JEEP GRAND CHEROKEE. 1996. 4.0L. 75K. Standard model with no modifications. As Petrol is about $8 a gallon over here decided to install a LPG system. Now I'm not expecting anyone to have any particular knowledge of my LPG system (but if anyone is interested it's a Stag300 from http://www.ac.com.pl/autogaz/en/stag300/ ) What I need to know is how to get a RPM signal for the LPG ECU. I've tried connecting to the coil and what I think is the crank case sensor but no joy. The only way I've been able to get any sort of signal that the LPG software will read is if I wrap the wire that comes from the LPG ECU around one of the HT leads (signal by induction, not a direct contact). The only problem with this is it's not steady enough and every time the signal drops, even for a millisecond, the engine flicks back to petrol. Had a conversation in a bar with someone about this and he thought I may be able to take a signal from the alternator but didn't know any more than that. Any sugestions would be much appreciated. :)