Dan

I thought the same. I had taken mine to a number of MB specialists how suggested that I throw a bunch of parts at this car because they were so puzzled at what was going on. I eventually found a guy who knew D-Jet pretty well and was willing to take his time. He had the car for about two weeks and through the whole car testing and setting everything up correctly. He said he had it running perfectly one day and then suddenly it started to run super rich out of the blue. No adjustments were made or anything else prior. This is when he suspected the computer.

We changed it out and has run fine since.

__________________
With best regards

Al

FYI there is a D-Jet EFI computer listed on Ebay as we speak. It's a little price at $199. The last one I sold on Ebay went for $70. You could reach out to him and see if he is willing to deal.

__________________
With best regards

Al

Good morning,

Many thanks for your suggestions!
Tom:
It seems as if I will need to gain access to a gas analyzer in order to properly gauge the mixture and verify the settings on the ECU.
The Throttle valve switch thought is also intriguing, I will see if I can check that out.

Mark:
Yes, the short trips are certainly complicating the situation. However, we have had the car for three years, and up until recently, this has not been a problem. I'm sure something must be amiss!

alabbasi:
Thanks for the tip, I will watch this and see if I can snag a deal. And then cross my fingers to see if it's in any better shape than the one I've got!

__________________
Dan Davis
74 450 SLC
59 Jaguar (Mark 1)

On the gas analyzer note, my Mechanic set mine up by taking it to a shop that has an emissions machine and tested it there.

You can buy a Gunson Gas Analyzer for around $100 on eBay but I have no idea what they are like.

__________________
With best regards

Al

I know nothing of these systems but I would like to respectfully suggest that you run the engine as little as possible until you fix the problem. Even a slight amount of fuel in the oil can drastically lower the viscosity. I heard a mechanic quote a study that said 1 teaspoon of gasoline in 5 quarts of 30W oil would render it a 10W oil. Don't know how true this is (sounds extreme) but it's worth taking into account for your engine's sake.
Chuck.

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1983 M-B 240D-Gone too.
1976 M-B 300D-Departed.

"Good" is the worst enemy of "Great".

Thanks cjlipps,

This is good advice, but you know how it is with the wifes car
I am draining and replaceing the oil weekly until I find the issue.
It's cheap insurance, and keeps her on my good side!

__________________
Dan Davis
74 450 SLC
59 Jaguar (Mark 1)

Good Morning!

Another week in diagnosis...
Saturday's oil check showed no increase in the oil level.
However, there really isn't anything that I did last week that would lead me to believe that I had "Fixed" the problem.

This Saturday, I replaced all of the vacuum lines.
I found the line to the distributor was shot, which disabled the retard.
Other lines were marginal as well, which got replaced.

I also tested the Water Temperature sensor, by shorting it to ground with the engine running. I did not get an increase in engine speed as the book suggested. The motor was warm, and I'm not sure that it should have increased in that condition.

I tested the action of the diaphragm on the Pressure Sensor, it appeared to work properly without leaks, and the hose connection was good as well.

I tested the Throttle Switch by reading the ohm values between pins 12 and 17, and it read .05 as it should with the throttle plate closed. I also counted 20 clicks as I moved from closed to WOT.

I then set the fuel rail pressure from where I found it at 22PSI to 28 PSI.
As I did this, I noticed the gauge read stable at 22, but shook a good a good deal as I got to 28. Is that a sign of something?

At that point I buttoned it up, and took it for a spin. It seems to be running fine.

My wife used the car to go shopping without any issues. And then my Son took it out that night.

He called an hour later to tell me that the car quit at a stop light, and it took him 2 or 3 minutes to get it going again.

I am now wondering if there is an intermittent issue with a sensor, or in the ECU which would cause it to run richer than it should.
Could it be the Water Temperature sensor?

I expect to see more gas in the oil somewhere down the line.

Many thanks in advance for thoughts on the subject.

__________________
Dan Davis
74 450 SLC
59 Jaguar (Mark 1)

A month has gone by since my last report, and it's time for an update.

The oil level has remained constant, and there have been no issues with gas in the oil. This would seem to be good news, but I am still wrestling with the root cause of the issue, because I didn't really change or fix anything since the last time it happened.

Well, there is one thing.....

When I last drained the oil, I filled it to the halfway point between the detents on the dipstick. Previously, I had it much closer to the full mark.

I am now beginning to believe that the dipstick may be marked incorrectly, or at some point may have been replaced by an incorrect one.
The overfilling of oil, may have caused the issue.

Does anyone have correct measurements for the dipstick?

74 450 SLC.

Many thanks!
Dan Davis

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Dan Davis
74 450 SLC
59 Jaguar (Mark 1)

Dan

Go to http://www.w116.org

They have an M117 engine manual on that site that will have this info.

All the best

Al

__________________
With best regards

Al

If you're getting gas in your oil, and you are only siphoning off the excess, you are still running a very diluted oil.

This can make short work of your bearings, make sure the oil is oil and not oil+gasolene!

Jim

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14 E250 BlueTEC black. 45k miles
95 E320 Cabriolet Emerald green 66k miles
94 E320 Cabriolet Emerald green 152k miles
85 300TD 4 spd man, euro bumpers and lights, 15" Pentas dark blue 274k miles

Thanks Jim,

Yes, I was draining and refilling for a while there.
But all is stable at least for now.

Many thanks!
Dan

__________________
Dan Davis
74 450 SLC
59 Jaguar (Mark 1)