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Discussion Starter #1 (Edited)
I DON'T HAVE ANY CODES, SES LIGHT, OR WARNINGS! So far I cannot remember the last time I had a day like that. Sad isn't it? :crying:

Current Codes:
b2 - Catalyst System Efficiency, Cyl #1-3
b3 - Catalyst System Efficiency, Cyl #4-6
03 - Fuel Injector, Cyl #1
Cd - Misfire during warm-up, Cyl #1
d2 - Misfire during warm-up, Cyl #6
d5 - Misfire during warm-up, multiple cylinders

* Yes I have cleared these codes many times and they continue to return
** Only action taken so far is running a fuel injector cleaning additive through my tank

Car runs great! I only notice the misfiring when the car is warmed up and at idle. Other than that no problems. When stopped and idling, I will feel a slight shudder cause by the engine, nothing severe, and I can see the tachometer twitching around a bit.

The d2 and d5 codes are new as of today. Originally I was going to get my injectors cleaned or replaced, assuming the injector for Cyl #1 was bad. But with these new codes I want to ensure there isn't anything else going on.

Thoughts?? Thanks guys.

There's always the chance that any one of these items was installed improperly.
Parts recently replaced
Water Pump, W/P pulley, T-stat, both Temp Sensors, belts, CPS x4, TPS x2, O2 sensors x4, Oil Change, cleaned TBs, Spark Plugs, Fuel Breather Valve, SAS cut-off valve, cleaned SAS tube of carbon buildup, all vacuum lines/hoses/o-rings related to these items and fuel pressure regulator, o-rings and gaskets for the heat exchanger, Dinan MAF housings, oh and the dipstick o-rings for good measure! ;)
http://www.m5board.com/vbulletin/e3...ssues-after-big-service-need-boards-help.html
 

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After all that still codes...something isn't right. Get a compression test done. Hope all the parts you replaced were with OEM parts. Any ECU software?
 

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I feel yr pain. The last 2 times I ran Techron, towards the end of the full tank I got SES lights. Cat codes each time. Turns out I had a bad Cat. Luckily it was replaced under warranty by BMW.
 

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Just read your post - bummer. Are the guys that did the work helping you out or just scratching their heads/guessing? I get an intermittent b2 soft code (no SES), but am assuming it's related to aged pre-cat O2 sensors driving a rich mixture and also my heavy foot. You just did an aftermarket software reflash, right? What do those guys say?
 

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Our remap was way before these error codes appeared.

I still have the suspicion something is wrong with the O2-sensor replacement....

Or the bunges around the sensors are cracked...
 

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Discussion Starter #6 (Edited)
Our remap was way before these error codes appeared.

I still have the suspicion something is wrong with the O2-sensor replacement....

Or the bunges around the sensors are cracked...
I've had the b2 and b3 codes since before the Alpha-N software. I assume my cats are bad and am planning to replace them.

The other codes are the ones I am curious about. Not sure where to go from here. I will have the O2 sensors and bungs closely inspected.

After all that still codes...something isn't right. Get a compression test done. Hope all the parts you replaced were with OEM parts. Any ECU software?
Compression and leak testing was done. Everything passed with flying colors. All OEM parts. ECU see my signature.
 

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Possibly a bad connection of the fuel injector wiring harness box at cyl #1, perhaps.
 

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I've had the b2 and b3 codes since before the Alpha-N software. I assume my cats are bad and am planning to replace them.

The other codes are the ones I am curious about. Not sure where to go from here. I will have the O2 sensors and bungs closely inspected.



Compression and leak testing was done. Everything passed with flying colors. All OEM parts. ECU see my signature.
Makes me nervous bout getting a Peake code reader,but if somethings wrong,its better to know earlier rather than later!
 

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Not sure if this applies in your case, but if you're running cool, the ECU will tend to dump more fuel, and over time it's possible to lead to b2/b3 codes without the cats being bad. Have you cross checked with your fuel adaptation values?
 

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Discussion Starter #10 (Edited)
Not sure if this applies in your case, but if you're running cool, the ECU will tend to dump more fuel, and over time it's possible to lead to b2/b3 codes without the cats being bad. Have you cross checked with your fuel adaptation values?
I had been having t-stat issues and running cool for a few months, could have helped foul up the cats. All adaptation values were reset a few months ago. Could still be worth resetting again.

I'm still quite positive the cat and misfire codes are unrelated. I will replace the cats but I'm more worried about the fuel injector and misfire issues.
 

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I had been having t-stat issues and running cool for a few months, could have helped foul up the cats. All adaptation values were reset a few months ago. Could still be worth resetting again.

I'm still quite positive the cat and misfire codes are unrelated. I will replace the cats but I'm more worried about the fuel injector and misfire issues.
Your not going to want to hear this, but I have to agree with Kumaran. I had a #6 injector issue after the SC was installed. The wire harness APPEARED to be on correct/snug, but wasnt, causing an injector / misfire code.

My suggestions;

1. DONT go out and spend money for new CATS just yet. Now if you are looking for a reason to go aftermarkett (Supersprints) then that is a different story. OEM CATS are going to be SO expensive.

2. Take the plenum off and take a look again at all of your work. Recheck the injector harness and the TPS as long as you are there.

My guess is the injector or possibly the TPS.

Good Luck!
 
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Discussion Starter #12
Thanks Steve.

Next step is going to be getting all injectors cleaned and flow tested, replacing any that require it. I will most likely add Evosport cats when I do my headers and SS x-pipe. Might as well..

Someone mentioned that a service shop can easily do an injector check test. How is this done?
 

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Thanks Steve.

Next step is going to be getting all injectors cleaned and flow tested, replacing any that require it. I will most likely add Evosport cats when I do my headers and SS x-pipe. Might as well..

Someone mentioned that a service shop can easily do an injector check test. How is this done?
"Dont know.....Mongo only pawn in game of life"

Sorry cant help you on that one sir...
 

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Hey Russ,

Get a long flat screwdriver.

Using a good torch, illuminate the under plenum area, and stick the screw driver in there such that you can lever down ever so slightly on the front most part of the fuel injector wiring harness (Bank 1, cyl 1), while the engine is runnning and listen out for any change in engine tone, rumbling, rough running....

You will be able to see the front of this wiring box, and you are lucky its cyl #1, as its right there.

Worth a check and you do not need to remove anything either.

Good Luck
 

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A couple of areas to check

Hi Drew,

Suspect a combination of multiple areas; significant disparity of fuel mixtures between cylinders,
O2 sensor and (though remote) cylinder fault detection accuracy.

As I noted in your earlier thread, #3 is running hotter (lean) while #4, 6 and 8 are running cold (rich).
This points to fuel injector flow rate and/or pattern. The injectors need cleaning and flow-tested. In
addition, fuel pressure should be verified to be at nominal value of 5 bar. Low, or fluctuating fuel
pressures will vary the injectors flow rate, further aggravating a marginal injector.

O2 sensor wiring harness should be carefully examined. The harness, running from right side of the
transmission, splits at the transmission cross-member, with the left side clamped onto the aft side
of the cross-member. Both sides then run behind (on top of) heat-shields and then reappear forward
of the connector boxes. The entire run of harness needs to be carefully checked for damage. Pay
particular attention to the areas behind the heat-shields. Disassemble the connectors for all four
sensors and clean all terminals thoroughly, especially the female ends.

Cracks in the O2 sensor bungs can be difficult to detect, especially when the exhaust pipe is cold.
The area needs to be thoroughly cleaned with a wire brush (or coarse Scotch-Brite pad), along with
brake or carburetor cleaner. Then spray it with a penetrating oil and wipe off excess. Spray again
lightly with brake cleaner and let it evaporate. Any cracks should now be visible with a strong light
and magnifying glass.

Verify proper gap exists between crank sensor and flywheel ring gear teeth. This will help to ensure
correct cylinder position identification for misfire location. Though less likely to be a contributing
factor for the problems at hand, it's still worth checking and is very simple to do.

As with your O2 sensor connectors, clean the harness connectors on all four cam position sensors,
both throttle position sensors, crank position sensor and your MAFS's. To ensure that you have the
best connection possible, apply Stabilant-22 contact enhancer. This stuff is the real-deal and really
works. It's pricey, however a bottle will last forever, especially if diluted with high-purity isopropyl
alcohol.

Good luck Drew,
Alan
 

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Discussion Starter #17
To Update: Car was running fantastic yesterday. Better than I have ever felt her pull. So I thought maybe that fuel additive stuff actually works and I can hold off on the injector cleaning for a little while. The codes didn't return for the first few drives of the day, then at the end of the day I felt the rumble at idle and when I got home, the codes were back.

Now, on to today. I was on my way to work and for the first time I had misfiring while driving, not just at idle. I had a significant loss of power and odd rumbling for about one minute of driving. It appears the problem is getting worse.

Checked codes once at work, new code added to the list: c4 - Misfire, Cyl #1. I think it is very apparent that the injector for cylinder #1 had one too many beers. I have ordered a replacement injector in case the cyl #1 one is found faulty during cleaning and flow testing. I'm going to try to get this done as soon as I can then report back.
 

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Worth a go !

Hey Russ,

Get a long flat screwdriver.

Using a good torch, illuminate the under plenum area, and stick the screw driver in there such that you can lever down ever so slightly on the front most part of the fuel injector wiring harness (Bank 1, cyl 1), while the engine is runnning and listen out for any change in engine tone, rumbling, rough running....

You will be able to see the front of this wiring box, and you are lucky its cyl #1, as its right there.

Worth a check and you do not need to remove anything either.

Good Luck
 
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Discussion Starter #19
Flow test results:
 

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Discussion Starter #20 (Edited)
Bad news, cleaned injectors are in and the misfiring is still there.. Holding for codes. Will update shortly. :(

Worst Birthday Ever

UPDATE: Misfires on cylinder #4 now.

When the injectors were removed, my tech told me that the connectors weren't in perfect condition, as if they had been taken off poorly before. He ensured me that he would put everything back together as snug as possible.

Signs are pointing to bad connection with the injectors from the harness. Hopefully something that can be fixed easily without having to replace the entire engine harness. I have no idea. It is still being diagnosed.

UPDATE 2: torn back down. The clips between the harness and injectors were broken. This was mentioned prior to things being put back together but no mention of possible issues. Luckily they have a spare parts M62 sitting around so just a simple replacement for the 3 broken clips on cyl 3,4, and one other. It looks as if someone yanked them off without taking the little metal latch off first. Sad but oh well..

The tech should finish by 10 or so tonight so hopefully my birthday will improve.. crossing fingers.

On a side note, the oil cooler is all hooked up and my painted plenum and rocker covers look great!
 
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