Hi guys,

I've been trying to get my trip computer to read and record fuel consumption accurately with my V8 XJ6. I read the write-up on jag-lovers, but I haven't gotten an answer that works yet.

The ICU in the trunk, which gets it's feed from one of the LT1's injectors has been verified that it is sending information to the trip computer. However, this information is very wrong.

I modified the ICU by replacing one of the yellow capacitors with two 104k 250v mylar capcitors running in parallel in place of the yellow one that was desoldered from the board.

This was done to change the hz so that it would record the LT1 pulses correctly and feed that information back to the trip computer.

in INST mode, i get anywhere from 5 (at idle) to 161 and higher when driving around. The AVG is way too high for a v8 -- it is claiming i am getting 28+ mpg (not possible). The FUEL button reads a steady 0.0. So there is definitely something amiss.

Has anyone on this board successfully modified their ICU to work with the GM system?