HELP! Long list of Code Readouts / Heavy misfire -2001 540i
 

Car is barely running. I thought it was bad gas but i smelled electrical trouble upon hesitation. Heavy hesitation but will idle laboriuosly. Did get a bit wet inside during hurricane-run-out-of-fuel episode, but ran a few weeks after that w/o trouble. Sounds like a diesel up front left of motor.

Here is a list of code readouts: (peake tool r5/fcx)
Table OF
71 - camshaft position sensor cyl#1-4
8C – map controlled thermostat
3E - misfire random / multiple cylinders
39 - misfire cylinder#2
37 - misfire cylinder#3
38 - misfire cylinder#7
5d - evaporative emission system
72 - air mass sensor
E5 - pedal position sensor supply voltage
21 - camshaft vanos control cyl#1-4
22 - camshaft vanos control cyl#5-8
82 - Drive by wire throttle
62 – evap emission system purge valve
A5 – vanos output stage cyl#1-4
A6 – vanos output stage cyl#5-8
34 - misfire cyl#4
36 – misfire cyl#6
35 - misfire cyl#8


Please help in my diagnosis. Does this spell vanos trouble??!!????

Do you mean literally smelled electrical trouble?

When you clear the codes what comes back?

That's a lot of codes. Sounds electrical like a bad ECU etc...

Yup, with the first real bad hesitation I limped the car to the side of the road and it was barely running....no or intermittant response on the throttle. Eventually it came around enough to get rolling - albeit roughly.

I got a quick whiff of electrical failure - I know this well from my MG & Triumph restoration days.

I didnt clear the codes. How do I do that? The Peake manual doesnt really say.

Cleared Codes and Re-tested
 

I cleared the codes and reset the light. I disconnected the Peake tool and went for a ride. Check Engine Light (or MIL) came back on and flashing. I re read the codes and got 7 out of the original 18 codes back:

62 Evap Emission system purge valve
8C MAP controlled thermostat circ/control
A5 vanos output stage cylinder 1-4
A6 vanos output stage cylinder 5-8
3E Misfire random/multiple cylinders
34 Misfire cyl#4
39 Misfire cyl#8

Its less thankfully but does it shed any more light on the problem?

An electrical issue is the only reason I can come up with to get that variety of codes.

I'd pull the ECU and see if it smells burnt.

Thanks very much Jared.
Where can I find the ECU? Is it under the climate control filter on the passenger side? Which one ?

I would be guessing on the 540. It is usually along the firewall, passenger side.

Thanks Jeron
 

I'll take a look tonight. I suspect its above the glove box like an earlier model 5.
I saw a picture on-line of the unit and it looks just like the Motronic units from my 944 cars.
thanks again, i'll let you know how it goes.

DME out & in
 

I took out the DME/CPU and opened it up. No burnt smell or anything 'obviously' bad. Cleared the codes and ran it and rechecked the codes. Much the same as the second set of reads(7 of them).

The burnt smell is very faint in that sealed of area. There are 5 other relays under there: 1 green, 1 blue, 1 red, 1 brown, 1 tan with what looks as fuse links in it.

What do they do or can you direct me to an on line schematic?

ps. car ran a bit different : still missing -but in different rpms tan before - and a much lower idle - around 500rpm.

I dont know of any online E39 schematics. The Bentley repair manual is what you need. They are expensive for E39, $100-150, and come in two large volumes.