My GL350 misfiring Copart saga - PeachParts Mercedes-Benz Forum

popimor · #1 12-28-2019, 01:40 AM

Too long, didn't read (TLDR) version at the bottom!

So, after many years since I sold my 300d, I purchased a 2011 GL350 Bluetec at Copart with 88k miles and a clean title. The listing said it was running, but wouldn't drive. No exterior or interior damage beyond superficial scratches and a small door dent. I am in California visiting my sister for Christmas, and live in Michigan and plan(ed?) on driving the GL back.

So, I figured the GL had a low battery and auxiliary battery that might be causing it not to shift from park based on it being shift by wire. I showed up to grab it from the yard with a couple of Duracells AGMs in tow that I purchased on the way to the yard. After a surprisingly short process, they brought the beast out on a forklift.

I had already called a tow truck that was going to show up in 30 minutes. Either I would get the GL running would feel good enough about its condition with it shifting into gear and just have it towed to my sister's, or to the MB dealer nearby where I already had an appointment.

1. I checked the oil, all good (looked somewhat dirty, but no water and no coolant).

2. I started the Mercedes which cranked very slowly, and ran very rough. It would not shift into drive. The clock spun (sign of low voltage, so I hear). I ran it maybe 2 minutes.

3. I scanned for codes and got.

- 156000 The negative control deviation of exhaust gas recirculation control is
too high.

- 108800 The signal from component B6/1 (Camshaft Hall sensor) is faulty.

- 10E300 The number of combustion misfires at cylinder 4 is too high.

- 10E500 The number of combustion misfires at cylinder 5 is too high.

- 10E700 The number of combustion misfires at cylinder 6 is too high.

- 10E800 The number of combustion misfires is too high at several cylinders.

- 155500 Control module has an internal error.

4. I cleared the codes I could with my cheap scanner.

5. I took the starter battery and auxiliary battery out, and put the new batteries in. -- Who the hell decided to put these under the passenger seat? It's 1.5 hours book time. -- It took me 50 swearing, sweating minutes during which the tow truck driver, Dennis, showed up and put the car on his truck. Dennis the tow truck driver happened to be a Mercedes enthusiast who took a 300d 740k miles (why did I sell my 300d?!).

6. I started it up and it cranked somewhat slowly and the misfiring continued (maybe my new battery didn't come fully charged?). The clock still spun for a while. All of the codes eventually came back. I don’t think I let it run long enough to get up to temperature. It sounded pretty rattle like and like some detonation was happening. Dennis thought maybe the extra rattle that happened sometimes was bad timing chain guides. No smoke out the tailpipe to speak of. But I was able to shift it into drive!

7. I decided to take it to the dealer so I wouldn’t get distracted and not spend time with my sister and family (my wife and kids are in tow). Maybe this was foolish (probably not as foolish as purchasing a vehicle from Copart). I haven’t been to a dealer in a long time, and never for service. But I figured they had the Star scan tools and parts there. I don’t have much in terms of tools here.

8. The dealer texted me today after a long wait and said bad news. The compression in cylinders 2 and 3 are really low. I asked for the psi readings, and then found they had done the Star Compression test based on rpms while cranking the vehicle starter. I got the result from them below. Important note, I am speaking to a concierge at the dealer, not a mechanic.

Results:
Cylinder 1 0 min-1
Cylinder 2 368 min-1
Cylinder 3 496 min-1
Cylinder 4 0 min-1
Cylinder 5 0 min-1
Cylinder 6 0 min-1

Here lie my main questions:
A. Can the Star diagnostic get a good read of rpms when the crank position sensor is bad? And could all of my symptoms actually be related to this?
B. Would a low battery potentially cause the test not to work properly?
c. Is there any chance this is caused by regular gas in my diesel?

From what I am reading here, all cylinders but two would have no compression, and the two that do are low compared to the 730rpm or so I would expect based on another example I saw online. I am surprised it would start in this situation.

I am really tempted to go grab the GL first thing in the morning. Get the crankshaft position sensor and an EGR valve from the parts department, put them in myself and make sure the battery is fully charged and see what happens.

Alternately, if this test is accurate and my engine is toast, I will have it shipped back to Michigan without the interim headache and put in a new engine myself in January (does anybody know a good shipper?).

What do you think, other than I make bad decisions about vehicles sometimes?

9. Tomorrow morning I get to talk to the shop foreman, and will get more detail. What should I ask him beyond did you charge the battery, and could the crankshaft position sensor be causing bad readings? Could it be Dennis' the tow truck driver's theory about the timing chair guides, or maybe worse the timing chain jumped and I have valves all over inside my engine and it still magically starts?

I have attached their test results for reference.

Too long, didn’t read (TLDR).
Does the Star Compression test based on RPMs provide accurate results if your crankshaft position sensor is bad or if you battery is low? I have some strange results from the Star compression test above, that don’t seem correct with 0 on four cylinders and 368 and 498 cylinders 2 and 3 respectively. I get to talk to the Shop foreman at the MB dealer who oversaw the test in the morning. Is there anything I should ask him beyond was the battery charged, and about the crankshaft position sensor? I am tempted put the Crankshaft position sensor in and try it out. The GL would start and create quite a racket when I dropped it off.

nulu · #2 01-05-2020, 12:01 PM

Its possible for chain to have jumped time, these engines are needing chains at your indicated miles, but first make sure it dosent have gasoline in it