trigger wheel runout?

[henry]

Hi
In need of some help. Have spent all day troubleshooting a MJ installation on a friend’s 4 cyl Land Rover. This was installed some time back by a company and apparently never ran correctly so they reverted to a standard dizzy set up, leaving the MJ stuff disconnected. I have to add I have the same set up which I installed myself on my Landy and it all works perfectly.
Symptoms are – it won’t rev! Idles fine with or without the MJ (and is 10deg advanced as per ‘limp home) – once the throttle is opened – if slowly revs will increase but it is reluctant and slutters on the way up and the advance increases - but jumps about a bit. Max revs not achievable. If the throttle is opened quickly (or blipped) it splutters and is even more reluctant to rev. Watching the display on the PC – Kpa dial goes right around clockwise (from 30 at idle) and the revs slowly rise. Display of advance bins shows it staying mainly to the bottom left quadrant of the display. I have substituted all components for known working ones and even swopped the MJ ecu onto my Landy – where it works perfectly. The only thing I have not been able to substitute is the wiring – which all checks out OK albeit a bit untidy!
So could it be the trigger wheel runout? It just seems that the EDIS is getting confused as to engine speed (have substituted the EDIS – same issue). The wheel has been bolted to the front of the pulley and if we get a gap on one side then rotate the crankshaft the teeth catch the sensor. Set a gap this side and the gap is probably out of spec – not huge and not measured but.....
So how much tolerance is there on this as I cannot think of anything else we can do. Did find several things wrong with the install – vac takeoff incorrect, some earth bonding not done, pin 4 not earthed (no switch to change maps installed – but will be) – all fixed but still same problem. It appears the MJ does not really know what advance to send to the EDIS – but both those units check out OK.
Any thoughts or help greatly appreciated – how done a search on here but cannot find quite these symptoms.
Cheers
Dave

[bmcdaniel]

Does the trigger wheel/sensor gap exceed .060" (1.5 mm) at any point? .040" (1 mm) is where it should be but I know of others that have run up to .060". The surface area of the teeth will affect that some, too.