Hello,

I ran across a note that's listed in the Mercedes CD W124 Volume 1 Under Comlaints/programmed repairs.

This note in effect says that you can glean another 50 rpm out the CIS by splitting a wire that runs from the Starterlock switch to the CIS, and connect the CIS end to ground.[ I think they mean +ve 12 volts though].
Normally in the start mode this circuit would provide +12 volts to the CIS.

My question is anybody tried this??

I could really use another 50 rpm on my 300ce.

Brian:

It worked well on my 89 TE. Here's where you find the wire.

http://www.peachparts.com/shopforum/showthread.php?t=134810

__________________
Fourings

84 Audi Coupe GT with Turbo engine, EFI (buh-bye CIS), Jamex seats, Koni's/H&R's, e-code lights. 210k and counting.
1992 Anthracite 400E, 161k, "Grey Ghost".
1986 VW Quantum Syncro, 192k, gone to the crusher in the sky.
1989 300TE 172k. (Was mine, now also Mom's car)
72 280SE 4.5 (Mom's car)

Fouring,

thanks for the reply

Are you sure its a ground [chassis ground] thats required.

If you look at the wiring diagram, it shows that this pin #50, at the CIS, is given +ve 12volts when starting.

I want to be sure because we dealing with CIS input, hate to blow the thing up?? The Mercedes manual does say ground at the CIS.

Please advise.

Brian

We have gotten our info from different places as far as the fix goes, so I haven't actually found this wire in the wiring diagram, and as you can see in the old posting I didn't know where to find the connector until I was directed by ILUVMILS so I couldn't tell you which wire I grounded, just that I grounded the one with the male (it was male right?) end. I followed the directions given to me in that posting and it worked. I didn't want to blow anything up either, which is why I was asking about which end to ground.
You now know as much about this as I. After grounding this wire my idle went up and I found other things to scrape my knuckles on.

__________________
Fourings

84 Audi Coupe GT with Turbo engine, EFI (buh-bye CIS), Jamex seats, Koni's/H&R's, e-code lights. 210k and counting.
1992 Anthracite 400E, 161k, "Grey Ghost".
1986 VW Quantum Syncro, 192k, gone to the crusher in the sky.
1989 300TE 172k. (Was mine, now also Mom's car)
72 280SE 4.5 (Mom's car)

Fourings,

Thanks again for your reply.

The wire in questions is clearly shown in the the wiring diagram, and it also shows which end you would need to ground. If you ground the wrong end you will have a dead short to battery when you move the ignition switch to start.

This wire goes from the ignition switch [start position] to the CIS pin #50 via the X26 plug located under the fuse box, and is colored Violet.

My questions was " Did you actually ground it, That is to chassis"

Sorry to repeat the question, I just want to be sure.

Thanks

Brian

PS: There was another mod that places a resisitor in the temp sensor circuit. Are you familar with that one?

Not familiar with that one.

__________________
Fourings

84 Audi Coupe GT with Turbo engine, EFI (buh-bye CIS), Jamex seats, Koni's/H&R's, e-code lights. 210k and counting.
1992 Anthracite 400E, 161k, "Grey Ghost".
1986 VW Quantum Syncro, 192k, gone to the crusher in the sky.
1989 300TE 172k. (Was mine, now also Mom's car)
72 280SE 4.5 (Mom's car)