ATTS AAAARRRGGGHHH!

[hackish]

All I can say is run the hell away from an SH prelude that has the ATTS system. I was going to do a swap for a customer because his engine needed more power and was burning a little oil. So I obtained another H22A4 thinking the blocks were all the same. WRONG. So I ended up doing a complete rebuild and a complimentary P&P to keep the customer happy. I was also going to convert it to OBD1 and chip/tune it so he would have a little more power above the P&P job. WRONG! The ATTS unit will not work with a conversion harness. OBD1 ECUs don't have the necessary data communications lines from the ECU. There appears to be no way to keep the ATTS functions with a tuned ECU. The only possible thing I could think of that is an absolutely retarded amount of work would go like this... Replace all the OBD2 injectors and solenoids with resistors. Splice all the OBD1 sensors into the harness. Now run both the OBD1 and OBD2 ECUs with the OBD1 actually controlling fuel and the ignitor. As long as the OBD2 thinks it's controlling things I believe the ATTS box would work correctly. While this strategy may be successful it is likely to run into problems with the knock window being wrong since the OBD1 ECU is happily firing the sparkplugs when it likes and the OBD2 computer would hear noise before it thinks it should. Any ideas? -Michael

[Gaskleppie]

Just dont connect the sensor with the engine? Maybe when it hears nothing, it dont bothers..... I dont know...