Testing and Clearing Injectors

Mark Harnden 86 XJ6 engine turns over, has spark but won't start.

Mark, I had a similar problem with my 85 XJ6. The car had been sitting for a long time while I rebuilt the engine. When I put it back in the car and hooked everything up, it wouldn't start. Had 35 lbs of of fuel pressure at the rail, spark that would singe the hair of a donkeys tail 50 yards away but it wouldn't start. Also no fuel smell after spinning it over numerous times. Turned out I had 4 injectors clogged, only two were spraying fuel. I rigged a neat little gadget with a flashlight and an old injector plug off another engine. 2.5 to 3 volts will open the injector, so I wired the plug with about 6 inches of lead to the tail end of the flashlight and hooked it up to the light switch. When you turn on the flashlight you get 3 volts at the plug. I pulled my injectors(still hooked to the fuel rail) pressurized the system and then hooked my little gadget to each injector the ones that were stuck did nothing, the ones that were good sprayed a nice stream of fuel. I removed and cleaned the stuck ones with carb cleaner, flushing it through the the injector with 30 psi air pressure, opening and closing them with my Gadget till they flowed free. Took about 40 minutes to do the job and saved me a bunch of $$$$$$. As soon as I started turning the engine over with clean injectors you could smell the fuel right away. Engine started and has been running great ever since. I've got about 250 miles on it so far. Hope this helps.