I’m not rich but a word to the wise is enough!

What black smoke issue?

[dsc789]

Originally Posted by Free Pony

Hello Friends!
If anyone has advice about repairing my 2004 AI issue I would welcome your thoughts. When I accelerate, my van suddenly loses power and it seems like the turbo stops working. I’m going 40 mph on the freeway. I sometimes gradually can work my way up to 60mph, but it never feels like the turbo kicks in to boost. If I pull over and turn the engine off and restart, it’s like the system is reset and I can accelerate with umph again until a certain point and then the umph just goes away again. I can plug in a code reader while I’m driving and it drives fine until it throws a code. But if I clear the code while I’m driving, it will reset and I have my power back! I don’t remember the code right now but I will pay attention and come back and add it to the post after my errands today. Has anyone else experienced this? Hugs to everyone!

The van is going into limp mode. Could be any number of sensors. You don't have to use DEF in yours so that simplifies it some. You may or may not have an EGR valve, but that would be the first thing to check. Rislone makes some diesel additive that works for some to clean the EGR. Have you checked/changed your air filter lately? That can cause issues as well. I know it can be expensive, but it might need a dealer technician to diagnose beyond the codes...

[kingcharles]

Replacing the turbo air hose should fix the loss of power issue. If you look at hose while someone else races the engine you will probably see the tear in the hose open up which kills the turbo.

[ITSNO60]

Originally Posted by mythbuster88

What black smoke issue?

It's in his other thread https://www.airforums.com/forums/f24...ml#post2780065