Starts When the Shift Lever is Placed in Park or Neutral

[TomC]

Hi Group
3.0Cs with an automatic transmission. This car will start if the shift lever is placed in park or neutral. No need to turn the key to the start position. If the shift lever is in one of the other positions the car can be started by turning the key to the start position. If the car is running and the shift lever is put in park or neutral the starter will try to start the engine.
My guess for a lack of a good one is the starter relay (automatic transmission). Does anyone know were this relay is located?
TomC in Ohio

 

[HB Chris]

Top of brake booster tube I think.

 

[MMercury]

Hi Group
3.0Cs with an automatic transmission. This car will start if the shift lever is placed in park or neutral. No need to turn the key to the start position. If the shift lever is in one of the other positions the car can be started by turning the key to the start position. If the car is running and the shift lever is put in park or neutral the starter will try to start the engine.
My guess for a lack of a good one is the starter relay (automatic transmission). Does anyone know were this relay is located?
TomC in Ohio

You may have an issue with a neutral safety start switch or an associated part. This may help: http://www.e9coupe.com/forum/showthread.php?t=5428

 

[Arde]

Starter relay is a good place to start. The only explanation for such odd behavior is that the wiring has been tampered with or some sort of water damage.

The neutral safety switch is obviously working, else you would not see the different behavior between P/N and other selections.

I would remove the starter relay and troubleshoot right at its 4 incoming wires.

 

[MMercury]

Starter relay is a good place to start. The only explanation for such odd behavior is that the wiring has been tampered with or some sort of water damage.

The neutral safety switch is obviously working, else you would not see the different behavior between P/N and other selections.

I would remove the starter relay and troubleshoot right at its 4 incoming wires.

Perhaps I do not, or did not, understand the original post. I was left with the impression that the engine could be started by using the shift lever - without a key. Normally, the only part of the ignition system directly engaged by the shift linkage is the NS Switch. Conversely, if the switch were functioning as intended, would it not prevent starting in other gears, which appears to be a complained of symptom? My first reaction was to wonder whether the switch wiring had been modified, or if the mechanical fork on the switch had been broken, as I once removed such an example along with a roll (or two) of gooey electrical tape and UL-listed wire nuts. If I remember correctly, the switch's function had been defeated, enabling the engine to start in any gear. (Imagine the fun when started in gear on a cold morning when the fast idle kicks in.) Adding to the adventure was an ignition switch buggered as part of an unsuccessful theft attempt. (They got the radio, both AM and FM!) In that instance, someone improvised and had the ignition/starter switch jury rigged from what is often referred to as a "diagnostic port" near the brake fluid reservoir.

I have not considered the switch's circuitry, nor have I handled a switch in many years, and readily concede being wrong on many occasions. My only thought was to examine the wiring and the switch for obvious modifications, along with any other circuitry that is part of the starting and ignition systems. That may even include the so-called diagnostic circuitry, if the subject vehicle is so equipped.

 

[Honolulu]

This may be an intentional re-wire by a previous owner! It was so on my first BMW, a '70 2002a that I bought from a disabled guy. Very much the mechanic with that '02 and his hopped-up Mini Cooper S, also with an auto trans, back in about 1978. The Mini ran a common sump for the engine and trans, using some sort of graphite oil. Another item one doesn't see any more.

He explained that he couldn't work the pedals, so he had the car rigged for full hand control. This included rewiring to start the car when the shifter was in neutral or park, so you had to immediately shift to reverse or drive when the engine lit. The key cylinder was removed and one had to switch the ignition on using a tool of some sort stuck into the gap where the cylinder had been.

I drove the car briefly that way, then got a new switch assembly, removed the column and installed it. I guess I fixed whatever else had been tweaked as well; I was gung ho those days and spent a lot on small parts. The '70 had a sunroof and was pretty nice by the time I totalled it, sandwiched on the freeway. Took a Corvette in the back and something in front. Too bad, but I parted the car for what I had in it, so I came out pretty well.