[henpenben]

hello,
my 2007 E90 328XI (220,000mi) recently was driving rough. I diagnosed a bad ignition coil and replaced it, and the car was fine for a couple of weeks.
I took a short trip to the store, and the car started fine but the revs started going wildly up and down after about 30 seconds. I shut the car off and attempted to restart it, but it simply cranked with no startup. I then tried to bump-start as I was on a hill, and the engine spun but did not start.
Trying to start the car now, it will crank over and over but does not start. The car has been sitting for a few weeks now and appears to have also leaked a decent amount of coolant, which was not a problem I had previously noticed.

Codes present:
P0016
P0340
P0365
P1124
P1417
P1639

also present, but have been ignored for years and unlikely to be the issue:
P0128
P2402


From my research I found the first three codes to be related to the intake cam sensor, or possibly the VANOS solenoid. I removed and inspected the solenoid and it looked fine. I swapped the intake cam sensor with another from a different, working e90. No change on my vehicle, and the other e90 still ran fine with my sensor.

Any suggestions on what to try next? I can easily swap any sensor over from the second e90 for troubleshooting purposes if it can help diagnostics

[henpenben]

just bumping this in hopes somebody can help out.

I've since replaced the crank sensor, although the old one seem to test fine. No change.

I popped the fuel rail and it sprayed fuel, and also tried a bit of starting fluid down the intake ports. no change, I believe I can hear the fuel pump prime, seems to not be a fuelling issue.

I pulled a spark plug and grounded it, but left it connected to the ignition coil. I tried cranking it like this and did not witness any spark.

all fuses in the glove box compartment have been checked and are OK
I've just remembered in the night it broke down, a friend came and attempted to jump start me. He hooked the cables up backwards... This may have had some additional impact. So I might be looking at multiple issues here.

Are there any other fuses on this car?

[k90]

Codes tell also that you don't have functional throttle body atm. for a reason or another. Which could explain the sudden ramping up / down of the RPM.
Bet if the computer doesn't find functional throttle body it won't lit up the engine.

Originally Posted by henpenben

He hooked the cables up backwards... This may have had some additional impact. So I might be looking at multiple issues here.

Ouch.

Originally Posted by henpenben

Are there any other fuses on this car?

Inside E-Box. Where the DME lives.
"How to remove dme e90" should give you results that help you to locate the thing.

[henpenben]

Originally Posted by k90

Codes tell also that you don't have functional throttle body atm. for a reason or another. Which could explain the sudden ramping up / down of the RPM.
Bet if the computer doesn't find functional throttle body it won't lit up the engine.

I do know it will fire with no MAF or TB from testing in the past after replacing the starter. I thought this code would have simply been because my intake manifold was fully removed, but the code came back as pending after reinstallation. It seems a bit odd for so many codes to come up at once, I'd guess it is still something else electrical rather than multiple sensor failure + throttle body failure.

Originally Posted by k90

Inside E-Box. Where the DME lives.
"How to remove dme e90" should give you results that help you to locate the thing.

Thanks, I found the little tiny fusebox, and one of the 30A fuses was blown (second from right). I replaced it and now the engine has spark, it sputtered once. I suspect this was the result of the backwards jump, as it did not blow again after trying to crank the car multiple times.


The same codes are present, although P1197 has also appeared. A cursory search tells me this is the "differential pressure sensor"; I probably forgot or broke it while reinstalling the intake manifold and etc tonight.


Given that I performed earlier sensor swap tests with presumably the same blown fuse, I will again swap two known working cam sensors in and see if it makes any difference, just in case.

[k90]

Is your engine N52 or N53?

Did you clear the codes?

I assume the blown fuse was F02:

• Coolant thermostat
• Electric coolant pump
• Exhaust camshaft sensor
• Exhaust VANOS solenoid
• Intake camshaft sensor
• Intake VANOS solenoid

Did the new fuse survive?

[henpenben]

Originally Posted by k90

Is your engine N52 or N53?

Did you clear the codes?

...

Did the new fuse survive?

N52 (I think it's specifically N52k)

the new fuse survived, I checked it after cranking and it was still good.