[coolwhip87]

Howdy all,

I have a manual 2008 328xi with build date (I believe, will check again and update if necessary) of 11/2007. I have a k+dcan cable and access to INPA + the rest of the standard software people on here use along with a multimeter.

Here's my story:
One hot ~88°F day a month and a half ago I drove my car 5 miles, parked for about 10 minutes, then when I got back into my car it would no longer start. When I pressed the button I could hear the starter click once and then a few seconds later click again.

I replaced the starter and my car now is cranking, but still not starting. On the first try of cranking the car after having it sit, it will cough for a moment as if it's going to start, then just the sound of the starter cranking for ~10 seconds before stopping. Subsequent tries result in just the starter cranking with no cough.

I went through some troubleshooting so far of:
- Engine to frame ground strap (the one under drivers side engine mount). Was super corroded and now brand new.
- New battery
- New starter
- Tested fuel pressure at the rail, it is holding pressure properly and fuel pump is priming
- Tried starting both with and without the IBS battery cable plugged in
- Tried starting both with and without the MAF sensor plugged in
- Tried starting with and without a jumpstart from a running donor car
- Tried starting with the second key to my car


Here are the DME codes I am getting from INPA


Here are the CAS codes I am getting from INPA, from what I can interpret they're just saying "Hey the car isn't starting"



Following advice from this thread ( https://www.e90post.com/forums/showthread.php?t=1737532 ) I also have the diagnostics of what voltages are coming through during different operations. Here they are:

Voltage to Terminal 87 was sitting around 12V, didn't grab a screenshot of that. The relay happily clicked between on and off as well.

Voltages without key in ignition:


Voltages With key in, ignition on, not cranking:


Voltages with car cranking:


Then I also have some for when I tried jumping my car

Voltages with car being jumped, ignition on, not cranking:


Voltages with car being jumped, car cranking:



If anyone has any insight on what else I should check, or if there is something I am missing in what I'm looking at, please lay it on me.

In the removal of half the engine bay to replace the starter, is there anything that if forgotten to be plugged in would stop the car from turning over? I saw some mention of the crank position sensor in other threads, and am considering the possibility.

Thanks y'all!

[E30M CW]

I recently had a problem where the car would crank quickly, but would not start.

It ended up being moisture getting into the ECU connector sometimes causing a short and making the water pump run after the engine was shut off and draining the battery, or corrosion on the ECU pins so it couldn't read the throttle pedal or other sensors correctly.

[gbalthrop]

Originally Posted by coolwhip87

... 2008 328xi [MT]... I have a k+dcan cable and access to INPA + the rest of the standard software people on here use along with a multimeter... I replaced the starter and my car now is cranking, but still not starting... Here are the DME codes I am getting from INPA:
[2 DME Codes (8/21/2022): 2A3F & 2A77, BOTH related to VVT; NEITHER should prevent firing when cranked; NO CAS Faults; CAS Fault Codes are shown on 9/3/2022 INPA ScreenPrint; WHAT ABOUT NOW???]...

Your CAS Terminal Status Live Data shows as it SHOULD. If the Starter Cranks when START is pressed with foot on Clutch, CAS is operating normally. Your Crank, NO Fire issue is due to lack of properly-timed spark or injector pulse with pressurized fuel rail.

Your FIRST INPA ScreenPrint shows INPA > Functional Jobs > F4 Error Memory, ALL Modules. It was taken 8/21/2022. Your 2nd INPA ScreenPrint shows INPA > CAS > F4 Error Memory > F1 Read Error Memory. THAT ScreenPrint was made 9/3/2022. If Starter is Cranking, it is likely that NEITHER of those two codes (A10A & A0B4) are "Currently Present" (Fehler Momentan Vorhanden).

Please do CURRENT screenprints of:

1) INPA > Functional Jobs > F4 > Error Memory, ALL Modules, and post it here.

2) If there are any DME Faults, please save & POST ScreenPrints of:
"INPA > DME (Engine | MSV80) > F4 Error Memory > F1 Read Error Memory > F3 Error Memory with FF Data. THAT ScreenPrint should be posted for EACH DME Fault Code.

With THAT information, we can suggest "Next Steps".
George

[coolwhip87]

There is no sign of water damage or corrosion around the DME or any connections so I think that can be ruled out.

Here are the two errors stored in the DME memory:

Code 1:


Code 2:


Then I cleared the functional jobs error memory, attempted to start the car a few times, and got these codes:



Looking them up (specifically code 2A3F Valvetronic Power Supply Undervolt) led me to this thread: https://www.e90post.com/forums/showthread.php?t=1395446

I was most interested in the youtube video linked towards the end. I checked voltage on the cable that provides power to the VVT motor and sure enough it's sitting at only .2V where the main power cable is reading a healthy (but low) 11.2V (I will be getting my battery charged up with a donor car again soon).

This is the engine bay side of the cable, currently reading ~.2V:


Interested in pinpointing where the lack of voltage starts, I followed the cable back and test it at the battery. This time 0V, I then checked at the connector between cable and positive terminal and once again 0V. I believe that this may be the issue.

Here is the port on the positive battery terminal that I was testing. Typically there is a red cable similar to the blue connector IBS cable where my multimeter prod is. The port directly up from the one I am in in the picture reads 11.2V and so does the IBS port. So I assume that the port I am in should also have power. I will be tearing off the cover and checking it out likely tomorrow as it is now pouring rain outside.


It makes sense that the VVT motor not having power would stop my car from starting (I think). Just to be certain, is the port I have my multimeter in supposed to have 12V at all times? I was getting the same reading of 0 both with and without the ignition on.

Thanks

[coolwhip87]

Good news, I got my car to start!!
Bad news, there is a burning smell that comes from the battery compartment. (More on this later)


So today I decided to send it and plug the VVT Power cable into one of the other plugs on the power distribution box that was giving voltage.

Specifically, I did this:


Typically that black connector with red cable is supposed to go in the first slot on the left next to the stud for the (fuse box?) power cable. That first slot was not transmitting any voltage for me so I plugged into the one above.

When looking at the metal plate on its own it seems that there are ratings for each of the metal tines that the plugs attach to. The correct spot and the spot that I used are both marked for "100", the ring that connects with the stud is marked "250", the tine between the original one and the one I used is marked "80" and the tine for the IBS connector is marked "IBS".

Here are front and back shots of what I'm talking about:

From the top side


From the bottom of the plate (Note the numbers marked on the tines)


I will likely try and break apart the "dead" tine and see if there is a fuse or something in the black box that is broken thus causing a lack of power.

I assume the burning smell (unlike any burning I've smelled before, but I also don't have much experience with electronics or plastics) is from the (potential) fuse in between the tine I used and the metal plate burning up slowly. Everything else is plugged in/mounted where it is supposed to be after all.

Once doing that (and with a jump to charge the battery up again), the car had a much faster crank sound and kept coughing like it was going to start. Around the 4th try and ~20 minutes of charging she started no problems. Ran for about 30 seconds while I tried to pinpoint the scent, then I shut her down.

Tried to start one more time without any jump and she started up faster and nicer than I've ever seen before (I did replace the starter and grounds after all). Idled perfect as well.

Final thoughts/questions:

1. What is supposed to be plugged into the tines I used? From looking at the case the plugs enter, the two middle tines (marked 80 and 100) are for one big connector.

2. What would cause the fuse between the box and the tine to blow?

Thanks

[gbalthrop]

Originally Posted by coolwhip87

... 1. What is supposed to be plugged into the tines I used? From looking at the case the plugs enter,
the two middle tines (marked 80 and 100) are for one big connector.
2. What would cause the fuse between the box and the tine to blow?

See the attached photo with LABELS of each of the wires attached to the Rear Power Distribution Panel on top of my 3/2007 build 328xi.
You have correctly identified the VVT Power supply "Fusible Link" and Small Red B+ Cable running down to the INBOARD "Transfer Point",
from which a similar cable goes forward to the VVT connector on side of E-Box.

If there is NO continuity (Infinite resistance) between the side of the fusible link that connects to (+) Battery Terminal and the fused spade
the VVT Cable connects to, then you had a short to ground that "Blew" that fusible link. A repeat performance on the link NOW connected
to the VVT B+ cable is likely without repair of the underlying problem.

Most likely CAUSE of short to ground in VVT B+ Cable: WATER in the battery well, shorting/rusting the Transfer Point (Inboard one of two).
I also attach a photo of the cover of that transfer point. The Outboard Transfer Point with the LARGE Red B+ Cable is the supply for
Starter, and Alternator Connection.

So I would suggest removing the battery and inspecting for water, opening the Transfer Point Covers, and inspecting those Transfer Points.
I would be interested in knowing comparison between:
a) Voltage measured at B+ Battery Post (in relation to Chassis Ground), and
b) Voltage measured at VVT Terminal on side of E-box, also in relation to Chassis Gnd.

Does the odor occur any time the Battery Terminals and VVT Cable are connected, or ONLY with engine running? Is it a sulfur smell
(battery acid boiling), or a "subway electrical smell" related to electrical arcing or short? I would suggest keeping (-) Battery terminal
DIS-connected until inspection and testing is completed.
George

[N54.Kyy]

Ive had a problem recently crank with no start, i replaced the battery, still didnt crank, a friend of mine said check the fuel lines, something might’ve popped off, and i check and boom a line on a fuel pump was popped off, plugged it back in and the car started, if u are checking the fuel lines make sure to check all of them. I was even stranded in the highway when the car literally just turned off out of no where when i was just cruising in the left lane, tried many ways to start the car but didnt work. go towed home and figured out the problem days later,