'95 M3; CEL remains

[Balthazarr]

Failed smog; HC high. I think idling, but have to check. It passed in one speed.
I was so disappointed I didn't even bother to look at the results after leaving the shop.

Replaced O2 sensor 14 months ago hoping it would clear, but hasn't.


Plugs about same time, IIRC. I think they were NGK BKR6KE or 6QUP. I'll look bc I always save the old plugs in the new boxes and date and number them jic.
Checked for cracked hose to HFM. Found small ones at upper connections and taped up past Sunday.
Guess it would behoove me to replace those asap.
Peake code 29: Air Mass Sensor

In the past, I've found that the reader isn't always completely accurate, but it's a starting point.

I checked filter and it didn't look damaged or dirty; shook/tapped out.
Removed HFM and didn't see any buildup on sensor. Guess I should clean anyway when I have the time.
Maybe I should do the pedal stomp test for corroboration.

I forget how to remove those fasteners that hold it to the housing it's been so long., but it obviously requires a special tool; or a pair of pliers that'll grab them.
I haven't touched the ICV in years. Idles just fine.

Printout is in the car. Time for bed. I'll post numbers tomorrow.

[Breeze1]

Failed smog; HC high. I think idling, but have to check. It passed in one speed.
I was so disappointed I didn't even bother to look at the results after leaving the shop.

Replaced O2 sensor 14 months ago hoping it would clear, but hasn't.


Plugs about same time, IIRC. I think they were NGK BKR6KE or 6QUP. I'll look bc I always save the old plugs in the new boxes and date and number them jic.
Checked for cracked hose to HFM. Found small ones at upper connections and taped up past Sunday.
Guess it would behoove me to replace those asap.
Peake code 29: Air Mass Sensor

In the past, I've found that the reader isn't always completely accurate, but it's a starting point.

I checked filter and it didn't look damaged or dirty; shook/tapped out.
Removed HFM and didn't see any buildup on sensor. Guess I should clean anyway when I have the time.
Maybe I should do the pedal stomp test for corroboration.

I forget how to remove those fasteners that hold it to the housing it's been so long., but it obviously requires a special tool; or a pair of pliers that'll grab them.
I haven't touched the ICV in years. Idles just fine.

Printout is in the car. Time for bed. I'll post numbers tomorrow.

"HC high" indicates a rich condition, probably resulting from either excess fuel being dumped to compensate for a vacuum leak (perceived "lean condition"), or a dirty/faulty MAF sensor. IMO your issue lies somewhere in what's in bold in your text. If the cats are overheating they could trigger that as well, but I would look into vacuum leaks/MAF sensor first.

[MarcoZandrini]

Get the OBDFusion app for your smartphone or tablet. Then head over to E46Fanatics and search for threads on OBDFusion in which jfoj has commented. He’s the guru. The app will let you check the MAF measuring air flow and a plethora of other sensors.

[dworthy]

Get the OBDFusion app for your smartphone or tablet. Then head over to E46Fanatics and search for threads on OBDFusion in which jfoj has commented. He’s the guru. The app will let you check the MAF measuring air flow and a plethora of other sensors.

Marc,

That works on OBD-II cars, and this car is an OBD-I type as it's a 1995.


O.P.

Yeah, stomp test blinks will give you some idea as where to start. OBD-I isn't very workable, but you can still see live data with INPA to a point. Now it is a tad slow compared to OBD-II, but it can be a start of where to look first.

Also like noted above, make sure your intake track if fully sealed, that would cause a rich condition. Start with the basics of a smoke test and go from there.

[Balthazarr]

Sounds like a good idea, MZ. Thanks

After looking at reviews, seems like this app is good for OBDII, only.

- - - Updated - - -

What's INPA?

[jclausen]

How hot was the engine the car the cat needs to be very hot, drive on the freeway for 30 mins bring it in put it on the smog machine. This step is very important. Idling the engine won't get the cat hot enough.

[dworthy]

INPA is BMW's old diagnostic program. If you have an older laptop or even a newer one, all you need is the program and a cable to be able to talk to the car. INPA will pull all the codes from every module you have on that car, and allow you to clear codes as well.

Here is a cable and the disk: https://www.ebay.com/itm/BMW-INPA-K-...-/301971578827

Or you can look to find one in the U.S.A. as you will need the 20 pin connector. I use a Dell D-830 Laptop with a true R-232 (Serial) connector to do all my work as those tend to be better than using an USB emulator.

[MarcoZandrini]

Ooops! RTFP! Thanks Darin.

[Balthazarr]

download_20190202_194623.jpg

[Balthazarr]

Tech told me these engines fail HC frequently due to "wrong" plugs. I checked and see I took out the 6EK and replaced with Bosch 7FLDCR in April '18 Shouldn't make a difference, but someone said the NGK were a colder plug.

Also, Realoem doesn't show my intake tract with the non-ASC+T setup. I'm thinking I need to look at the M50 diagrams.

[bmwdirtracer]

You only failed by 4 parts per million, at low speed. I'd recommend that you take Ross's advice, and redo the test with the engine and cats fully warm

[marcva]

Failed smog; HC high. I think idling, but have to check. It passed in one speed.
I was so disappointed I didn't even bother to look at the results after leaving the shop.



Checked for cracked hose to HFM. Found small ones at upper connections and taped up past Sunday.
Guess it would behoove me to replace those asap.
Peake code 29: Air Mass Sensor

Also give the hose downstream from the HFM some squeezes. that tends to rot and fail in the creases where you can't see it until you squeeze. If you have cracks in your hoses, I'd go ahead and replace them both. That's a pretty common source of air leaks, and you've told us your interior rubber is cracking.

[Balthazarr]

I ordered a new air filter and boot. The ICV hoses I can't find in Realoem.
I'm going to try putting in the Part number for the ICV to see which group of diagrams I need to look at.

- - - Updated - - -

Of course I'll need a new IM gasket bc IIRC, getting the hose connected to the ICV requires pulling the manifold.

[dworthy]

I am not sure where you are looking at in the part catalog, but it is there: http://www.realoem.com/bmw/enUS/show...diagId=13_1710

[Balthazarr]

Yeah, I found and ordered them.
I couldn't find my HFM in those diagrams. I remember there was a diagram in that ETK cd I had.

[Balthazarr]

CE is out. Shoulda bought a new HFM in the beginning instead of dickin' around so long.
Now to smog.

[Balthazarr]

Failed again.
HC is higher than before and running 50% methanol for the test. In fact, 89 ppm with less meth previously and now, 144ppm. New cats ordered.
Changing the oil, as well.

[Balthazarr]

Passed.

[dworthy]

So in the end it was a bad cat? Is next year going to be easier as the car will be 25 years by then?