Rover 3.5 that wont start

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Grizzly
Posts: 3
Joined: Thu Mar 31, 2011 4:31 pm
Location: Mullingar Ireland

Rover 3.5 that wont start

Post by Grizzly »

Hi, I have fitted a MJLJ to my 3.5 Rover which refuses to start in limp home mode, I have checked the wiring and rechecked the wiring and cant see anything in the wrong place. I have 12v to the edis unit. I have set the crank sensor at .5 mm from the trigger wheel and I have checked the sensor trigger wheel position and it appears to be correct. Any help would be appreciated

Spockie-Tech
Posts: 152
Joined: Wed Jan 02, 2008 12:52 pm
Location: Melbourne, Australia

Post by Spockie-Tech »

Have you tried reversing the wires from the VR sensor to the EDIS ? People commonly get them backwards. Usually if you do, it kicks a little now and then on cranking, but wont run.. but they can also fail to kick at all.

Have you verified that you also have 12v power to the coilpack ? measuring from the common + coilpack terminal to battery -.

The negative side of the coilpack is switched by the edis so you can't measure the voltage from positive to it.

All The EDIS needs to work in limp home mode is power to the EDIS and Coilpack, the VR sensor signal and the correct coilpack wiring

Grizzly
Posts: 3
Joined: Thu Mar 31, 2011 4:31 pm
Location: Mullingar Ireland

Post by Grizzly »

Hi Spooky Tech, i have 12v at the coil packs and at the Edis unit, I tried reversing the polarity on the sensor and also checked the voltage between pins 5,6, on the edis unit about .25v when cranking. I tried another crank sensor same result. The engine does fire occasionaly and backfires through the carb.

Spockie-Tech
Posts: 152
Joined: Wed Jan 02, 2008 12:52 pm
Location: Melbourne, Australia

Post by Spockie-Tech »

OK, So it can send sparks to the plugs then.. Thats a beginning.. :)

Have you confirmed you have your spark plug wiring correct to suit your firing order ?
I'm assuming your Rover 3.5 is the english V8 ? (Im from Australia, and theyre not common down here)

If so, your firing order should be 1-8-4-3-6-5-7-2 (check it for sure yourself, since Im just going of what I found on the net and your engine might be different for some reason)

so, you arrange the order like this for the coilpack plug wiring.
1-8-4-3
6-5-7-2

So
Plugs 1 and 6 connect to coilpack A
Plugs 8 and 5 connect to coilpack B
Plugs 4 and 7 connect to coilpack C
Plugs 3 and 2 connect to coilpack D

Make sure the A-B-C-D wiring from the EDIS to the coilpack corresponds to the coil that you have those cylinders connected to - so the "A" wire goes to the coilpack that is connected to 1 and 6 and so on.

If all that seems correct, have a closer look at your VR sensor.
Aligned properly with the teeth (not off to one side) ?
Trigger Wheel Missing-tooth notch aligned correctly in relation to top-dead-center #1 ?
If this is your first EDIS conversion, make sure you read and understand the bit about getting the notch in the right place
Gap between sensor and teeth correct ? (about a credit card thickness will usually do it)
No run-out, or wobbles in your trigger wheel caasing a variable gap ?
VR sensor mounted on a solid bracket that cant flex about easiy ?
The wire from your VR sensor to the EDIS isnt too close to any sources of interference ? Spark Plug Leads, Alternator etc ?

Check the voltages on the EDIS and Coilpack *while cranking* and make sure they arent sagging too low (minimum 9 or 10v, more would be better)

Are you using resistor spark plugs (usually have an "R" in the park number somewhere) ?
Some people have experienced problems with non-resistor type plugs, although I havent personally.

Thats about all I can think of off the top of my head at the moment.
EDIS's are really simple once you get your head around the basics..
Give them Power, correct wiring, and a good VR signal and off they go.

Double check all that, and let us know how you go.

Grizzly
Posts: 3
Joined: Thu Mar 31, 2011 4:31 pm
Location: Mullingar Ireland

Post by Grizzly »

happy days it runs :lol: I had the gap tooth onthe wrong side of the crank sensor :oops: all I have to do now is to programe in a map :roll: thanks for the help, Ill be back!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

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