Two questions

[Pritchard]

First off, I would like to thank everyone on this board for the helpful hints and ideas for keeping our 914's alive and kicking, and for providing me with some entertainment while at work.

I have a '74 2.0 L s/ stock engine except for electronic ignition.

I have two questions for the board:
1) What can happen to a CHT sensor, or ECU, that would cause me to have to place a resistor inline (Kjell Nelen article) to prevent "the lean hunt" at idle? (The engine will almost die from fuel starvation) The CHT is brand new and in the correct resistance range. I have done a quick visual inspection for loose/broken wires and found none.

2) After performing the odometer/trip meter repair as per the PP article, the milage on the odometer is increasing in sync with the trip meter tenth digit. (ie. mileage is increasing ten times as fast as it should) Anyone had this happen before? What should I do?

Thanks for your input.

Pritchard

[Dave Bell]

Concerning the CHT question.

The reason for the resistor in-line with the CHT sensor for "fixing" lean hunt is not necessarly due to any problem what so ever with the CHT sensor.

The lean hunt can be caused by a host of problem areas that leak air, or are mis- adjusted or are allowing to little gas at idle to get to the engine. The quick work around is to add some resistance in line with the CHT, (even a good CHT), to trick the FI brain into thinking the engine is colder than it is and thus prompting it to richen the mixture and thus curing your lean condition.

I put this "fix" into my 1.8L L-jet with the addition of making the resistance an adjustable potentiometer mounted on the dash.

It allowed me to richen up the mixture and keep the car running O.K. while I looked for the air leak / miss adjustments. I finally have everthing working pretty well now and the dash mounted pot serves as a nice "electronic choke". I richen the mixture up now only when I start up the car and turn it down after the car is warmed up so that it runs off of an un altered CHT signal when it is warmed up. When the outside temp is hot and I am running in the hills, I can dial the richness up again to make the engine run a little cooler.

- Dave