Misfire/knocking noise
I have 2013 GL350 with about 95k miles. Yesterday, I drove the car back from a 500 mile trip. Stopped and shut the engine off for about 15 min and started driving again. While climbing a hill, the engine became a little shakey (sort of like a misfire), the transmission downshifted. I immediately took my foot of the gas pedal began braking to pull off to the side of road. As I did this, the engine shut off. When stopped the engine would not turn over. I could hear the starter click, but not turning of the engine. Battery voltage checked at 12.0V, No low battery sign ever popped on the dash. A tow truck gave me a jump start. The engine started but seemed a little shakey at idle. Alternator voltage and current are good varies between 13.5 and 14.2V and shows charging the battery. The engine did, eventually smoothen out at idle, but still misfires under load and also makes a knocking sound while misfire at 1600+ RPM. What could be causing this? Can a battery just completely die suddenly like this? I have no check engine lights either. Could it be a bad fuel injector?
The car had an oil and filter change using approved 229.51 oil (Mobil 1 ESP 5w30) and WIX oil filter at the beginning of the trip. The only thing that I can think of is that I ran 3/4 of a tank of biodiesel blend between 5 and 20% because I was in Illinois and couldn't find straight diesel. I have since filled with straight diesel, but the noise and misfire remain. Do I need a new battery?
Sadly the vehicle is 2 wks outside of MB COPO warranty!
Sorry for the long post, but just wanted to give all relevant history.
Thanks!
The engine actually runs just fine on 5-20 biodiesel, but bio is also a powerful SOLVENT. If you have never run bio, your truck probably has plenty of completely normal diesel deposits in the fuel system.
Run a tank of bio for the first time in 95K and suddenly some of those deposits are set free and can clog filters, or worse, injectors. Meanwhile, and ironically, a driver in IL is doing fine because they've been running bio the entire time.
Last edited by cadetdrivr; Oct 16, 2018 at 11:32 PM.
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Just take it to Indy guy, probably couple of them to make sure if it can be fixed.....If it cant, then sell it of Craigslist...