Dodging a replacement turbo... p0299 (after reading many posts)

[H0SPlTAL]

I was curbstoned a 2008 GTI FSI, 99000 mi, looks to be in great shape and have excellent service records. an hour after I grabbed it, CEL came on while getting on the highway. p0299 under boost. No whooshing, wining, or hissing noises, no rough idle, no other codes, mpg seems up to spec. It actually runs smooth, but it does seem a little weak on acceleration (what do I know, I've never had one of these cars. but it doesn't feel like 200 hp). OBDLink, a consumer diagnostic platform for smartphones, can put out a graph showing real-time "calculated" PIDs, including boost. I don't know how accurate this is, but it shows boost slowly creeping up from 6 up to ~9-10 psi at about 6500 rpm at WOT. I can't show the graph, because it doesn't give the option to log anything but the mph for some reason. I don't have the freeze frame at this very moment, but I will if it's necessary.

The three shops I asked had almost immediately jumped to replacement turbo. The one I actually took it into, a gas station service garage near my house, quoted me $2400 for a non-oem kit. I came THIS close | | to having him install a used one from a salvage yard for $1100, but decided against it. Another shop, import garage, quoted for $3200. 4-6 hour job, I'm sure I could get a nice big turbo for $3200, but he's talking about a non-oem -replacement-. This car was exclusively serviced at the dealership during its past life, and in one of the most recent records, the "Turbocharger Bypass Valve" was replaced. I thought they didn't have those, but maybe they're talking about the diverter valve. Anyway, that was 13k mi ago. Wouldn't they have put a better version in? Maybe they botched it?

This is literally my first car. I took a loan out to purchase it. I have no other vehicles to drive for commute. My budget doesn't exactly allow for running about town racking up billable hours and diagnostic fees. I have no tools to work on it. My sought advice would be, what is the most economical way of addressing this issue? Can I run the car for an extended period of time in this state until I can save up for a new turbo? How do I find a mechanic that will actually check for easier fixes thoughtfully before deciding on replacing the turbo? How much should I really be paying to replace a turbo parts and labor? Given the symptoms, is it more likely that it's a wastegate issue? I'm in the greater chicagoland area.

 

[ROH ECHT]

You can run it as long as you like with it making low boost.
It is more likely a failed diverter valve(DV)-N249.
It may also be a failing pressure control valve-N75.

Remove and inspect the DV's diaphragm or piston(there are two types/designs)...or just replace it.
The N75 can be tested; its resistance should be 25 ohm. If off 2 or more ohm, replace it. It is not easy to replace due to the three small hoses attached to it.

Don't buy in to replacing a turbo as there are other reasons the turbo will not make the boost it asks to be made. It may even be a small leak along the air inlet between the turbo and intake manifold...and can even be the PCV. One valve in the PCV is meant to shut when boost is present and if it is failing to do so, then it looses boost into the PCV and out into the turbo inlet.

 

[H0SPlTAL]

You can run it as long as you like with it making low boost.
It is more likely a failed diverter valve(DV)-N249.
It may also be a failing pressure control valve-N75.

Remove and inspect the DV's diaphragm or piston(there are two types/designs)...or just replace it.
The N75 can be tested; its resistance should be 25 ohm. If off 2 or more ohm, replace it. It is not easy to replace due to the three small hoses attached to it.

Don't buy in to replacing a turbo as there are other reasons the turbo will not make the boost it asks to be made. It may even be a small leak along the air inlet between the turbo and intake manifold...and can even be the PCV. One valve in the PCV is meant to shut when boost is present and if it is failing to do so, then it looses boost into the PCV and out into the turbo inlet.

Thank you for your response. I’m going to make sure that these are checked at the next place I go to.

I totally get that there are a whole bunch of minor structural issues that can arise after 100,000 mi. I just don’t have the tools or experience to work on it myself. I’m resolved to change that with time.

Meanwhile, every mechanic and their cousin wants to replace my turbo, and I’m fairly certain they do not plan to perform the necessary tests or experiments to truly conclude the need for a turbo if only by process of elimination.

I have found an import shop that exclusively works on VW and Audi, recommended to me by a friend and coincidentally a whole bunch of tuner lads on Facebook. They’re also booked for 2 weeks - a good sign. I’m going to take it there and see what they say.

 

[ROH ECHT]

I’m going to take it there and see what they say.

Probably a good thing to do.
They probably all say turbo because for them it is more money...and the N75 and DV come with and mounted to the new turbo.
It still could be a worn wastegate, but that too can be checked.

 

[H0SPlTAL]

Probably a good thing to do.
They probably all say turbo because for them it is more money...and the N75 and DV come with and mounted to the new turbo.
It still could be a worn wastegate, but that too can be checked.

Double thanks, bud. I appreciate the assurance.

 

[H0SPlTAL]

Update: I found a guy who has been doing turbo repairs for the wastegate, if it is the issue. I’m not jumping to any conclusions, because like you said, it could be any number of issues. But he quoted a repair of $350.

Again though, what do y’all think of those replacement quotes? 2400 for aftermarket, 3200 for OEM? If the car takes 6 hours on the high side, and the Borg Warner turbo costs 1150, and you got bits and bobs cost at $50, shipping at 100, then it seems to me that this shop is charging over $300 an hour! $100 per hour seems more reasonable to me... a shop that I use in the city has their hourly posted on the wall in their office at $89. Even $150 would only cost 2200. Am I missing something?

 

[ROH ECHT]

What it takes to do a repair isn't what they charge. They charge by the allowable time rather than the real time it takes. I've been in for one repair and it took less than one hour while I waited, and was charged for six hours because again, they bill for the time they are allowed. Makes you wonder how a shop of three techs working one day for a total of 24 hours gets away with billing for so much additional labor each day. So rather than receiving (at a $100/hr rate) $2400/day they bill for $2400(x)/day.

 

[H0SPlTAL]

Ok gotcha

 

[H0SPlTAL]

It still could be a worn wastegate, but that too can be checked.

Is there a way to definitely check this without tearing down the car?

 

[ROH ECHT]

You can try finding movement in the WG linkage going into the casting of the turbo, or...you would need to have access to the gate to see if it is tight when closed.
Humble Mechanic talks about this and how to do an inspection through the hole for the B1S1 O2 sensor:

 

[H0SPlTAL]

You can try finding movement in the WG linkage going into the casting of the turbo, or...you would need to have access to the gate to see if it is tight when closed.
Humble Mechanic talks about this and how to do an inspection through the hole for the B1S1 O2 sensor:

 

[H0SPlTAL]

Update: I went to a shop that took down and cleaned the turbo, inspected it, found nothing wrong with the wastegate. More specifically, I asked the shop owner specifically, "was there any play in the wastegate?" "no, it was not that." Not exactly all that helpful, because he said that he and a VW mechanic examined it and could not find a solution for certain. It cost me approximately 300 for the inspection, cleaning, and a replacement diverter valve as a matter of precaution. After picking up the car, cleared of any codes, the p0299 code popped back up after roughly 10 minutes of continuous driving. This mechanic quoted me the lowest price so far for the replacement, at $2200 for OEM. That's actually pretty awesome news, come the need for the replacement.

I set an another appointment with a VW tuning shop that comes highly recommended in the area. For the sake of ensuring that I have accurate info, I think they'll give me my best and last point of reference for what is actually wrong with the car. I don't like to tell mechanics what to do, but I think that mentioning the other inspections it has gone through will help a lot. I will ask them to check the n75 as you mentioned

 

[ROH ECHT]

Yes, do have them check the N75. If they see nothing wrong with the turbo, the N75 resistance should be 25 ohm even though VW has it shown to be OK between 20 and 30 ohm. A tech told me it is actually good at 25 ohm and if it is off 2 or 3 to replace the N75. Mine had a 22 ohm when I checked it and replaced it. Then it boosted like new again. The other failure of the N75 its plastic housing can crack and allow pressure to escape which leads to the WG not functioning properly. This is why you would pressure test the WGA hose from the N75 to see if the WG opens under pressure. Or, just simply replace the N75 if you find it may be less expensive in doing so.

 

[H0SPlTAL]

Update, I've had 5 places inspect the car so far. At least 2 of them are very reputable and deal with these cars. They all say the same thing: turbo must be replaced. I can't get a technical explanation of what exactly is wrong on the part, only that it's "gone bad". Fair enough, I guess you can't always tell exactly what's going on with it but you know what part needs to be replaced.

My quotes so far indicate 2100-3200 all in to replace it. I guess I might as well have them put in a new downpipe while they're in there... again, I can find new OEM turbos for 1250 including shipping. But I saw an itemization on one of the job quotes at 1800 for the turbo... how the fuck are you a mechanic and spending 1800 on a kit I can find on the internet for 1300? IDK man