I've been playing around with my '82 TD lately. I thought the idle sounded a bit high (like 1000 RPM) so I decided to set it down to spec 830 RPM. My tach is not hooked up yet so I used my STI as a reference. The idle on it is 820 RPM so I adjusted the TD until the exhaust pulses felt about the same.

In the process, I reset the throttle cable, kickdown cable, and cold idle cable/adjustment. Now I believe there is some sort of deceleration fuel shutoff function built in to the VE pump. The diesel clatter disappears when I coast until the engine reaches a certain speed--then it comes back. There is also more engine braking available. It didn't do this before...

If all this is true, I expect fuel economy to be a few tenths of a MPG higher.

When I replaced the decel valve on my STI (K-Jet FI) I noticed a jump of 1-2 MPG. I'm thinking that I must do a lot of coasting (from high speed--hehehe).


One other concern... the car has always belched a cloud of black smoke whenever I leave a stoplight "spiritedly". As far as I know the injection timing is set correctly and my EGR system is not currently functional (the valve is closed). The injectors appear to be original. Right now I am running a strong additive through the fuel system in hopes of de-coking the injector nozzles and combustion chambers.

If the smoking persists, any ideas what it could be? There are some bench-vise marks on the hydraulic head of the pump which leaves me to believe that someone has rebuilt or resealed it in the past... I wonder if there are any internal adjustments in there that someone could have fu**ked for me...