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Do you need my address, so you can ship me your car, and have all the parts drop-shipped? I'll make the time.
:p
Maybe do your sister/BIL's car first??:p What happened?

For anyone with a Djet, who really wants to abandon the original Bosch system, Barri on Peachparts did a MS conversion a few years back. He documented it here:

Converting a 1974 450sl to Megasquirt

Well worth reading. Then go and read the rest of the stuff on the net - there is a lot of it. This a good place to start: DIYAutoTune.com Megasquirt Kits / Assembled Engine Management Systems, Wideband o2 Sensor Systems and tuning products

As Daryn said, be prepared to spend a lot of time on tuning. Not many have done DJet MBs, so you could be on your own.

One problem I see, is that many are striving for fuel efficiency. But, our old V-8s were designed to run rich. Some old mechanics warn not to try and run close to Stoichiometric. Could damage the engine.

After researching MS, I decide to instead try and get my D-Jetronic system to run as it should. The addition of a full time open loop Wideband O2 sensor and AFR gauge really helped. If you don't know what the mixture is on a Djet, you are dead in the water. Same is true for MS.

Only reason I would go to MS, would be if I needed a new ECU or MPS and neither of these could be obtained new or used. Others however, find it a neat project, so go for it if you like that sort of thing!
 

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Graham,

What all did you have to do to install the gauge and sensor? I know about the need to install a bung in the exhaust, but did you only install one sensor? If so, where and which type; heated or not?

I've considered this as a tuning aid / monitor, but have had to 'back burner' it due to some other things coming up. I'd like to get an idea of where I have to go before I start out.

Thanks,
Scott
 

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I thought that more than a few of his solutions were fn brill.

And very budget conscious.
I 2nd that.

I had been reading an article in the december Hot rod magazine about a system called EZ EFI from FAST that is self calibrating and self tuning. It is a real interesting system using all Gm parts. It requires a holly flange but I was thinking it might make a cool experiment one of these days.
 

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Graham,

What all did you have to do to install the gauge and sensor? I know about the need to install a bung in the exhaust, but did you only install one sensor? If so, where and which type; heated or not?

I've considered this as a tuning aid / monitor, but have had to 'back burner' it due to some other things coming up. I'd like to get an idea of where I have to go before I start out.

Thanks,
Scott
Scott,

I bought an AEM wideband AFR gauge. (About $200 on eBay). It comes with it's own specific O2 sensor - all wideband sensors are heated, I believe. I had an exhaust shop weld in a bung for me ($50) Choosing where to put it was a dilemma, so I put it after the crossover just before the center muffler. I figured there would be some mixing by then.
I drilled a hole through the tunnel under back of console to bring the cable through.
Some pics:
 

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Discussion Starter #26
Hi,

Finally had my car diagnosed, bad ECU. After riding the car for some time at high speed, at hot temperatures (now it is +39C), ECU start to send wrong signals. Bought one from Ebay, does anyone has the instructions how to replace it?
 

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Hi,

Finally had my car diagnosed, bad ECU. After riding the car for some time at high speed, at hot temperatures (now it is +39C), ECU start to send wrong signals. Bought one from Ebay, does anyone has the instructions how to replace it?
Sometimes problem is not ECU, but various sensors or other electric/electronic parts that supply ECU with signals. I have never known any way of actually checking an ECU other than swapping it for a known good one.

To change ECU, first find it under dash (passenger side). You may have to girst remove a cardboard cover held in place by a series of plastic fasteners just to right of fuse box). ECU has a clip that holds it in place - loosen clip, then just pull old one out. When out, cable (like an old style parrallel printer cable) will still be connected. Disconnect and the reverse procedure to install - You will see iot has a rubber locating grommet - once that is in proper place, just reclip.
 

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MBGraham, this is an old thread so I hope you see this.

Below you say you routed the from the O2 sensor in to the car through the hole in the pics below. That looks like it is right in front of the passenger seat. So why that spot for the hole? How did you get the cable from there to the meter mounted in the center console? Also, do you worry about the hole you drilled in the tunnel wall rusting?


Scott,

I bought an AEM wideband AFR gauge. (About $200 on eBay). It comes with it's own specific O2 sensor - all wideband sensors are heated, I believe. I had an exhaust shop weld in a bung for me ($50) Choosing where to put it was a dilemma, so I put it after the crossover just before the center muffler. I figured there would be some mixing by then.
I drilled a hole through the tunnel under back of console to bring the cable through.
Some pics:
 
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