Dead E420
 

Good morning! Can anyone offer a suggestion on a current problem? I have a '95 E420 with the M119.975 V8 engine. This ia a relatively low miles car w/ only 135K miles. I went to start it this morning, which it did, and then abruptly died. When I tried to re-start it, it sounded as if it only had compression on a couple of the cylinders. I assumed the timing chain broke, but heard no noise. I pulled it in the shop, pulled the oil filler cap and distributer caps off, and all four cams are definitely rotating. Can the tensioner on this engine allow enough slack for it to jump time so dramatically that it won't have any compression?? Does anyone have any idea what could possibly be wrong??

Thanks, txquigly

The upper timing chain rails are plastic and can easier break by that mileage. When they do the timing chain can jump a tooth or two. I would take off the valve covers and see what you find. You could also take off the oil pan, which is quite easy to remove on your car (easier than the valve covers) and see if you find any plastic parts.

Thanks, I'll drop the pan Monday and let you know what gives!

Before you pull the pan, pull the engine codes. I think the 95's have the LED light - at least see if you can get the base codes (use search function on this site).

Odds are that either your wiring harness is history, or your ignition control module bit the dust, and your engine was running in limp mode (sound like a 4 banger, did it?)

If you're lucky, it's just the harness. Also, check and either clean or replace your rotors and caps (if still so equipped).


Again...before loosening bolts, check the trouble codes! If you get a schload of them, it's probably the harness.

Good Luck!

-Larry

Why would losing the harness or ignition module dump all the compression? It sounds like all but one or two holes have the plugs out of them when you crank it! Thats why I thought the timing chain broke and was so surprised to see the cams still turning when I looked deeper. Also, it never went into limp mode...it started just fine, then promptly died...then re-cranked with no compression or even a slight attempt to fire a hole. By the way, what's this about an LED light? I'll search codes tomorrow and post later.
Thanks again for ANY input!!!

txquigly

Here is where I am hoping you will find it (the button & LED )

The red arrow didn't show up too well, sorry bout that.

Not that it makes any difference, but I believe your engine might be a M119.985 not the 119.975

I think it's a .975, and 1996 is a .985.

I highly doubt its a mechanical problem inside that motor. The 119's proved to be fairly robust.

txquigly,

Any news??

I agree with Larry, scan for codes first. Check out Jim's site:

http://pages.prodigy.net/jforgione/MB_S500.html