E36 328i 96 Convertible - running rich

[shanghailoz]

I have a 328i which I've been trying to make happier.

I replaced the O2 sensors a little after I bought it late December 2010, as the old ones were probably shot.

It was having some slight trouble starting in cold mornings, but that cleared up when it got a little warmer, until last week, when it started missing.

Unplugged the MAF to check, and that cleared up it missing.
Took out the MAF, and replaced it today with a new one.
New Spark Plugs have been ordered, and are on their way, but haven't replaced those yet.

Will be hooking up a computer to it shortly to take a look at what the ECU says. Unfortunately although its a 96, its a European import, so OBDI not ODBII, so can't get as much data out of it as I'd like.

Its still running rich, and its missing slightly, but not so much.
Is it a matter of letting the ECU learn the new readings - eg wait a day or two and see how it is, or should I look for the next fault in line?

[shanghailoz]

Got the readings

DME is MS41.0
Production date 14/96

202 - Lambdasonde: Limit
Zylinder 1-3

203 - Lambdasonde: Limit
Zylinder 4-6

8 Luftmassen-Sensor (Heibfilm)
MAF (replaced just now)

12 Drosselklappen - Potentiometer
Throttle flap potentiometer (position sensor)

Makes sense for the first 3, as MAF was hosed.
TPS I'll need to take a look at, maybe do some live readings if Carsoft 6.5 will do it, and look at the long term fuel trim in Live Data.

I also saw EGS errors

153 CAN STATUS - FEHLER
154 CAN Drosselklappen Signal
158 CAN Motor - Drehzahl


I guess I'll change the plugs whenever they deign to arrive, and then clear the MAF related DME errors, and see if they come back.

Other thoughts?

[shanghailoz]

Car is idling like crap at the moment.

Have replaced the MAF
Have replaced the ICV
Have replaced the CCV
Have checked and rechecked vacuum hoses; sprayed carb cleaner around intake manifold and pipes, but zero change to the idle, so don't think its a hose/ vacuum issue.

After replacing the CCV idling seems to change for the better, but still not 100%

Currently its doing the dreaded E36 idle problems... ack.

Haven't replaced the TPS yet (about to order).

If I unplug the TPS idle immediately goes to 4000rpm and stays there - is that normal?
Replug in the TPS, and the idle starts hunting from up / down from 500-2000 odd.
(on todays testing)

Ignoring the TPS - if I drive the car its semi ok for first 10-15 minutes, then the idle drops low, and the car stalls. O2 sensors were replaced, but its possible they installed them backwards - any easy way to check that?

Also on power up, occasionally now up idle shoots to 2000rpm then rolls back down to 1000rpm after a few seconds. Still TPS related?

I've been through most of the intake and replaced by now, but a proper fix is still eluding me.

Any other tips?

[Joylove]

Still sounds like O2 sensors. did you use BOSCH or NGK items?

You can measure the 02 sensors with a multimeter on the heater side (two black wires). Expect 4-15 Ohms.

[shanghailoz]

Used the Siemens (NGK) ones.

How can I check if they're plugged in the correct order?
I have the 96 Euro ODBI 328i, so 2 o2 sensors, not the 4 that the US model has

[shanghailoz]

Replaced the TPS, now idling boings up down on start to 2000-1500-2000-1500 repeatedly, then drops to 1000 odd, but car sounds like crap chugging now.
...and Engine light now on.

Progress of sorts - worse, but has changed since i replaced the TPS (throttle position sensor).

Now its back to idling extremely badly, and almost undriveable.
Will plug in computer and read out once the lapper is charged up.

So far:
Most of the intake has been replaced -

Replaced o2 sensors, fuses, MAF, ICV, PCV, hoses, intake air filter.
Might order some o2 sensors again and see, but its a bit of an expensive test.

Any other ideas?

As I still kind of suspect that the o2 sensors are backwards, can anybody enlighten me in a clear way what order they go?

Just to pre-clarify
I have a EURO ODB1 (Not ODB2) E36 1996 Model, so 2 sensors not 4.

Snarfing the pic from Doug's domain -



The front and back at the engine side go to where on the exhaust side?

Eg Front Bank 1 -> Front sensor, Bank 2 -> Rear Sensor? as per the image, or as i've read on threads here, the other way.

I haven't found a clear answer, and I haven't googled a definitive answer.
Can I be enlightened

[Joylove]

Your 328 is OBD2, however you must use the round socket.

Do you have a laptop with a factory fitted serial port:

Yes: ADS Interface (optimum)
http://www.ebay.co.uk/itm/BMW-INPA-E...-/260872805372

No: VAGCOM + 16-20 pin (partial support including EGS and DME)

Next:

Follow these INPA install instructions.

http://www.bimmerforums.co.uk/forum/...nwards-t74608/

[shanghailoz]

As no-one would actually answer the question, I took the car to the garage and had them swap the o2 sensors around then checked if it did the idling up / down as it was doing previously.

They really wanted to argue with me, but I told them to humor me, and...
Lo, and behold - a car that idles correctly, and I could drive home without problems.

@Joylove - no, its obd1.

I have a working cable and can read the issues quite easily, as I have done above many times.

The issue eventually was what I suspected - the dumb asses at the garage put the o2 sensors the wrong way around.

Sigh.

If you want a job done right, supervise their asses.

So, as far as I can tell, car is ok now +- (although one of the o2 sensors appears to be slightly off according to the computer, so will replace and see)

Lawrence.