E320CDI Engine "Pinging" - PeachParts Mercedes-Benz Forum

DUTCH · #1 12-09-2008, 08:38 AM

I just got a call from a friend who has the straight six cylinder E320CDI; and he's getting a pinging in the engine almost like a spark knock in a gasoline engine.

The engine performance is A-OK, but the pinging has him worried. Dealer service can't fix it; and their only recommendation is to try another brand of diesel fuel and put in an additive, although they didn't say what additive to try.

Any thoughts on how to fix this?

aklim · #2 12-09-2008, 09:35 AM

I'd get a 2nd opinion from another dealership.

KarTek · #3 12-09-2008, 09:50 AM

Sometimes my truck runs crappy when I buy diesel from a station that doesn't move too much product. Did he notice the problem immediately after filling up?

aklim · #4 12-09-2008, 09:54 AM

Quote:

Originally Posted by KarTek

Sometimes my truck runs crappy when I buy diesel from a station that doesn't move too much product. Did he notice the problem immediately after filling up?

Had that happen before but not pinging which is why I think a 2nd opinion is in order.

oldsinner111 · #5 12-09-2008, 10:25 AM

I think thoose engines to have trouble with crankshaft sensors.So it could be a issuse with timing of fuel.I'd keep a spare if I owned one.

KarTek · #6 12-09-2008, 12:23 PM

Quote:

Originally Posted by aklim

Had that happen before but not pinging which is why I think a 2nd opinion is in order.

I'm talking about the usual clack, clack, clack at idle turning into a loud, pronounced CLACK, CLACK, CLACK...

Could be fuel of inadequate cetane rating.

Oldsinner111, if you're talking about the trucks, yes they have CPS problems. I shelled out $100 for my spare and then Ford goes and issues a recall... Go figure...

And of course I don't have my receipt any more.

Back to our regularly scheduled programming.

oldsinner111 · #7 12-09-2008, 01:39 PM

No the new Benz diesels.Some are a recall so check it out.

matthias08 · #8 12-09-2008, 05:01 PM

Try a new dealership buddy. I just drove 60 miles each way today only because my local (4 miles) is total crap. kthx

DieselAddict · #9 12-09-2008, 05:42 PM

Quote:

Originally Posted by KarTek

Could be fuel of inadequate cetane rating.

That's what I'm thinking, though directly-injected diesels are much less prone to pinging/knocking than the older indirect ones. I filled up my E300 last week at one of the usual places and immediately noticed pinging & knocking, especially with the engine cold. I suspect it has to do with winter diesel fuel which is diluted with kerosene for better flow which also lowers the cetane index. Prior to this I had California diesel in the tank and the car ran super-smooth on it so it must have been much higher in cetane. I'm gonna add an extra dosage of my cetane booster and top off the tank again. I'd recommend the same to the OP's friend. There are several cetane boosters on the market. My favorite one is DieselPower.

aklim · #10 12-09-2008, 06:06 PM

Quote:

Originally Posted by KarTek

I shelled out $100 for my spare and then Ford goes and issues a recall... Go figure...

And of course I don't have my receipt any more.

http://www.ford-trucks.com/forums/787194-gray-vs-black-cps-test.html

JimSmith · #11 12-09-2008, 06:08 PM

I occasionally get a pinging at light throttle positions. Some cars are worse than others. I have found that RedLine Diesel Fuel Catalyst clears this up, even in very low concentrations. Which leads me to believe the problem is poor fuel, not a real issue with the car. Good luck, Jim

DUTCH · #12 12-10-2008, 02:24 PM

Quote:

Originally Posted by JimSmith

I occasionally get a pinging at light throttle positions. Some cars are worse than others. I have found that RedLine Diesel Fuel Catalyst clears this up, even in very low concentrations. Which leads me to believe the problem is poor fuel, not a real issue with the car. Good luck, Jim

We're talking a CDI engine. Would the catalyst be OK in that engine?

TMAllison · #13 12-10-2008, 02:44 PM

Might change the main fuel filter. It could have collected a bit of water.

DieselAddict · #14 12-10-2008, 03:02 PM

Quote:

Originally Posted by DUTCH

We're talking a CDI engine. Would the catalyst be OK in that engine?

Yes, the I6 CDI's don't even require ULSD.

JimSmith · #15 12-10-2008, 04:44 PM

Quote:

Originally Posted by DUTCH

We're talking a CDI engine. Would the catalyst be OK in that engine?

I asked RedLine when I got the 1998 E300 TurboDiesel, and they said the stuff would cause no damage to my exhaust treatment device (large can in the exhaust). Yours may be different, so give them a call or email them. I know MB suggests you don't need anything, but MB also is quick to point a finger at the US Diesel fuel (my first experience with this phenomena was actually in Germany a few days after I picked up my 1975 from the factory, so I don't really buy the deficient US Diesel fuel story). Jim