luvthelake2007
New Member
Fuses ok, installed new coil, ran resistance on MPEM ...within values except Tan/Black to black was 91 when value less 200 and black/red to black was 11.8 when value suppose be less 10 ohms; got no resistance shown at all on red to red and red to red/purple when value suppose to be greater than 1 ohm. Manual shows Verification for Trigger Coil for 787 & 987 engines, but not the 717. Also says due to integrated CDI module, it is not possible to take any resistance measurements. What additional tests can tell me if problem is the pick up coil? or MPEM? Bad wiring/harness… my manual says Generating coil Black to Red/Black resistance should be 40-76 ohms. Was reading "zero" ...took off the coil, cleaned the grounding wire, got a "56" reading...when put back on and turned over engine, got 7 or eight "sparks" from plug, then NO SPARK at all from either plug. For three months before this problem, the horn was hit & miss with "beeps"...sometimes got 2 beeps whenn plugged in ...sometime none; however, even with no beeps, 'Doo would still start and run fine. Would this have anything to do with MPEM not reading to give spark. The Black/Red wire, when turning over engine registers 19-21 volts. Anyone think the module is problem? Any other tests before ordering this expensive part...have already wasted $$$$ on ignition coil I did not need. Thanks!.
