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Peake codes 90 and 91 are equivalent to P0172 and P0175. I think AE and AF bring in these 2 P-codes but I'm not 100% sure.

All 4 of these codes are to do with the AFR going so rich or so lean on both banks, the DME can't correct for it. Seems like 90% of the time, this is caused by bad MAF's, either due to age or counterfeit/wrong model MAF's being installed. How old are yours?

The 80 code for the idle deviation is probably due to the above as well.

How is the car running? Rough idle, poor gas mileage, down on power?

Malcolm
 

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Peake codes 90 and 91 are equivalent to P0172 and P0175. I think AE and AF bring in these 2 P-codes but I'm not 100% sure.

All 4 of these codes are to do with the AFR going so rich or so lean on both banks, the DME can't correct for it. Seems like 90% of the time, this is caused by bad MAF's, either due to age or counterfeit/wrong model MAF's being installed. How old are yours?

The 80 code for the idle deviation is probably due to the above as well.

How is the car running? Rough idle, poor gas mileage, down on power?

Malcolm
The 90/1 & AE/F codes just came back a couple days ago. I'm surprised 80 didn't come back because the car idles < 500rpm.

The car seems to be running well & not necessarily low on power (but it's been mine just 2 years). My mileage is 17mpg in mixed driving. My MAFs are probably the originals so they have 110K miles on them. I did the MAF test a few months ago, and I think I got 125-130lph on it.

I replaced both front O2 sensors last month and replaced 2 or 3 vacuum hoses with holes in them.
 

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Some recent threads have shown that passing the secret menu MAF test does not guarantee the MAFs are good. I suggest you replace the MAF's. The price of genuine BMW ones has come down significantly lately.

Malcolm
 

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I would agree, but he could just try unplugging the mafs for a 100 miles to see. Although I am getting less convinced of how this turns out from recent threads. Now I am beginning to believe that when you unplug the MAFs if there is any change in the car the MAFs are shot. Even if the change is the car runs worse.
 

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1b c4 c9

Beat the snot out of my car last night,
High Gear Hard Pulls at High RPM's put me in a Limp Mode....

1B-C4-C9

Can anyone shoot me in the right direction

01 M5 w/ 37,000 Miles
Looked up repairs from previous owner and had full tune up about 3 years ago
8 Plugs and Coil Packs!
Runs great at normal driving...

Thanks for your help!
 

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Beat the snot out of my car last night,
High Gear Hard Pulls at High RPM's put me in a Limp Mode....

1B-C4-C9

Can anyone shoot me in the right direction

01 M5 w/ 37,000 Miles
Looked up repairs from previous owner and had full tune up about 3 years ago
8 Plugs and Coil Packs!
Runs great at normal driving...

Thanks for your help!
You typed 1B which means use lookup table 18 in the book that came with the reader. C4 and 9 are misfire codes for cylinder 1 and 6. Did you clear the codes? At what rpm does it go into limp mode and do you see a warning on the dash? I am wondering if it is real limp mode or if you are just feeling what happens when cylinders are shut down?

If you repeat these same codes (so clear them each time) at high rpm it suggests coils or possibly an electrical supply problem. A coil demands a huge amount of power at high rpm and requires recovery time. Recovery time can be negatively affected by damaged spark plug boots or internal damage.
 

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Misfire Code Help

02 E39 M5...Getting Codes CD, CF,D0, D5, regularly and OD and 57 recently, along with 90 yesterday. Back on 6/24 got a 01 - Fuel Pump relay code which was just after the fuel pump was changed, but not since.
Occasionally running rough at startup. Appears to be a right bank only problem, possible intake leak. Swapped MAF's side to side and still have right bank misfire codes. SES came on yesterday last time was 6/24 with limp mode prior to fuel pump install. Just rough at warm-up, clears when warmed.
At highway speeds applying medium throttle from coast, sometimes get a bump or shutter, feels like a differential mount rock, but don't think so as only happens at highway speeds. Not sure if this is related.

Thoughts? Thanks
 

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The 1 was likely from the change in the pump. If you cycled the key or something with the pump unplugged. That code checks the path thru the contacts which goes thru the pump to ground.

All the other codes together point to either an dirty or poorly functioning injector or a air leak. The only air leaks that happen to one bank alone are either the o rings for the injectors or the rings on the tubes that connect the throttle bodies. That said there is the nasty little elbow where the Evap system joins the ICV system and although it should effect both banks 80% of the time only effects bank 1, 10% for bank 2 and 10% both banks. You can check that elbow on your way to the injectors.
Injectors sometimes work better when warm, o rings can seal as the metal expands. The throttle on issue with the highway makes me think it might be a sticky injector.

The simple thing would be to start with a couple of bottles of really good fuel system/injector cleaner and see if there is an improvement over the next tank or two. If you have a problem doubling the strength is a good idea. You could add with that a injector lube like Lucas upper cylinder lube. You are in the States so you can get Techtron or CRC "guarantied to pass" and Lucas then continue with the Lucas until the bottle is empty. The Lucas comes in liter bottles that do a few tanks.

If you get improvement or even a cure you still need to pull the injectors for cleaning but use the Lucas until that time. If you get little improvement then pull them send them for cleaning and replace the o rings at the same time. Not a guaranty because it could still be a leak at the tube to the throttles or I suppose under a throttle(never heard of that), but that is such a bear of a job you want to do everything else first.
 

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I would say the 0D code means you have a bad pre-cat O2 sensor on Bank 1. This could explain all the bank 1 codes you are having. How old are the O2 sensors?

If you don't want to spring for new pre-cats (they're pretty cheap and easy to install), you can swap them from bank to bank and see if the codes move to the other side.

By the way, the MAF's aren't bank-specific so swapping them won't cause a problem to swich to the other bank.

Malcolm
 

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Not sure I agree. He has codes for both sensors on that bank plus fuel codes.Let alone the misfires. You maybe stretching things. But then again what do I know you have the same experience. The object is to give the right answer not a different answer.
 

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I had the 0D and 0C codes come in one time I was running with precats disconnected so I figure that code means the DME is seeing something out-of-range with the sensor output. INPA said "short circuit to ground or value too small". The fuel trim code 90 is driven by the lambda integrator going to the limit trying to correct for a high or low O2 sensor reading. The 57 I'm not so sure about but maybe the DME is seeing the post-cat go out of sync with the pre-cat.

The fix is pretty easy so why not try it?

OP, has anyone disconnected/reconnected the bank 1 O2 sensors recently? I seem to recall that they give these codes if they are connected together instead of to the DME.
 

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Interesting thoughts on the MAF swap, can anyone confirm that a bad MAF would indeed affect both banks? Anyway, perhaps I should have mentioned that the car has a Powerchip Gold 93 Tune, has 157K mi. and I don't think the O2 sensors have been changed, and I have not changed the plugs. I got it with 93K mi. Injector and cylinder head cleaner are on the way. Car idles well at start-up 95% of the time, since this started 2 months ago, and clears after a few stabs on the throttle or restart if stumbling, pulls hard although perhaps has lost a bit recently from 2.5K to 3.5K rpm. Seems, and it may be imagined or road vibration, to have a slight engine vibration in this range, like the fuel trim or air mix is a bit out of wack. O2 sensor(s) is easy so may replace. Seems like a vacuum/air leak would happen more frequently or constantly. Also, would a bad injector cause multiple cyl. misfire codes? I've gotten codes from all bank 1 cylinders over the last few weeks, seems that 3 or 4 are acting up at the same would be a fuel delivery issue. Will tighten intake tubes and do a smoke test tomorrow. Additional thoughts? Thanks again.
 

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Interesting thoughts on the MAF swap, can anyone confirm that a bad MAF would indeed affect both banks?
I understand you asking for other opinions but the MAF thing is pretty obvious. You have two MAF's measuring air flow in each air tube into a COMMON plenum that's shared by both banks. Only if the air flow through a MAF was dedicated to one bank would a swap be useful.
 

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That is a deceiving video. They are only smoke testing the ICV system and once you get that far I can inspect the elbow faster than they can hook up. If the elbow is good then hook up the smoke tester, but no smoke will come out the injector seals even if they are bad. They leak under vacuum usually. You will have a valid neutral test but a ton of things only leak under vacuum.
 

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Thanks Sailor, agree. I think my Indy smoked it thru the intake and as I said it was leaking from somewhere under the plenum. Have not yet, but will have to pull it to see more.
 

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I had the SES light flip on and idle went to crap while I was sitting at a light. No warning, just instantly bad idle.

I threw the following series of codes:
1B 27 DM-TL switching valve
88 136 Idle speed controller
72 114 "Exhaust camshaft VANOS position control, Cyl #5-8"
E8 232 Evaporative emissions purge valve functional check
AF 175 "Air-fuel adaptation, Cyl #5-8"
D1 209 "Misfire during warm-up, Cyl #5"
D2 210 "Misfire during warm-up, Cyl #6"
D3 211 "Misfire during warm-up, Cyl #7"
D4 212 "Misfire during warm-up, Cyl #8"
D5 213 "Misfire during warm-up, multiple cylinders"
FC 252 "Intake camshaft VANOS moving time, Cyl #5-8"

Given this is a whole bank, am I safe to assume it's a MAF?
 

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No it is not the MAFs you have several problems. 1B is not a code when it comes first, it means to use table 18 for reference, unless it showed 1B twice in a row. Even though 88 could cause idle problems, it might be there because of a reaction to the 72 and FC. The 72 and FC are likely responcible for most of the codes and that is the vanos solenoid board. There are quite a few DIYs posted on the board for repair. Pretty simple even at lower skill levels.

First thing you should do is clear the codes and see what comes back first, second etc. Start it and if the idle is off read the codes. Then drive and read the codes etc. Don't reset the codes after you do it once. Some codes take time to appear It would not surprise me if you have a bad vanos board and dirty idle control valve. Both are common. Are you going to fix this yourself or take it to a shop?
 
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