Turn on ignition and car does not crank over, have bumped started it car ran fine battery ok, turned of and would not crank again no the problem lies between ignition switch and starter motor could it be the relay and where is it located... vauahall astra 1994 1.6

I found this

Ok, do the following procedure if it does not work try it again with a new key if problem still exists the ignition switch/passlock sensor needs to be replaced then the following procedure will need to be performed again.

1. Turn key into on position with engine off.
2. Bump key into start position for a second without trying to start it and leave key in on position.
3. Leave key in on position for at least 10 minutes and security light will turn off.
4. Turn key off and wait 5 seconds.
5. Repeat steps 1-4 2 more times for a total of 3 times/30 minutes
6. Vehicle should now start.

I'm going to first assume that you've checked the battery terminals for gunk build-up. If the electrical system is OK, then the problem likely lies in the gas delivery. You might want to check out the starter anyway. Also, replace the fuel filter and put some Sea Foam or equivalent carb/electric ignition jet cleaner in the gas tank. I might add that your car is 17 years old. Start looking. . .

If it is a 3.8 engine change the crank sensor,they go bad on the 3.8 engines.

did you check your battery charge, try a new one, check crank relay, check your starter, if cranking check your ignition system, check fuel , and maybe your immobilizer, go to proffesional tech

i know of no oil that would cause this. anti freeze mixed with oil will. i suggest that you change oil and filter before you run it again

u should try to follow the positive cable back to ecu and make sure u did not loosen the wire accidently by pulling
wiggle them around and see if they are loose this should be were the prob. lies...

Immobilizer armed its self

pull out negative terminal battery located under rear right seat.wait for 5 min n then install again the lead negative terminal.insert the key to ignition cylinder.turn the key on off three times.now start the engine.make sure u use recommended fuel grade.

have u loked into the starter

Have you checked that you have power to the coil on cranking?You may also want to check wether you have a good strong spark at the spark plug.It could be an ignition module breaking down.If you have no power to the coil you may need to change the ignition relay.Its close to the battery.