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- - W124 E420 Bogging (http://www.peachparts.com/shopforum/showthread.php?t=267421)

It' not that. I can get to a high rpm and there is no missing. When I drove it this weekend I was able to put in in 1st and 'cruise' around the neighborhood just fine at 4k-5k RPMs.

As long as I don't 'step' on it and build speed slowly, there is not an issue. It's also easy to get to those high revs in 1st because it requires less throttle than doing it in a higher gear.

Thanks for the lengthy reply, though. May help someone in the future.

Quote:

Originally Posted by emerydc8 (Post 2482533)

Do you hear any valve pinging when you initially accelerate?

If there is any pre-ignition or detonation (valve ping), the computer will retard the timing--I think by as much as over 20 degrees--and this could cause a "bog" under load.

The pinging can be caused by carbon deposits in the combustion chamber (piston tops and valves) that pre-ignite. Detonation can be caused by a low fuel octane, clogged injectors, bad EGR (the EGR introduces relatively cool air into the engine), over-advanced ignition timing (not likely in your case), defective knock sensor, wrong or bad spark plugs, or fuel pressure under load is too low (check the fuel pressure regulator). I'm sure I left some out of this list.

I had a problem with my 400E where it would bog under a load, but I could hear the pre-ignition noise and I backed off, so I never really pushed it into the higher RPM range; but I know it would have really bogged down (or blown up).

The solution for me was to run 2 quarts of Chevron Techron with a full tank of gas (twice). I don't know if it was a clogged injector or a carbon deposit somewhere in the combustion system that was causing it to pre-ignite, but the Techron was like magic. I started to see a difference within 100 miles and after the second tank, it never recurred.

Maybe you've already tried this. If so, disregard. If not, it wouldn't hurt to try. I would recommend changing the engine oil after running 4 quarts of Techron through the engine, though.

Quote:

Originally Posted by deanyel (Post 2483126)

And you're working another fine testimonial for non-ASR cars.

Given that it's been a year, I thought I should get after it again. It's still sitting there and I don't know what to do. I hate to trash it or sell it as it's a nice car other than the minor fact that I can't get it to run.

I'm going to give it one more try. Current options:

1. Send ETA to Beckman to diagnose. It's $125 for diagnosis only. I've had 4Mercedes rebuild it and re-test it (sent in twice) and they think it's fine. But, based on my general experience with them, I'm not 100% sure.
2. Take to a local garage that I have not tried.

I'm leaning towards #1, because a)I can rule it out all together if that's not it b)know the issue if it is and c) if I don't do #1 and do #2, I still may not know (or have them spend a couple of hours doing diagnosis that is wasted.

after sitting for 10 days or more I have a similar problem as emorydc8 , but it only starts once the engine goes to closed loop i.e. warmed up. then after driving through this situation for about 10 minites it clears up and the engine is great, until it sits again. I'm pretty sure it is the injectors somehow getting partially plugged, are there any service bullitens covering oem injectors?

These are complex cars, but they're still cars!

I think this car is being overanalyzed (I'm guilty of doing it to mine too, in the past)

My car is having the same issue, but only after sitting for 6 months under some trees. In fact, the 6 times I started it and ran it in park over 6 months, and the first time I drove it a few days ago, no problems - but now the fuel gauge is on the last white line, and it's bogging.

Sitting for 6 months, nothing until the car jostled around.....coils and plugs replaced 20k ago.......

It's almost certainly water in gas/trash/clogged filter or injector.

I'm going to be running a big boy bottle of Techron and a fresh tank of VPower. You guys should do the same (and swap fuel filters while you're at it)

Also, don't panic over codes and idiot lights. There are so many contacts to get dirty, and so many low-voltage situations to cause these lights that I would almost never believe what the scan tool or light says until I'd checked all the most basic components first

The airbag light comes on in my SL when I slow to idle speed and have all the accessories running. It's almost certainly not the airbag, rather the car shutting secondary systems down when the voltage isnt sufficient (battery, alternator) as these cars will do - wiring, grounds, contacts, all these things will set your dash lights ablaze and everyone goes screaming "oh those damned ASR cars!"

I second Will's suggestion.

I just went through "bogging" with my '95 E420. Sporadic bogging - usually after the car running OK for a few minutes, if shut off, upon restart the bogging would appear almost mysteriously.

Suspecting water in the gas or clogged fuel filter (which I had had once about 3 years ago)....I replaced the fuel filter. No improvement.

So, I drained the fuel tank (just aft of the fuel pump), and put in a full tank of fresh, high octane (Sunoco), and threw in a bottle of octane boost for the heck of it.

Voila, problem cured. Remains cured for about 3 full tanks now.

So, while not the solution to all M119 engine problems, definitely a solution one should try as it does not require lots of work or replacement of expensive parts.

The fuel had been suspected so the gas was tested, pressure tested at tank and at engine, gas replaced, etc, etc. No change.

Quote:

Originally Posted by jkazzoun (Post 2735407)

ETA is fine. Beckman checked it and swears it's fine.

Should the MAF glow red (hot) when the key is turned all the way (prior to start)?

@ jkazzoun

I feel you, Im having the same problem. I have a 1995 E420 W/O ASR.

When Cold, It starts perfect, no shaking, its just fine, I take off with the car
and once it starts warming up, it starts to shake a little, but after like 10 mins, it
starts to really stall, till it eventually dies, and then I want to start it again and it chokes and wont start.

I guess I am going to start Chasing Ghost too. Good Luck.

Replace ignition coils. It's just about impossible to bench test them due to replicating the exact driving conditions. If the coils are original, or just old replacements, replace them.
I didn't read all of the replies here, but if the "bogging" occurs after driving for a while, or intense highway speeds, it's the coils...