New plugs and coils new problems

[kungfukoala]

Hello all. We just bought some new wires and plugs from BavAuto and installed them. Easy job, no issues and now when I turn the key I get no crank.

Lights are good, power is fine but the starter is not even trying to crank. I did disconnect the battery completely during the replacement, but other than that nothing else was touched. Any thoughts? Could a loose plug wire cause the system to not send power to the starter, or some antitheft thing? Really at a loss here. I did not try to reset any of the wires since I ran out of daylight.

1996 Z3. Thanks all.

 

[jonco]

I would start with a basic and check battery charge condition and terminal connections - the lights can operate ok even when there is not enough `juice' to crank. If it is low charge your central locking will be very sluggish. You could try a jump start from a donor car if you have the leads.
Also check your immobiliser fuses (31 and 45 on UK versions) are intact.

 

[EnthuZiaZT]

It sounds like an immobiliser fault to me, at least that is where I would start to look. Firstly though I would check the battery, if you have access to a battery test meter, or can run it to a garage so that they can test it. Make sure that the terminal are on the right way, not being funny but it could happen. Did you switch everything off in the car before you disconnected the battery? It's always advisable to turn everything off, Heater, aircon, lights,radio, etc. That way way there is no power surge through the car management computer when you reconnect. Sorry I'm not more helpful but it's difficult to diagnose a problem with a car remotely.

Mike

 

[jonco]

Start system circuit wiring is shown on Section 1240 on here http://wedophones.com/Manuals/BMW/1998 BMW Z3 - M Roadster Electrical Troubleshooting Manual.pdf

 

[kungfukoala]

Understood, thanks for the suggestions. I took a look again today during daylight hours and double and triple checked the coils, battery terminals aND anti-theft fuses. They all appear to be fine.

I will go Google immobilizer fault because I have no idea what that is. Thanks.

 

[Redline]

A quick check - when you try starting the engine, do the lights dim or go out? Try the interior light rather than LEDs on the dash - they only need a few volts to work.
If they do dim, its likely to be a battery fault or fault with the starter - starting draws a big current that causes the battery voltage to drop. If the battery is faulty it will drop to virtually 0V. If they don't dim then its likely to be immobiliser simply not asking for the engine to crank or some other fault elsewhere.

 

[kungfukoala]

No dimming lights...good thought, thanks

 

[Redline]

No dimming lights...good thought, thanks

Do you have a second key?
If so, have you tried that key?
Have seen posts suggesting that key programming might cause this.

 

[kungfukoala]

Unfortunately no extra key but I think you are on the right track. I feel very strongly that the problem is either something to do with the key or the EWS (anti theft system?). Something preventing current to the starter. I will have to dig deep and see what I can come up with. Thanks all for the help. I will leg you know if I find anything useful.