I just got some bads news about the 1999 turbo - PeachParts Mercedes-Benz Forum

dtf · #1 02-28-2014, 02:14 PM

My dealer just called and said the reason the check engine light is on is that the boost from the turbo is weak and not what the engine is expecting triggering the light to come on. He quoted a $1900 price tag to replace the turbo.

I have officially crossed into the dreaded - "is it worth it" world with this car now. It always has been problematic and now has 220,000 miles on it. It shifts a little funny sometimes and like a classic '99 W210 has about 4 lights that never work, including the dashboard.

I told him to do the other work like sepentine belt, belt tensioner and front flex disc but my question is can I drive it with a substandard turbo for a while without causing more damage?

Phillytwotank · #2 02-28-2014, 02:16 PM

What is the code for the Light?

Mxfrank · #3 02-28-2014, 02:17 PM

Weak boost is an odd diagnosis. It sounds like the wastegate isn't sealing, or maybe there's a leak in a pressure connection. It shouldn't be a fatal condition.

benhogan · #4 02-28-2014, 02:23 PM

Quote:

Originally Posted by dtf

My dealer just called and said the reason the check engine light is on is that the boost from the turbo is weak and not what the engine is expecting triggering the light to come on. He quoted a $1900 price tag to replace the turbo.

I have officially crossed into the dreaded - "is it worth it" world with this car now. It always has been problematic and now has 220,000 miles on it. It shifts a little funny sometimes and like a classic '99 W210 has about 4 lights that never work, including the dashboard.

I told him to do the other work like sepentine belt, belt tensioner and front flex disc but my question is can I drive it with a substandard turbo for a while without causing more damage?

you don't say where you are but I know a guy in NC who wants to sell his '99. I think he attempted to replace the glow plugs but somehow cross threaded it. so now compression is lousy due to the leak. so now the repair costs more than the car. let me know if you want his info. pm me.

Skippy · #5 02-28-2014, 02:29 PM

Quote:

Originally Posted by Mxfrank

Weak boost is an odd diagnosis. It sounds like the wastegate isn't sealing, or maybe there's a leak in a pressure connection. It shouldn't be a fatal condition.

Exactly. Low boost is rarely from the turbo itself being bad. I'm not sure how the wastegate controls are set up on a 210, but I'm sure someone here does.

Mxfrank · #6 02-28-2014, 02:40 PM

Quote:

Originally Posted by Skippy

Exactly. Low boost is rarely from the turbo itself being bad. I'm not sure how the wastegate controls are set up on a 210, but I'm sure someone here does.

I'm pretty sure the 210 has an electronic wastegate control, so it could be a bad solenoid. But the problem could also be mechanical...on my 201, which admittedly is a different kettle of fish, the wastegate was frozen in place by rust and soot.

dtf · #7 02-28-2014, 02:53 PM

I'm in South East CT. These are good ideas - I 'll take it home after the A service and Felx disc job and look up somebody with more experinece with turbos.

Dealers sort of give up on older cars after a while I've noticed. When I brought my '95 Diesel in to have some codes read they had to 'find' the code reader and then buy a fuse that was blown to get the thing to work.

TMAllison · #8 02-28-2014, 05:40 PM

Is it PO243?

tjts1 · #9 02-28-2014, 05:43 PM

Don't take it into a dealer.

KarTek · #10 02-28-2014, 05:54 PM

Before writing off the turbo, I would hook the vacuum line that's currently going to the transducer and hook it directly to the turbo and see if boost returns. I would be willing to bet there's a crack/leak in the vacuum lines supplying the transducer and turbo and that's causing the weak boost because the wastegate depends on the vacuum to maintain a tight seal and boost pressure.

Phillytwotank · #11 02-28-2014, 06:31 PM

Very likely could be as simple as a vac leak at the waste gate transducer

tjts1 · #12 02-28-2014, 07:07 PM

Check the small vacuum hose going from the intake manifold to the MAP sensor. The MAP sensor is a small gray or black cube attached to the firewall near the intake manifold with a hose coming out of it that attaches to the intake manifold. If that hose has any cracks or leaks or is loose the computer will read low boost pressure and trigger a trouble code. I doubt the dealer even bothered to rule out this hose before telling you that you need a new turbo.

EDIT:

Similar problem.
http://www.peachparts.com/shopforum/3293046-post11.html

KarTek · #13 03-01-2014, 01:51 AM

I was thinking more about this and I don't buy the dealer's diagnosis of "weak boost" setting a code.

I've driven my car in various conditions for test purposes including running the vacuum line directly to the wastegate (full boost all the time) and with the line disconnected (no boost). The only boost related code I have gotten is from running full boost all the time and that code is related to the boost not dropping when the vehicle speed levels off such as after acceleration onto the intestate.

Typically, the ECU will seek to open the wastegate once the vehicle speed has leveled off (cruise) and it looks for a corresponding drop in boost when that happens. If it stays constant, a code will be set (can't remember the number, sorry).

What were the original symptoms? Did the car have plenty of power until the code was set?

KarTek · #14 03-01-2014, 01:53 AM

Quote:

Originally Posted by benhogan

you don't say where you are but I know a guy in NC who wants to sell his '99. I think he attempted to replace the glow plugs but somehow cross threaded it. so now compression is lousy due to the leak. so now the repair costs more than the car. let me know if you want his info. pm me.

I actually might be interested in this car...

dtf · #15 03-03-2014, 11:13 AM

The car had normal power until the CE light came on then no zip but no sputtering or choking. I will check that vacuum line at the fire wall - thanks for the tip!