400e smoke on WOT only - PeachParts Mercedes-Benz Forum

Will_w202 · #1 09-18-2008, 12:14 AM

Recently purchased, has had by-the-book 7500mi oil changes, reg service, dino oil. 161k miles. Any WOT downshift, like 65-85 tonight in 2nd gear, I could see pretty thick smoke in headlights of the car behind me, like my old 123 diesel! Not sure of color because it was dark out. Also, drove the car about 140 miles today, parked it, and cranked it 3 hours later. There was vapor coming from the exhaust, which seemed odd since it was driven so long and so recently - however, it was a very humid day today, 87%. I also ran a 20-gal bottle of techron, the bigger one, to about 10 gallons of V-power, if that means anything.

Car appears to be on original head gasket, valve seals, guides, and timing chain (chain guides replaced). I have had it for a week, and have no fluid leaks visible underneath the car. It's going in Monday for a 30k service at the best indie in town, partly because they go over the whole car as a bonus on that service.

Could it just be blowing crud out, maybe amplified by the techron? Maybe running rich, caused by....?
This is the strongest motor I've ever owned. Pulls like all hell is breaking loose.....makes my C350 (268hp) feel like a 4cyl.

mpolli · #2 09-18-2008, 12:38 AM

So that's a '92? Anyway, all I know is when you WOT the EFI system goes into open loop and dumps extra gas so that could just be SOP. My advice, just don't do that! But someone else MIGHT have a better answer...

Will_w202 · #3 09-18-2008, 10:10 AM

lol....but it's so much FUN!

It's actually a 93. Just went out for a Starbucks run ( I was out of coffee filters, dammit) 9:30am, 71*, low humidity. No smoke/vapor on startup, at all...

jhodg5ck · #4 09-19-2008, 05:15 PM

I'd say you may be in the 'blowing crud out' stage as you mentioned..plus @ night you'll see all Sorts of stuff you wouldn't see otherwise during the day.

WOT on an M119 is a Good time and they'll take it so Have fun

Jonathan

emerydc8 · #5 09-19-2008, 06:02 PM

For what it's worth, mine has done that since I bought it. Once you accept the fact that the car can't get out of its own way, there's not much reason to hot rod it anyway.

jhodg5ck · #6 09-19-2008, 06:08 PM

Quote:

Originally Posted by emerydc8

For what it's worth, mine has done that since I bought it. Once you accept the fact that the car can't get out of its own way, there's not much reason to hot rod it anyway.

I think there is something Seriously wrong w/ your 400E. 270 odd horsepower moves them out quite nicely IME!

Jonathan

emerydc8 · #7 09-19-2008, 06:57 PM

I'll take your Z4 instead.

jhodg5ck · #8 09-19-2008, 08:22 PM

It's fun to beat the S*&t out of, I'll give you that!

Jonathan

Will_w202 · #9 09-19-2008, 10:09 PM

It's definitely more responsive to light throttle inputs than my C350......that car will smoke the 400 from a stop though, but hey, it has 7 gears. Midrange at part-throttle, you can feel the extra 35lb/ft of torque in the 400. Helluva motor. Saw 140 last night, and that's on old plugs/lumpy idle!