Having hot idle problems and need to check the old CHT. It is also bogging on take off unlees it is revved. My first thought was vapor lock but thought I would check/replace the CHT first.
Thanks,

John

The resistance of the CHT falls as the engine heats up, so measure it cold, then measure it hot. It should be under 200 ohms hot, and over 1700 ohms cold. See Brad Ander's site for a complete troubleshooting guide for D-Jet: Anders' site

I bought one of these sensors new once, and it was faulty, but I did not know it was the problem until I did this little test on it...Put the sensor in the freezer, for 15 minutes or so, that will give you the highest resistance. Take that measurement, then wire the sensor directly to the tip of a soldering iron, and re-attch your leads to the sensor wires. Watch it make its changes across the scale after the soldering iron is plugged in. This will show you how the sensor changes resistance value to tell the ECU the head temp. The value will change (lessen), which should be smooth, no quick, or eratic spikes. The one I bought new would actually spike to infinity, while heating up, which 3x richens the mixture, and kills the engine. The car left me stranded several times. As I mentioned, the sensor was new. Knowing how/if the sensor is functioning is half the battle. You can then unplug the iron, and watch the value return to a mid range number. This problem you are having might not be CHT sensor related. Normally when they fail, the car will not run at all. Check the part number on it, if it is mis-matched...then that is a major problem with drive-ability. Brad Anders site is one of the best tools you have on your side to troubleshoot the D-Jet system. I am currently working on a 70 1.7 that has the same problem you are having, and I have not yet solved it. Parts on order to coorect all vacuum leaks at the moment.

Martin

QUOTE (flyloki @ Aug 9 2005, 11:30 AM)

Having hot idle problems and need to check the old CHT. It is also bogging on take off unlees it is revved. My first thought was vapor lock but thought I would check/replace the CHT first. Thanks, John

Also check your timing and that the advance is working. Sometimes a dirty sticking advance plate will cause these systoms.

Yep, read Brad Anders site until your eyes go all blurry.....

Thanks for the input guys...Brad Anders site is very helpful. I have a new and known correct part # CHT on order and I'll check it before installing. Looks like the gasket/ rubber sealing boot between air cleaner and throttle body has disentigrated (that must be the giant sucking sound Perot was referring to); apart from sucking sand etc. into the motor, could this affect hot idle and hot bogging during take off.