Five-Speed Conversion, Update and Questions

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BradInTexas
Posts: 41
Joined: Tue Jan 06, 2009 10:25 am
Location: Weatherford, Texas

Five-Speed Conversion, Update and Questions

Post by BradInTexas »

Five speed conversion went pretty well. At first the car wouldn't start but then I remembered you have to be in "Park" so I shorted the connector where the plug when into the old auto shift handle and viola! The car was running poorly, but after replacing two injectors I finally got it running on all six. The engine I put in with the trans is pretty tired, with low compression on two cylinders. It would not rev out at all, but thanks to Peter's throttle FAQ I discovered the WOT switch was not working. It still has a flat spot at 3000rpm, but runs OK otherwise. I'll get to the AFM next.

The problem for now is I have no back-up lamps, and the inspection will expire at the end of the month. If anyone has done the auto to manual thing and can give a hint I'd appreciate it. I thought I had connected everything properly, but obviously I missed something (like I discovered with the no-start condition described above). Thanks.
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1st 5er
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Joined: Sat Jan 10, 2009 10:43 pm
Location: Cypress, Texas
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Post by 1st 5er »

May be a conversion in my future, so I'll watch and learn.
Sherman

TexFest LSB&F V

95 525iT (Her DD)
92 ///M5 (????)
91 ///M5 (T donor)
88 ///M5 (Das Beast)
86 535i (Snob)
79 528i (1st 5er)
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jbbush
Posts: 24
Joined: Mon Feb 02, 2009 11:19 am

Post by jbbush »

What wires did you bridge? I'm removing that wiring harness while I have the dashboard out in (sort of) prep for a manual-transmission conversion later on.

Thanks!
Jonathan
1985 323i Baur
http://www.totallythatstupid.com
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Mike W.
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Location: Sonoma County

Post by Mike W. »

The A/T wiring plug by the shifter is where you need to tie in. It's more or less square with maybe 9 terminal positions. IIRC it's blue/white and green/white that you need to hook up to the reverse switch in the tranny, but look on the diagram, don't take my word. And a word on that, they are often bad especially after sitting for a long time, so you might need to replace that switch too.
Mike W.



02 525ita. Wife's, aka grocery getter
02 530i. New to the fleet, 3 pedals.
03 QX4, AKA the Datsun. Finally got the 4WD vacationmoble to stop smoking.
07 Xterra. Still on the DL, a purchase from hell.
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jbbush
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Joined: Mon Feb 02, 2009 11:19 am

Post by jbbush »

Oh, I had totally forgotten about the reverse light circuit! Good to know. Maybe I should leave that harness in the car.

I was actually talking about either bypassing or bridging the wires in that harness so the car will think it's always in Park or Neutral and thus start.

Thanks again.
Jonathan
1985 323i Baur
http://www.totallythatstupid.com
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jbbush
Posts: 24
Joined: Mon Feb 02, 2009 11:19 am

Post by jbbush »

And here's an interesting data point:

On RealOEM the part number for the automatic and manual pedal brackets is the same. In the diagram, it shows one pedal bracket for both and parts and part numbers for a cover plate that goes over the clutch master cylinder holes when used in auto trans cars.

Only, on my late-production 528iA, I don't have any holes or any cover plates on my pedal bracket; it's all solid! This is going to make the manual transmission conversion a little more, um, interesting. Hello, hole saw.
Jonathan
1985 323i Baur
http://www.totallythatstupid.com
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