Non starting automatic

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Bonymaenjack
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Post Wed Sep 14, 2016 8:00 am

I'm considering buying a320 preface lift with an autobox. It hasn't run for quite a while and the owner stated that it's failure to start is due to a gearbox sensor ( which would make sense I suppose) not having owning an auto before where should I start looking .I've not yet seen the car but I'd like to be prepared before making any type of offer as what to expect
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aimlessrock
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Post Wed Sep 14, 2016 8:44 am

worst case, if it were me I would be looking to budget for a good used auto box, autos are not that popular and likely a trader can sort you out a good used one for sensible money.

As an alternative, and assuming the box has problems look to convert to a manual.- it will likely be worth more when finished.
E30 320i Convertible (1989)
190 Mercedes (1988)

"there is nothing more expensive than a cheap E30"
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Brianmoooore
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Post Wed Sep 14, 2016 10:23 am

There are no gearbox sensors that will prevent any E30 from starting.
What there is, on ancient 320's, are two engine sensors, which are mounted in the bell housing, where they pick up a signal from the auto. equivalent of the flywheel.
The two sensors are identical, so can be plugged in the wrong way around (in which case the engine won't run), and are a fairly common item to fail.
Alternatively, (on the manual version, at least. Not sure if the same can happen on an auto, although it probably does), the magnetic pin mounted on the flywheel can detach itself.
IIRC, with one particular sensor failed, you get the fuel pump running when cranking, but no sparks, and with the other sensor failed you get neither.
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BenHar
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Post Thu Sep 15, 2016 10:25 am

Isn't there a switch in the gear lever on autos to only allow it to start in Park or Neutral?

Maybe the switch or the wiring to it has failed?

Ben
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martauto
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Post Thu Sep 15, 2016 5:58 pm

BenHar wrote:Isn't there a switch in the gear lever on autos to only allow it to start in Park or Neutral?

Maybe the switch or the wiring to it has failed?

Ben
Inhibitor switch.
Been there with a Rover P6.
Worth a good look at.

Mart.
Only the E46 cab left now.
Just got too old.
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Brianmoooore
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Post Thu Sep 15, 2016 7:24 pm

Inhibitor switch prevents the engine from cranking, not from starting.
If an engine can be rotated, it would start regardless of the inhibitor switch. (Some of us can remember starting handles!)
I'm assuming that the OP means the car will crank, but not start.
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Bonymaenjack
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Post Thu Sep 15, 2016 7:28 pm

Thanks for the replies regarding whether it's cranking or just not starting I'm not sure yet I've not seen the car yet but I 'd like to be more confident of what it maybe before I take look
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BenHar
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Post Thu Sep 15, 2016 10:31 pm

Brianmoooore wrote: I'm assuming that the OP means the car will crank, but not start.
Never assume anything!

(You don't normally, Brian!)

Ben
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andysheep
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Post Thu Sep 15, 2016 10:52 pm

My 320 cabbie auto would crank but would start due to crapy fuel pump,so try listening for that hum when at the first turn of the key before cranking :D hope it works out :cool:
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aimlessrock
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Post Fri Sep 16, 2016 9:00 am

The state of the shell is more important that the mechanicals, rust can be a real problem and be far more costly to repair. a replacement engine and box can be soured and fitted for reasonable money.

I assume you have read the buying guide on the wiki, if not see the below link.

http://www.e30zone.net/e30zonewiki/inde ... ing_an_E30
E30 320i Convertible (1989)
190 Mercedes (1988)

"there is nothing more expensive than a cheap E30"