240d
Always used Power Service according to directions.
Recently in warmer weather I started using about 1/2 of what it called for and noticed the engine got noisier. Last fill used about 2x normal and it seems to be getting quieter.
Anyone else notice anything like this?

Its 100% psychological.

I disagree...I have had experiences when I have filled my tank and noticed some fuels cause more clatter and nailing, especially at idle. I have more trouble with Mobil than with Sunoco so I usually use Sunoco but when forced to use Mobil I add some power service (white bottle in winter, grey in summer) and it does quiet it down. Both products have additives which raise the cetane of the fuel so I don't think it is psychological.

__________________
Marty D.

2013 C300 4Matic
1984 BMW 733i
2013 Lincoln MKz

There may be a psycological component to it but I agree it has a lot to do with the cetane leval and quality of fuel.

I bought fuel for the truck once at a station that I had never bought from before and it immediately started a noticable idle knock which went away instantly when I refilled again a month later. (I don't drive the truck much).

__________________
-Evan


Benz Fleet:
1968 UNIMOG 404.114
1998 E300
2008 E63


Non-Benz Fleet:
1992 Aerostar
1993 MR2
2000 F250

All in the mind.

__________________
Not MBZ nor A/C trained professional but a die-hard DIY and green engineer. Use the info at your own peril. Picked up 2 Infractions because of disagreements. NOW reversed.

W124 Keyless remote, PM for details. http://www.peachparts.com/shopforum/mercedes-used-parts-sale-wanted/334620-fs-w124-chasis-keyless-remote-%2450-shipped.html

1 X 2006 CDI
1 x 87 300SDL
1 x 87 300D
1 x 87 300TDT wagon
1 x 83 300D
1 x 84 190D ( 5 sp ) - All R134 converted + keyless entry.

People should agree to disagree...if you ever heard one of these motors run on pure diesel purge you would know that what you burn can certainly have an effect on how noisy the motor is. Somewhere on this site is a video which demonstrates it rather dramatically...you hear clatter and nailing one minute and as soon as the DP goes in the engine goes to "sewing machine mode". Some people claim biodiesel also runs that way.

I suspect the cetane of DP is very high too and simulates "super premium" fuel. If Power service is able to increase the cetane then why wouldn't you believe it could quiet the engine?

__________________
Marty D.

2013 C300 4Matic
1984 BMW 733i
2013 Lincoln MKz

It would be very expensive to run on pure Diesel Purge to get from A to B. But I cannot agree with you more that diesel engine runs quieter with biodiesel or WVO/SVO as I run my diesel on WVO.

As for adding additive or diesel from different gas station then it is all subjective. People claims all sort of things with better mileage, quieter engine, more power, cleaner injectors etc etc. Who knows.

If it makes one happy then spend the $$ and just keep doing it.

__________________
Not MBZ nor A/C trained professional but a die-hard DIY and green engineer. Use the info at your own peril. Picked up 2 Infractions because of disagreements. NOW reversed.

W124 Keyless remote, PM for details. http://www.peachparts.com/shopforum/mercedes-used-parts-sale-wanted/334620-fs-w124-chasis-keyless-remote-%2450-shipped.html

1 X 2006 CDI
1 x 87 300SDL
1 x 87 300D
1 x 87 300TDT wagon
1 x 83 300D
1 x 84 190D ( 5 sp ) - All R134 converted + keyless entry.

I guess my point was that if it is possible that fuel quality affects the noise of the engine (which you even affirm) then why would using an additive that claims to increase cetane result in only a placebo effect as you claim it must be? It certainly is possible that, if the product increases the cetane, that the engine could run quieter and therefore the improvement is not in his (or my) head.

__________________
Marty D.

2013 C300 4Matic
1984 BMW 733i
2013 Lincoln MKz

May be you are right but most messages I read here is psychological. for me.

__________________
Not MBZ nor A/C trained professional but a die-hard DIY and green engineer. Use the info at your own peril. Picked up 2 Infractions because of disagreements. NOW reversed.

W124 Keyless remote, PM for details. http://www.peachparts.com/shopforum/mercedes-used-parts-sale-wanted/334620-fs-w124-chasis-keyless-remote-%2450-shipped.html

1 X 2006 CDI
1 x 87 300SDL
1 x 87 300D
1 x 87 300TDT wagon
1 x 83 300D
1 x 84 190D ( 5 sp ) - All R134 converted + keyless entry.

Very true in my expireince. B99, DP or other additives (I like Redline 85) mixed with D2 definately changes the combustion charectoristics which positively effects how the engine sounds, especially at idle.

Whether or not it helps is another question.

__________________
Terry Allison
N. Calif. & Boca Chica, Panama

09' E320 Bluetec 77k (USA)
09' Hyundai Santa Fe Diesel 48k (S.A.)