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1995 SL500 running bad after 10 minutes

804 views 6 replies 4 participants last post by  Ozzie Rob 
#1 ·
Hi all,
I have been having this problem for quite some time. Get in the car, fire it up, all good then drive a couple of kilometers, and it starts missing, and when I stop and try to go again, it barely moves.
Well, over the weekend, that is yesterday and the day before, I decided to try and fix the problem once again. I have put new plugs, competition leads, service with Mobil 1 oil as normal, new filters, checked vacuum lines, removed distributors and cleaned, along with rotor, new crank sensor, new fuel pressure regulator.

Yesterday, I decided to check the engine wiring harness, and it was pretty cactus, so I removed it, and went about re tapping each individual wire with a heat proof electrical tape, then taped them all together, not a bad job actually. I put everything back together, engine starts, runs pretty smooth, so I take my wife for a spin up to the shops, which is 2 kilometers away, almost there, and it starts to miss, and idle incredibly bad.

I turned the engine off when she went into the shop, and when she came out, fired it up again, and rough as, I could barely move. Ended up getting it home, parked it on the front lawn, and inside for a coffee. By this time I was cussing and cursing, as I have gone through I reckon every thread on here, and was amazed at the amount of people with the same problem, very frustrated, and an incredible amount of advice, even one guy that took his to a Benz dealer, that recommended someone who may specialize in these things (thought that was funny). Even though their Star Diagnostics picked different things up, after replacing all of these things, drive down the road, and same problem.

Well, I thought "F IT", and went back outside, and removed the engine covers, the panel that covers the computers, and the panel that covers the ignition control module. So, I am just standing there looking at it all, nothing really there that I haven't checked, then I started looking at the vacuum lines again, but as before, all good, so I'm staring at that ignition module, and just sort of following the vacuum line which, and I have to say, had no idea where it went to, but it looked like it went through the fire wall, and I'm just starring at this thing for about ten minutes, and have a real close look, and it was sort of aimed at the fire wall to give the impression that it actually went through, so I just touch it, and it is not going anywhere, just sitting there.

I thought you Fxxxcxxxxxxxxxxxx and start looking for where it actually connects, could not find a thing. So back inside Google up everything until I find a diagram of an engine with the vacuum lines etc. Spot where it goes, but when I go look I simply could not see anywhere for it to go.

Then, I put my arm down behind the engine, and under the manifold, and you got it, I grab a piece of plastic, run my hand down and hit rubber, so I pull it, and out comes a piece of rubber, with a piece of vacuum line in it.

I attacked my sons Audi for some vacuum line, and attached it, put everything back together, fire it up, smooth as, jump in, and headed back to the same shop, went through the same routine, and beautiful. I then drove home, but this time into the National Park, and when I hit the exit road, I hit the throttle, and smoked the tyres most of the way out, and I have275x35x18 wheels and tyres.
I thought I would tell my story, as the car runs like it just came out of the show room, and not anywhere did I find anyone mention checking that vacuum line even if it was broken under the manifold, you would not know.

Mission Accomplished Baby, We Have Lift Off.

Ozzie Rob
 
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#5 ·
Around THEBENZ, It certainly was a journey, and I have just returned from driving my son to work, about 120 Kilometers each way, and am still amazed at how well it is running.
I really believe that this particular vacuum line, if it were broken say, at the rubber under the manifold, you may put your hand under and feeling it is still in place, put a tick down as checked when in fact it is the problem.

Cheers, Rob
 
#6 ·
Hi Poundy,
Yes, you could literally throw a fortune at these things, but, I think the answer is check, and double, or even triple check, before you part with your hard earned. Also, iff someone can give me an idea on where to buy all the fittings that go on the wiring loom, like the one that goes on the oil pressure sender, then I will start making harnesses for cost of the fittings, quality wires, and postage, no more than $200.00.
Cheers,
Rob
 
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