Hi all, 1st time poster-just bought a nice 940 GL , great condition all over - 360,000 K's-my problem is: unless Gear shift lever is in the right spot, car won't start, have to up and down the range a couple of times- when I manage to jiggle it just right , starts up first turn over ???
Do I need to replace whole unit, or can bushes etc be replaced
Thanks for any help......

 

there's a starter interlock switch in the shift linkage to tell it its in N or P (if its an automatic) on an automatic, this switch is under the gear indicator right next to the shift lever, and I believe it also has the reverse light switch in it. to get at this switch, you've got to remove the console bezel (plate around the shifter, parking brake), disconnect the linkage under the car, and unbolt and lift the whole shift assembly out, THEN take it apart til you get to the switch.

here's the automatic shifter's part diagram... the switch is part 42...





if you've got a stick shift, I dunno if there's a starter interlock or not. they never sold very many manual transmissions in the US...

 

ok, i'm home and looking at the greenbook for a 1992 740/940. yes, thats the switch, it has a blue and pink wire that go to a 4 pin connector in the central console area, on the other side of the connector, it shows the pink wire is connected pin 4 to a white wire, which somewhere unspecified is connected to a pink wire again that goes to the 'start' terminal 50 on the ignition key. the blue wire from the shift switch goes to pin 1 to a bluegreen wire to pin 1 of the big block connector on the left A post then blue-green to pin 5 of an 8 pin connector at the left suspension tower to a blue-green wire to pin 50 on the starter.

the switch at the shifter has to be 'closed' for the starter to be connected to the ignition key. if you have a manual transmission, the 4 pin central console connector just has pins 1 and 4 jumped.

 

Hi Pierce, thanks for the prompt and insightful reply
I think the easiest route might be to replace the whole shifter unit with a low mileage from the wreckers

Or maybe , splice in a small 2 way rocker switch into the pink an blue wires coming out of the switch- would be a good engine immobiliser too !

 

Is the shifter very sloppy in putting it into gears? There are two plastic bushings on the linkage that connects the shifter to the transmission. For most of these cars by now these bushings are shot making the shifter very sloppy and not in the correct position for the starter interlock.

I'd check this first as I've had similar problems with both our 240s. Replacing the bushings for a few dollars tightened up the shifter and made the starting problems go away.

 

Yes the shifter is very sloppy, just discovered that if I jiggle shifter while cranking engine, can actually hear motor wanting to start or not, depending on jiggle position
will investigate getting those bushes replaced
Thanks very much

 

Hmm...

I was under the impression that the starter didn't crank unless you jiggled the shifter. If the starter cranks but the engine doesn't catch, then most likely it isn't an issue with the shift interlock. The shift interlock keeps the starter from even cranking if the shifter isn't in neutral or park.

 

Have discovered that instead of moving shifter up and down thru the range when it won't catch and start- if i apply slight pressure on shift lever , pulling lever towards rear of car - starts every time
Weird, but works for the time being

 

when you say 'catch and start', do you mean its turning over but not starting when its being funky? or do you mean its not cranking at all until you wiggle it?

its really hard to see how it crank and not start because of any issues with the transmission interlock, as that is ONLY wired to the starter motor itself, and not to the fuel injection or ignition systems.

 

Yes, it turns over , but doesnt catch - like if you have no fuel
But since I stumbled upon the idea of holding the shifter with slight rearward pressure, it starts 1st time every time

 

that transmission interlock switch has *NOTHING* to do with the fuel injection or ignition systems, its PURELY about disabling the starter motor if you're not in P or N. so... I dunno /what/ to think about this.

when the engine is running, if you put the shifter in "P" Park, does the engine feel like its dragging like its in gear? What about "N" Neutral ?