Hi again all,

I have done a fairly thorough search, but haven't found a clear answer to this problem. I've seen posts talking about bad injectors and the need to rebuild them, but I don't think this is my problem.

I've had my 300D Turbo for only about 2 months. It had a full tank, to which I added diesel conditioner with cleaner, lubricant, and anti-gelling. I've done a diesel purge with Lubro-Moly and changed both fuel filters.

Last week, I filled her up after a 180-mile trip for the holidays. Now I'm getting a pinging noise when I accelerate, like a gasser would get on low octane gas. The noise is not there at idle or cruise speeds, only acceleration. It's not the normal knocking of a diesel engine. Could I have gotten low-grade diesel? Is cetane boost the fix?

'85 MB 300D Turbo, 254K miles

Hunter did an announcement warning about bad diesel out there. Cetene booster is the answer. You can also add 2-stroke ouboard motor oil to your fuel which will act as an upper cylinder lubricant, also boosting the mileage by approximately 10%. You might wanna add some injector cleaner to that tankful while you're at it, even though you did it on the last tankful . . . til you burn up the bad crap you got stuck with!!!! BTW, the cetene booster is in the "gray" bottle at the auto parts stores.

__________________
1983 300D, the "Avocado"
1976 240D, 4-spd the "Pumpkin", SOLD to Pierre
1984 190D, 2.2L, 5-spd, my intro to MBZ diesels, crashed into in 2002

Are you positive they filled the tank with diesel and not gas. Take the fuel cap off and take a whiff. If it smells at all gassy I'd think about draining the tank down. You could also try a fresh can if diesel in the engine bay with the supply and return lines stuck into it, to eliminate questionable fuel.

__________________

I read Hunter's post about bad diesel but I wasn't sure if adding cetane booster would fix it. I'm going to get an additive with booster and add it to the tank. Not sure about the outboard motor oil though- has anyone else done that? Thanks for the advice.

I've read on here that optimal cetane level is 45-50... does this sound correct?

Since I filled the tank myself, I'm sure it was diesel. I think the car would have reacted more harshly if it were gas. It wouldn't be the first time someone made that awful mistake! (hope it's never me)

is generally in the 38-40 range.

European Diesel (Lots of Which is refined in the U.S.) is Cetane levels of 48-55.

40% of the Diesel Refined in the U.S. is shipped Abroad (More Profit)
[The Excrement they dare not try and sell overseas is offered to you @ your local Pump as "Diesel"]

Injectors,Injection Pumps and your Engine's Health DEPEND on the Quality of
Diesel that's put in your tank.

If I had any question about a Tank of Fuel...
(Especially since U.S. Diesel is CRAP to begin with)
I'd pump it OUT in a Second!!!

Synthetic Two Cycle Outboard Oil is a Viable "Fix" for the Deplorable lack of
Lubricity the Refiners get away with selling in the U.S.

Redline 85 Plus will help with the Cetane levels,BUT you Ain't NEVER enjoy
50 Cetane no matter how much you add to a Tank!

__________________
'84 300SD sold
124.128

Why only synthetic outboard oil in particular?

I have variously read that regular motor oil, any two-stroke oil, etc. will also work.

Not arguing, just asking

__________________


Mac
2002 e320 4matic estate│1985 300d│1980 300td
Previous: 1979 & 1982 & 1983 300sd │ 1982 240d

“Let's take a drive into the middle of nowhere with a packet of Marlboro lights and talk about our lives.” ― Joseph Heller, Catch-22

These problems with poor diesel quality is yet another reason to start running biodiesel. I wish it were more widely available for all people and not only in little hot spots here and there.
Biodiesel is also a great thing to add for lubricity. You only need a 10% biodiesel blend to significantly increase the fuel lubricity.


I forget that most everyone in the US pumps their own fuel. Us here in Oregon get to have someone else do it for us. I always watch the attendants like a hawk to make sure they don't grab the gas nozzle. Only once since 2005 have I had the attendant grab the gas nozzle. But I reminded them before they stuffed in the nozzle.

__________________

Apparently people in New Jersey are also too challenged to pump their own fuel. Been shouted at in both NJ and OR for pumping my own, what can I say but I didn't take the course???

__________________
1999 Mercedes E300TD daily driver sold at 238K miles 106K miles were mine, rust worm got it :-(
2006 Mercedes CDI new daily driver! 56,000 miles May 2016 now 85,625 Apr 2018 and Apr 2019 101,000 miles Apr 2020 109,875. March 2024 135,250

Supposedly the station can get a big fine if you pump you our own at least in Oregon, but I've never actually heard of anyone getting fined. Though, it's legal to pump your own diesel, and you can fill your own motor cycle (since the fuel cap is right in front of your junk). Sometimes it's nice when it's wet and cold and you don't want to get out of the car, but other times you have to wait for someone, and it can be frustrating. Oh well. Creates jobs right.

__________________

Two Stroke Oil is DESIGNED to be Immolated.(Synthetic is ALWAYS Nicer)

"Regular" oils have ALL SORTS of additives to PREVENT Burning.

__________________
'84 300SD sold
124.128

Seems like the synthetics would have additives to prevent burning as well. Do they not?

__________________

Well, I added Power Source's Diesel Kleen + cetane booster on Friday. After letting her idle for a while and driving around a few miles, the pinging seems to have gone away. Of course, all this was after I had to get a jump-start for a dead battery, and then replace the battery ($130!).

Thanks for everyone's help.