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Porschef
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
TheCabinetmaker
Get one from Brad Mayer. They fool the ecu into a longer cold enrichment. Are you using the proper cht for your setup?
914Mels
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?
ClayPerrine
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 D-Jet Info Page....

"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.
Porschef
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... huh.gif

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

Joe
Porschef
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...
ClayPerrine
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.

Porschef
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
ClayPerrine
QUOTE(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



If that is the case, then switch the fuel pressure regulator out for a D-Jet one. Use it to up the fuel pressure to richen the mixture. Don't play with the insides of the air flow meter, they are calibrated for a specific spring tension, and it is easy to mess up.

Porschef
I have an inline FP gauge th at shows 29-30 lbs when running....that about right?
sean_v8_914
Clay:
have you done this or are your suggestions speculative based on info in this link?
Porschef
After sitting overnight the CHT resistance is 4,670 ohms @ 37* F. That seems in the ballpark.
jcd914
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
Porschef
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
TheCabinetmaker
He's from Peoria Ill. Google will turn him up. I've got his info at my shop. Hes a member here too.
rnellums
His email is p914ltd@yahoo.com

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

-Ross
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