First sign of a problem? e60 M5

[sshenton1975]

So some of you may have read my story

Just purchased a 05 M5, 68k miles with new engine 1000 miles ago from BMW

Car drives beautifully and that is even with me taking it carefully whilst running it in.

First oil change is due next week

In the last 2 weeks of ownership, there have been 2 occasions when cold starting that it starts with a slight misfire and the yellow check engine/reduced power symbol comes on. Switch off and switch on - all is well. No symptoms at all when driving and only happens when cold

Any idea? No stored or recorded codes on OBD reader.....

[AW10]

My guess would be an oxygen sensor. You need to use more specialist software than an OBD reader to find codes for faults that are no longer present. Or have the OBD reader handy so that you can plug it in immediately without shutting the engine down the next time the fault occurs.

[Rahul uk]

I am no mechanical expert but I experienced this on my E60 M5 and it turned out to be an throttle actuator fault. Had it replaced under warranty.

[davewhitt]

check battery first

[jovie]

davewhitt said:

check battery first

+1

[jcolley]

There is nothing in the E60 which will cause a check engine light without storing a code in the DME.

The DME senses the problem, records the error, then sends a CAN signal to the CCC/CIC and instrument cluster to activate the warning lights.

That error code is the key. If you have it read and post here, I can look it up for you.

[FredBasset]

John, bit of a lurker on forums and run an E60M5 for three years. I've seen many of your posts and have the utmost respect for you but have to disagree based on personal experience. I do get the check engine light with no code, bizarrely only a couple of times a year in sub zero temps after the car has stood in the rain. Been like this for a couple of years.

However there is another more serious fault I had which was causing the CEL and a slight rough running, the vanos hose was leaking. All sorted under warranty but something to check.

Regards
Fred

[jcolley]

FredBasset said:

John, bit of a lurker on forums and run an E60M5 for three years. I've seen many of your posts and have the utmost respect for you but have to disagree based on personal experience. I do get the check engine light with no code, bizarrely only a couple of times a year in sub zero temps after the car has stood in the rain. Been like this for a couple of years.

However there is another more serious fault I had which was causing the CEL and a slight rough running, the vanos hose was leaking. All sorted under warranty but something to check.

Regards
Fred

Fred,

Which diagnostic software was used to read out the codes? Something I discovered recently using INPA was that apparently the DME has an "error memory" (EM) and a "history memory" (HM), both of which can be read out and/or cleared using INPA. However, using ISTA/D, I'm unable to see any of the codes stored in HM which are readily visible using INPA. I believe that HM is what some refer to as "shadow codes" that may or may not show up at times. And by no means am I insinuating that anyone is being less than forthright with their reports, but I have had a dealer technician tell me my car had no codes stored when I took it in under warranty when I had read them myself not 30 minutes prior. Their expression changes a bit when you say "Really? Not even a 4FA0 or 27B9?" Again, no implication there of anything, but that behavior is exactly what lead me to get my own software and learn more about the car. Hopefully you chaps across the pond there have more honest techs than we do.

Just out of curiosity, you mention cold temps and the VANOS line. After replacing the leaking VANOS hose (was this the internal hard pipe on the discharge of the pump?), do you still get the CEL?

Cheers,
Jim

[FredBasset]

Hi John, it was the local BMW dealer's software.

I've had the problem of the CEL since I bought the car three years ago, cold weather, left in the rain. Usually clears after a day or two. This winter I only got it a couple of times as we have had few frosts in the UK.

March time the light came on and I thought it could be the same thing, I had time to drop it to the dealer again and they diagnosed the internal pipe (which has also previously been replaced). I have wondered if the low temps caused the oil pressure to be low in previous years giving early warning of the VANOS issue. But we won't know until next winter, assuming that we get sub zero temperatures.

Somewhat annoyingly my car threw a DSC/Engine fault problem a couple of days back, the idle speed control valve on one bank was replaced a couple of months ago, I suspect this is the other bank giving out. Pleased I have that warranty from BMW/Mondial.

Regards
Fred

[jcolley]

FredBasset said:

Hi John, it was the local BMW dealer's software.

I've had the problem of the CEL since I bought the car three years ago, cold weather, left in the rain. Usually clears after a day or two. This winter I only got it a couple of times as we have had few frosts in the UK.

March time the light came on and I thought it could be the same thing, I had time to drop it to the dealer again and they diagnosed the internal pipe (which has also previously been replaced). I have wondered if the low temps caused the oil pressure to be low in previous years giving early warning of the VANOS issue. But we won't know until next winter, assuming that we get sub zero temperatures.

Somewhat annoyingly my car threw a DSC/Engine fault problem a couple of days back, the idle speed control valve on one bank was replaced a couple of months ago, I suspect this is the other bank giving out. Pleased I have that warranty from BMW/Mondial.

Regards
Fred

Derailing OP's thread a bit here, but when I first purchased my 2006 with 50k miles about 2 years ago, I had similar problems on the few nights I left the car out of the garage through the winter. On startup, I would receive a CEL and when scanned, a VANOS low pressure code would turn up. However, when performing the VANOS pressure test using either a manual pressure gage or the test routine at the dealership (ISTA/D with the IMIB test box), the pressure would read normal.

The VANOS on the S85 has an accumulator similar to that of the S62. On early production S62s, there was no solenoid valve to hold pressure in when the engine wasn't running, but it was added on later years and I believe could be performed as a recall if a client asked for it. This holds pressure in by shutting when the engine is off and the DME energizes (opens) it as the engine turns over for starting. The accumulator then pressurizes the system and holds pressure until the VANOS pump discharge builds up and maintains pressure.

I always suspected that perhaps in really cold temps, the accumulator valve would leak by a bit and allow pressure to slowly drop. This would trip the code on startup, but then pressure would be fine after running. I never had confirmation for this and never saw it again after switching to 0W-40 oil since I suspect the VANOS pump can ramp up the pressure faster on start.