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Posted by: Porschef Feb 10 2012, 10:43 AM

Seems the last idle issue I'm having is that she'll start fine and idle at around 1400 rpm..then after a couple minutes drop below what should be normal, almost sounding like a she'll stall. If I get on the road or let her warm up a bit more, the idle is right where it should be. Can't seem to nail this one down. So my question is, has anyone tried using the available spacer tHat goes between the head and sender to slow down the heating up of the CHT to prolong a higher idle?

Thanks,

Joe

Posted by: vsg914 Feb 10 2012, 10:53 AM

Get one from Brad Mayer. They fool the ecu into a longer cold enrichment. Are you using the proper cht for your setup?

Posted by: 914Mels Feb 10 2012, 12:13 PM

The spacer might help you but after a couple of minutes of warm up, it is going to be transfering the heat pretty well. What outside temperatures are you having the problem in?

Posted by: ClayPerrine Feb 10 2012, 12:26 PM

The factory fix was a resistor added to the CHT circuit. It makes the mixture slightly richer during warmup, but not when it is running.

From the http://members.rennlist.com/pbanders/djetparts.htm....

"Non-Bosch, Wehrle part, 270 ohms. List price for this thing is nuts, >$20. Go to Radio Shack and buy a 1/4 or 1/2 watt resistor of near-equal value and a couple of crimp-on terminals for about $1 if you need this part."


Just put it between the CHT and the wire harness.

Posted by: Porschef Feb 10 2012, 01:47 PM

Sweet. Gentlemen, thanks for the replies. Just got back from a drive. It did the same thing from a not fully cold start, and so was idling a little rough when I started it, and then was fine after getting home 10 minutes later.

Winters been warm. It's 50* right now. The CHT sender is unknown to me, other than the car won't start when disconnected...

BTW, it's a 2056 w Ljet. I like it.

Joe

Posted by: Porschef Feb 10 2012, 01:56 PM

Interesting note... Clay, I checked out the link for djet, and I see that the fix for light backfiring during cold overrun was to richen the mixture with the knob on the ECU....being an Ljet setup, I'm curious as to how to rectify this, as it does this also. Perhaps the resistor?

My 2.0 djet was very idle tunable with that happy little knob...

Posted by: ClayPerrine Feb 10 2012, 03:27 PM

I would start with that resistor to fix the L-Jet cold running issue. I would also look into a set of 912E injectors. The 1.8L injectors are not really big enough for a 2056.

Posted by: Porschef Feb 10 2012, 03:49 PM

Clay, I just moseyed on down to the local radidio shak and picked up a 5 pack of 200 ohm resistors. Gonna give them a whirl.

The engine came with a set of 912e injectors. Part # 0 280 150 105. Unfortunately 3 of the 4 weren't working well/ at all so I sent them out to WitchHunter and they came back good as new.

Joe

Posted by: ClayPerrine Feb 11 2012, 07:59 AM

QUOTE(Porschef @ Feb 10 2012, 03:49 PM)

Posted by: Porschef Feb 11 2012, 08:21 AM

I have an inline FP gauge th at shows 29-30 lbs when running....that about right?

Posted by: sean_v8_914 Feb 11 2012, 09:54 AM

Clay:
have you done this or are your suggestions speculative based on info in this link?

Posted by: Porschef Feb 11 2012, 11:01 AM

After sitting overnight the CHT resistance is 4,670 ohms @ 37* F. That seems in the ballpark.

Posted by: jcd914 Feb 11 2012, 12:07 PM

Have you tried adjusting the fuel mixture using the misture adjustment screw on the Air Flow meter? It only really effects the mixture at idle , which sounds like what you need.
Also L-jet is very sensitive ti vacuum leaks, especially at idle.

Jim

Posted by: Porschef Feb 11 2012, 12:37 PM

Jim,

Yes I've messed with that. Its only the between initial startup ( say 30-45 seconds) and warm that's a problem. Seems like the spacer is the way to go, just gotta locate one.

Curt, do you have a contact for Brad?

Thanks,

Joe

Posted by: vsg914 Feb 11 2012, 01:24 PM

He's from Peoria Ill. Google will turn him up. I've got his info at my shop. Hes a member here too.

Posted by: rnellums Feb 11 2012, 05:32 PM

His email is p914ltd@yahoo.com

I'm driving my car to him tomorrow. A really straight reliable guy.

-Ross