Hello fellow benz fanatics. I owned a 76 300D in high school, but couldn’t afford to keep it. If this forum was around back then, I sure missed out – What a terrific resource!!

My passion never died, I am now the proud new owner of a 1980 280E. The car was a terrific deal, but on the down side, I purchased it from a dealer, who of course didn’t know, or didn’t disclose the history of the car. I have spent many hours learning more about my car by reading threads on this forum; however, I still have a number of questions. I am certain that at least two of the problems below are interrelated, but I’m not sure which ones they are. I would greatly appreciate help putting this puzzle together:

1) I have a vacuum leak - How does a leak in the vacuum system lead to poor engine performance, and how much performance can be lost? I did a compression test, and found that all 6 cylinders had compression between 95psi and 115psi. I found a thread that referred to normal compression in the M110 engine as 175psi-185psi. I did the teaspoon of oil down there sparkplug well test, and that brought the compression to 125psi. Do I have worn rings, or could the vacuum account for compression as low as 95psi?

2) My car barely runs when I first start it due to a loping idle (when I hold the gas down, it takes about 4 seconds for the engine to respond at all, at then the revs go through the roof) After I let it warm up a little, the idle levels off, but when I push the gas to the floor, the car barely moves, until it has warmed up even more. The dealer did say something about the warm-up regulator being faulty. Could this problem be attributed to the vacuum leak, or a faulty warm-up regulator.

2) I do have a vacuum line leaving the #6 intake manifold, but there is a hole right beside it (closer to the front of the car). I imagine something should go in this hole, such as a vacuum line, or a sensor. Does anybody know what it is, and if it is a vacuum line, where it goes? The vacuum line going to the FD is capped with a screw, so my guess is that this line should go to the hole in the #6 intake manifold.

3) After driving 100 miles at 75mph, I stopped my car at a gas station and found a huge puddle of oil under the car. Upon closer investigation, I found the oil had come from the crankcase ventilation hose (because my air filter housing was full or oil, and it was leaking out the air filter housing drain plugs).

4) Also, after the engine reaches normal operating temperature, and I turn the car off, there is a pressure release sound coming from the area around the exhaust manifolds. This hissing sound occurs every of couple of minutes, and stops after all the pressure (the manifold, or vacuum lines?) dissipates. Could this be related to the vacuum, or low compression problem, or could it be a blown head gasket?

5) One of the hoses leaving the charcoal canister is corked.

Any information would be greatly appreciated!!

i'm not completely sure, but your low power, bad idle when cold, low compression, and oil in the air filter most likely have to do with worn piston rings and valve seals. Hense the blow-by into he airfilter. You probably need a top-end rebuild. Not sure but that seems to make the most sense. Does it smoke when cold?
Ryan

__________________
83 300SD.......sold
96 integra SE....sold
99 a4 quattro....sold
2001 IS300.......sold
2002 330i.........current.
2004 highlander limited....current.

Normally, long distance diagnosis is difficult. In your case it isn't. Your engine is knackered. In case that is a UK word that doesn't translate, the engine is suffering from excessive wear.

I hope the great deal you got on the car leaves you enough cash to fund an engine rebuild, 'cos that's what you need. If you're lucky, the crank will be in good shape, but the cylinders/pistons certainly aren't.

There is a very, very slight chance that if the engine has been standing for a long time, the rings have seized in the grooves, but it sounds like all are affected equally, so this is unlikely.

In the UK you would have a reasonably strong legal case against the dealer.

Go into the classifieds section and ask around for a used engine for this car. It may be the only way to economically revive this car.

I suppose there was no warranty. If you feel like you were misled somehow by the dealer, take it back and see if there is sufficient goodwill to adjust the deal, or have them help you find a used engine for installation. Oftentimes dealers are willing to try to make good a fright pig like this car in order to avoid ill will.

Be firm and adamant about your demands, and make it clear that you are not just a crank and will be happy if they try to help.

Sorry about your situation.

Tom

__________________
CloudNine
'89 560SEC

sounds like the engine is worn out. If you believe in miracles and want to try something - you have a slim chance it could work. If the engine was sitting for a long time the rings could be stuck. For what it is worth - try running some engine flush in the crankcase to loosen up and desolve gummy deposits. Change the oil and add a quart of duralube when you do it. Drive the car about 400 miles and see if there is an improvement. My 560 sel sat for 4 years when I bought it and it burned oil 1 quart every 200 miles. I did the above and the rings came unstuck and I use 1 quart every 2000 miles now - I was lucky. If it doesn't work - the motor's toast anyway - might be worth a try - won't cost much.

Do any of you think the poor performance could somehow be related to the plugged vacuum line leading to the fuel distributor, or the warm-up regulator? The odometer indicates this car only has 128K miles. If this miliage is accurate , it seems unlikely that the engine would be completely shot. I want to make sure I have eliminated all possibilities before performing a rebuild.

Moedip:
According to the dealer, the car had been sitting for 6 months to a year before I bought it. The odometer, which is working at present, indicates the car only has 128K miles on it. It may be that the rings are stuck. I heard that engine flush can damage an engine, but if all else fails, I will give it a try. Thank you for the advice.

Tom:
Apparently, when I test drove the car, both times, the dealer had let the car idle before I got there, so the cold start problem wasn't apparent until I got home (200 miles away). He did disclose that the warm-up regulator might be faulty, but didn't say anything about the engine. I did anticipate spending some money on this car, since I purchased for only $1000. The dealer is located 200 miles from here, and I don't think he would be willing to help me out. Most everything else on the car is fine. Do you know of anywhere that sells M110 engines for around a grand?

Neil:
I have resources and contacts that would make rebuilding the engine a viable option. It's just a question of which would cost more: a low-mileage used engine, or new/machined piece parts (I'm trying to keep this under $1000)

Ryan:
Yes, there is a significant amount of white smoke that comes out of the car when the engine is cold. I guess this would be a sign of oil burning inside the crankcase?

I love to work on cars, I just haven't faced anything quite this challenging yet. I'm taking the proactive approach of gathering information from fellow Benz owners before trying anything myself (whose advice is greatly appreciated!)
The car seemed like a great deal at the time, but I am beginning to think it was a poor financial investment (although it will most likely be a great learning experience).
The problem is finding a reputable dealer that won't charge an arm and a leg.
According to my chilton manual, the first E-series appeared in 1977 with the 280E (123.033) followed by the 280CE (123.053) in 1978.
Thank you for the advice!

Correction: My chilton manual starts at 1975, so there may by previous E-series models.

Number of points.

Try freeing off the rings by pouring Redex or similar into the plug holes. Follow the instructions on the pack.

Ignore your performance issues until you get the compression sorted. Everything else is a detail.

The E in 280E is not a model designator. It stands for einsprintzung (I think that's how you spell it) which is German for injection. Mercedes did not use E as a model description until the W124.

All engines produce white smoke when cold. It is water vapour. Black smoke is fuel, blue smoke is oil, grey smoke is brake fluid.

Good luck. Remember this is a hobby car. If you can't afford the hobby, take up fishing.

Neil - very eloquently put !

__________________
1993 190E 2.0L (Euro.) sold
1991. 500 SEL (Euro.)
1991. 300 CE (Euro.) sold
1993. 500 E (U.S. spec.)