2000 E39 540i running terrible...

carjoe · 01-04-2011, 06:54 PM

The car had been running great up until yesterday. Lots of power up top but rough idle, surging, misfires when stopped...

I pulled the codes with a generic OBD2 reader and got these:
P1071
P1074
P1340
P1342
P1159
P1161

I'm a little confused. Some codes are lean, others are fuel trim and the obvious misfire codes.

I've been reading a little about the codes and many point to a faulty MAF. I've got a spare MAF but the one that's in the vehicle now is only 18 months old. Seems a little premature to me. The air filter is good...

I'll pull the plugs and check them tonight as well as swap out the MAF. Has anyone dealt with something like this? Could it be an O2 sensor or a cat? That would probably trigger a code though...I was also thinking it might be a Cam Position Sensor or Crank position sensor but the car never actually dies at idle. It jumps up and down but never dies.

I'll post up later with some findings but would appreciate any input!

J

parm · 01-04-2011, 07:06 PM

Disconnect the maf and see if anything changes with the idle.

carjoe · 01-04-2011, 07:35 PM

The idle definitely changed with the MAF disconnected. Almost stalled, never did though and very "bouncy" while unplugged.

I'm starting to think coil or plugs but the plugs were changed last August at the same time as the VCG and upper timing cover gaskets.

*sigh*

parm · 01-04-2011, 09:14 PM

DO the same with the coils untill you figure out which one or ones are dead you maf seem to be working,

carjoe · 01-04-2011, 11:10 PM

Isn't that similar to changing the plugs while the motor is running?

Here's something interesting, I cleared the codes, swapped coil 1 with coil 2. Car is still idling like hell, I'd even say worst than before but the kicker is that the CEL hasn't thrown a code yet.

Plugs look good...

bmwm5lover · 01-04-2011, 11:45 PM

Mafs can fail quickly. We put a brand new OEM one ona volvo, failed 2 months after, put a new one on and the car was back to normal.

TheMadChigga · 01-05-2011, 09:48 AM

does the CEL flashes?

I had cyl 6 coil pack went out on me, I was able to figure out which coil pack simply by disconnecting the coil pack while the car is idiling, if the idle changes then you know that coil pack is fine, but whichever one you disconnect doesn't change the idle, you probably got a broken one, and make sure you clean the plugs after changing the coil pack, because the unburn fuel can caused the plug to misfire after.

parm · 01-05-2011, 10:37 AM

Quote:

Originally Posted by carjoe

Isn't that similar to changing the plugs while the motor is running?

Here's something interesting, I cleared the codes, swapped coil 1 with coil 2. Car is still idling like hell, I'd even say worst than before but the kicker is that the CEL hasn't thrown a code yet.

Plugs look good...

If you want to get shocked like hell

carjoe · 01-05-2011, 04:44 PM

Chigga, 6 coil packs? Whoa.

I found some Bosch coils for $50 US. Ordered 2 since I know one is bad. Well, I think one is bad...the second one is a just in case since the price was so good.

The car was at least driveable yesterday, not so much today.

I should go check the the web for a coil test. I remember seeing them for E36's and I'm pretty sure these are the same coils that are used on M50/M52's.

MLue1 · 01-05-2011, 06:22 PM

If one of the coils is bad the plugs will show you which one.

I could be as simple as one of the spark plug boots or air leak in the corogated hose between the MAF and the throtle body.

carjoe · 01-05-2011, 06:31 PM

Good call. I'll spray some brake cleaner around the intake manifold and intake boot form the air filter.

Oh, the CEL was flashing this morning when I tested it to see if it was fit for the morning commute. It was not...

TheMadChigga · 01-07-2011, 09:45 AM

Quote:

Originally Posted by carjoe

Good call. I'll spray some brake cleaner around the intake manifold and intake boot form the air filter.

Oh, the CEL was flashing this morning when I tested it to see if it was fit for the morning commute. It was not...

Sounds like coil pack, don't you just love E39s?

carjoe · 01-07-2011, 07:32 PM

Not so much anymore....I've got 2 coils coming. We'll see. I can take repairs but I can't take repairs that make the car undriveable. I thought I knew what to expect but so far, this car has been nothing but a mistake.

Come Spring, or sooner, it's gone.
Love it when everything is working. By far the most amazing car I've ever owned. Goes to the track, hauls the family, commutes awesomely but dammit, I need this thing to be DD reliable.

TheMadChigga · 01-07-2011, 09:27 PM

Quote:

Originally Posted by carjoe

Not so much anymore....I've got 2 coils coming. We'll see. I can take repairs but I can't take repairs that make the car undriveable. I thought I knew what to expect but so far, this car has been nothing but a mistake.

Come Spring, or sooner, it's gone.
Love it when everything is working. By far the most amazing car I've ever owned. Goes to the track, hauls the family, commutes awesomely but dammit, I need this thing to be DD reliable.

They aren't too bad, just gotta have some parts on hands, I picked up quite a bit from parting out, what else is wrong with it?

carjoe · 01-07-2011, 10:27 PM

Rear ball joint, I think.
Needs struts/shocks.
Rear brakes.
Best part-Still leaking oil. I have no idea from where anymore. I did both VCG's, VANOS solenoid gaskets and upper timing covers.

Like I said, love it but can't afford the downtime.
We'll see waht happens after the coil gets swapped.

I was hopign the parts would be here for the weekend but alas, looks like Monday. That's the price you pay for not wanting to pay through the ass. NAPA wanted $240 per coil. I didn't even bother checking the dealer and Rockauto was $48 for Bosch with the boot. I wanted to see what Jared had but he's always over a week for delivery...