Remedy for hackjob de-smog?

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Eta power
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Remedy for hackjob de-smog?

Post by Eta power »

Not directly E12 related, but close:

I bought a $350 Califorina 1979 633csi. Turns out someone got sick of all the smog crap and removed it all. They were heavy handed, though - the vacuum limiter is gone and the Jules Vern device is disconnected. The car runs surprisingly well, but, if you rev it and then left off the throttle, it bogs and sometimes dies. This is severe enough that the car is a bitch to move around the yard/driveway at low speed 'cause you need three feet: one to work the clutch, one to brake, and one to hold the throttle open so it doesn't die. Seems to have good torque, though, I got it chirp into second.

I figure my options go like this:

Somehow, someway, figure out how to patch the L-Jet system back together.

Mortonic 1.3 for fuel only.

Megasquirt 1 for fuel only.

I'm really tempted to Megasquirt the car, but I wanted to see if there was an easy way to get L-Jet to work before I take the plunge.
-AJ
1986 528e | 1980 320i | 1972 240z
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CabbageFumes
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Post by CabbageFumes »

Explain how you can use M1.3 for fuel only.
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Mike W.
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Post by Mike W. »

Hey AJ, good to see you here!

Any of those things would be options, I'd probably retain L jet but I've got lots of parts. M1.3 would probably be the easiest and either retain full ignition control or simply use Motronic spark controls going thru the conventional distributor. Timing would have to be relatively close, but not perfect. Disconnecting the AAV? That's nuts, it's not even smog, it's a warm up device. Big question from here is do you have to deal with smog?
CabbageFumes wrote:Explain how you can use M1.3 for fuel only.
Easy, while it incorporates it, you don't have to use that component of it, just don't connect the lead that would go to the coil.
Mike W.



1980 528i, 3.5 euro, 5 speed conversion
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1998 328is, quick and efficient, but not satisfying
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CabbageFumes
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Post by CabbageFumes »

He said he wanted M1.3 for fuel only, not spark.
Spoiler alert: You can't use M1.3 for fuel only.
You need references from both the crank and #6 spark plug wire to fire the injectors, which IS spark(ignition). You would want two DMEs, two harnesses in the engine compartment, etc?
Why would you? It doesn't make sense.
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Post by T.Hanson »

http://www.malloc.nl/BMW/635CSi/pages/en/index.html

How many years, hours of hands on learning experience between Mike and Cabbage ? Makes me dizzy.
Eta power
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Post by Eta power »

Looks like I'm gonna have to get some vacuum hoses and hook the ICV back up and see if that fixes it. Would it be possible to get by without a vacuum limiter?

I will admit that I do not have any hands-on experience with Motronic 1.3, but since the resident expert says it needs the inductive pickup, it must be so. Anyway, I don't know why I couldn't just make something work using the #6 spark plug wire off the donor car, but I digress. I like the idea of Megasquirt better, anyway.
-AJ
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CabbageFumes
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Post by CabbageFumes »

It requires both the engine speed and the cylinder number to time the injector firing. It's a closed system. keeping the l-jet manifold limits you in upgrades unless you are open to fabricating stuff to make 1.3 parts fit. If you want to commit to converting to megasquirt, you can keep your original low z injectors and get rid of all the smog stuff. It's your best option in the long run. You'll still need the front trigger wheel and pickup from the 1.3 for megasquirt though...
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Post by Mike W. »

Eta power wrote:Looks like I'm gonna have to get some vacuum hoses and hook the ICV back up and see if that fixes it. Would it be possible to get by without a vacuum limiter?

I will admit that I do not have any hands-on experience with Motronic 1.3, but since the resident expert says it needs the inductive pickup, it must be so. Anyway, I don't know why I couldn't just make something work using the #6 spark plug wire off the donor car, but I digress. I like the idea of Megasquirt better, anyway.
It's not a ICV, but an Aux air valve. A warm up device, not an idle control. Many have had problems with the water based one but I like them better than the later type that lives on top of the valve cover.

As far as needing the inductive pickup, I've heard not, that it reverts to batch fire without it, but no personal experience. Regardless, you could still put it in there and use it for fueling only. Lots and lots on M1.3 on Mye28, you're there already, read up on it there.
Mike W.



1980 528i, 3.5 euro, 5 speed conversion
1981 528i, 3.6, Recaros and more. Project
1998 328is, quick and efficient, but not satisfying
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Falkenberg
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Post by Falkenberg »

CabbageFumes wrote:He said he wanted M1.3 for fuel only, not spark.
Spoiler alert: You can't use M1.3 for fuel only.
You need references from both the crank and #6 spark plug wire to fire the injectors, which IS spark(ignition). You would want two DMEs, two harnesses in the engine compartment, etc?
Why would you? It doesn't make sense.
If I would be combining, I'd take the gamble and use the #6 motronic spark wire from the classic mechanical dizzy as input for motronic. Just out of curiosity. And trying not to swap heads / cam or fitting hard-to-get dizzy conversion components.
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CabbageFumes
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Post by CabbageFumes »

Falkenberg wrote:
CabbageFumes wrote:He said he wanted M1.3 for fuel only, not spark.
Spoiler alert: You can't use M1.3 for fuel only.
You need references from both the crank and #6 spark plug wire to fire the injectors, which IS spark(ignition). You would want two DMEs, two harnesses in the engine compartment, etc?
Why would you? It doesn't make sense.
If I would be combining, I'd take the gamble and use the #6 motronic spark wire from the classic mechanical dizzy as input for motronic. Just out of curiosity. And trying not to swap heads / cam or fitting hard-to-get dizzy conversion components.
Another spoiler: The crank trigger is mandatory for M1.3 to do anything. The system will work with crank trigger alone, but not well. (in reference to the comment mike made earlier, it won't convert to batch fire, because it was always batch fired.) As far as the plug wire trigger goes, getting a pulse from one out of six spark plug wires isn't enough information to control anything on its own.
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Post by Falkenberg »

That part was so obvious that I did not even mention it :)
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Post by CabbageFumes »

Falkenberg wrote:That part was so obvious that I did not even mention it :)
True, but it looks like it needed to be said because there have been comments made that sound like there is some confusion about how Moronic 1.3 works. :wink:
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Post by Eta power »

Got rid of the wrecked euro E28 520i last weekend, so I had time to work on the six this week. Installed a new-used outer thermostat housing to replace the one that had the bleeder screw broken off in it. Found out the car didn't have a thermostat. WTF?!? :x Good thing a I decided to buy a new thermostat "because I'm in there".

Anyway, I decided that I was sick and tired of putting up with the way the car has been running and just hacked up the IACV circuit with some spare 5/8" heater hose. Yeah, I know. Anyway, the car actually idles on its own now. Took it for a quick spin to the local gas station and it drives quite nice. Think I'm gonna install some new fuel hoses and start driving it more, I want to see what it's like getting on the freeway with an M30. :lol:

Thanks, guys!
-AJ
1986 528e | 1980 320i | 1972 240z
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