2006 Z4 3.0 Won't start, no noise, battery is fine

[stal023]

Well, I jumped in the car to go to work and it started to turn over and then went completely dead (as in absolutely no sounds what so ever). Tested the battery and it is good, connection is good. Trunk light is on and if I turn the key to post 2, all dash lights come on and head lights come on. Only light that doesn't come on is the dome light but that hasn't been coming on for a couple weeks now (could just be a coincidence).

The car was starting really labored but I just thought it was due to the cold and then we got warm weather and the car fired right up every time (for about a week). Drove it the night before. No problems.

I had gotten a new scanner and ran all the systems with the innova 5610 and it showed that the alternator was giving higher voltage. I don't remember exactly what it said and I didn't take a screenshot but I know it was under 15.

I've read the ignition switch goes out on these but I'm seeking advice on where to go next?

[pungo]

1. How did you verify the battery is "fine"?
2. What is the resting battery voltage, and while turning the key to start?
3. Did you use a load tester to verify the battery health?
4. Does it have an auto or manual trans?

[JAS1169]

Locate the starter. With the side of hammer or a larger wrench give the starter 3 or 4 sharp taps. Now try starting the car. If it starts you know it's the starter. (if it doesn't start it still can be the starter)
Starters have electrical contacts inside, if you attempt to start the car and it stops on a worn dead spot you'll get nothing if you then attempt to start the car. When you tap the starter it sometimes moves off the worn spot and the car will start.

I'd redo the scanner. However, it's most likely the starter or ignition switch

[pungo]

Originally Posted by JAS1169

Locate the starter. With the side of hammer or a larger wrench give the starter 3 or 4 sharp taps.

IDK, many of the new replacement starters have a label on them that says "do not strike with hammer", I assume due to fragile internals.
I can't say whether it's safe to apply sharp taps from hammer to the OP starter, but I would test if the solenoid on the starter is receiving power when the key is turned as a 1st step since all the tapping in the world is not going to make the starter turn if power is not making it to the solenoid

I hear you though, people have been tapping on starters since as long as I can remember, but maybe new manufacturing designs causes issues when striked, IDK...

[stal023]

Originally Posted by pungo

IDK, many of the new replacement starters have a label on them that says "do not strike with hammer", I assume due to fragile internals.
I can't say whether it's safe to apply sharp taps from hammer to the OP starter, but I would test if the solenoid on the starter is receiving power when the key is turned as a 1st step since all the tapping in the world is not going to make the starter turn if power is not making it to the solenoid

I hear you though, people have been tapping on starters since as long as I can remember, but maybe new manufacturing designs causes issues when striked, IDK...

Attachment 3666614

How am I testing that?

[stal023]

Originally Posted by pungo

1. How did you verify the battery is "fine"?
2. What is the resting battery voltage, and while turning the key to start?
3. Did you use a load tester to verify the battery health?
4. Does it have an auto or manual trans?

I didn't test it under a load but I will take it into an auto store to get it tested under a load before I completely rule out the battery. I have no way to test the voltage while turning the key since it's just me. I have a manual.

[bob'smerlot]

I bought one of these https://www.amazon.com/TOPDON-BT100-...%2C138&sr=8-10
Really like it. Also double-checked it against the 'big boy' stores and it read the same.

[bob'smerlot]

Or, if you want to know right now, jump it with either another battery or a booster.
My monies' on a bad battery.

[stal023]

It's not the battery. I bypassed it and it still wouldn't start plus I just took it in to get a load test just in case. It has to either be the starter or ignition switch. Which of the two, I am hoping for ignition switch since the starter is a PIA to get to. I am struggling to get to the switch to test it. Why put it under the intake manifold is beyond me.

[pungo]

It's good you ruled out the battery since without a known good healthy battery, you'd be chasing your tail. The clutch and ignition switch as well as EWS/DME come into play before power is sent to the starter solenoid. Checking the output of the EWS will determine if it's sending 12v toward the starter solenoid when the key is turned to start.

[JAS1169]

Originally Posted by stal023

It's not the battery. I bypassed it and it still wouldn't start plus I just took it in to get a load test just in case. It has to either be the starter or ignition switch. Which of the two, I am hoping for ignition switch since the starter is a PIA to get to. I am struggling to get to the switch to test it. Why put it under the intake manifold is beyond me.

1st, hope it's the ignition switch as well. The above posting kind of confused me. Here is a youtube on changing out the ignition switch, which isn't really a hard thing to do. I'm unaware of any test for an ignition switch other than replacing it with a new one and then seeing if the new ignition switch corrects the issue.

[pungo]

Originally Posted by JAS1169

1st, hope it's the ignition switch as well. The above posting kind of confused me. Here is a youtube on changing out the ignition switch, which isn't really a hard thing to do. I'm unaware of any test for an ignition switch other than replacing it with a new one and then seeing if the new ignition switch corrects the issue.

Sure, there's more than one way to diagnose electrical faults. I prefer to reference the schematics to determine where I can perform tests/checks rather than buying parts and swapping them out in hopes that fixes the fault.

It may very well be the ignition switch since that's a common failure, but I've also seen several clutch switches that have gone bad, where a quick coding to disable the clutch check resolved. I've also seen wires in the engine bay that were chewed by rodents cause a no start situation.

Since the OP said "The car was starting really labored" it's kinda pointing to the starter itself or power/ground for the starter

[stal023]

Originally Posted by pungo

Sure, there's more than one way to diagnose electrical faults. I prefer to reference the schematics to determine where I can perform tests/checks rather than buying parts and swapping them out in hopes that fixes the fault.

It may very well be the ignition switch since that's a common failure, but I've also seen several clutch switches that have gone bad, where a quick coding to disable the clutch check resolved. I've also seen wires in the engine bay that were chewed by rodents cause a no start situation.

Since the OP said "The car was starting really labored" it's kinda pointing to the starter itself or power/ground for the starter

I believe it is the starter since I was finally able to pull the ignition cable that connects to the starter (no easy task, had to get 11" needle nose pliers and get my hand in from the side to push the metal tab). I tested it and it is getting almost 12V when I try to start which leads me to believe the starter is toast. So I started the process of taking out the intake manifold. Why you would put the starter under the intake manifold is beyond me. So grateful this happened in my driveway as I would have been calling a tow and had an even bigger headache.

[JAS1169]

Best of luck with it, I believe there are some good video's on youtube on doing this change out.

[stal023]

It was indeed the starter. Finally got it installed last night. Can't say it was a fun job so I hope this starter lasts a long time. Mine was the original so it did last for a good bit of time