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Discussion Starter #1 (Edited)
I've been hunting this for about 4 months when I started noticing more soot on bank 2's exhaust tips.

INPA readout remains this way, even after swapping the MAF with bank1 (adaptations reset in between swaps).

MAFs (029 Bosc) < 1 year old
Pre-Cat O2 < 1 year old

This doesn't seem like a vacuum or ail leak related to the intake, since results are only affecting bank2.

My question is: Is this reminiscent of an exhaust leak? Is this where I should concentrate my efforts? From exhaust manifold down to the O2 bung area?

Thanks for any help. I'm hoping for a smoke test at my indy this week, but still wanted some knowledge before I went in to talk with him.
 

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Do you have a code? Do you have an X-pipe? You are calling it lean and the adaption looks like it is adding fuel and the exhaust pipe says rich. That sounds like something is lying and the only thing that comes to mind is the O2 sensor. Think that exhaust leak is a good guess and worth looking at.

The O2 senor bungs crack, many have had that problem, good place to start. Do you have any idea how to find an exhaust leak? Do you have a compressor that the air pressure can be controlled?
 

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Discussion Starter #3 (Edited)
I am stock aside from Tubi Rumore cat back. I agree the INPA is confusing, correcting for what it believes is lean and adding fuel when it shouldn't. I have to visit my Indy for a smoke test where he will drop the exhaust.

I cleaned the area around the bungs with some polish and 0000 steel wool, but could not see any visible cracks or pinholes.

I could swap the o2 sensor and see if the pattern follows it. I hadn't thought the sensors would misread but it wouldn't surprise me.

Thanks, sailor
 

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I doubt it is the sensor. I have little faith in InPA, I see where it contradicts my scanner. The way it reads then reports fuel trims is confusing. If you have a Tubi then you likely have an X pipe. When you have a X pipe the exhaust from both banks is mixed. I could not explain why one side would be different than the other.
 

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Even though there are two maf sensors on the car, they are not read as bank 1 maf and bank 2 maf, the DME sums their readings to get total air consumption. So swapping them will have no impact on bank specific trims.

I recently had fuel trims about where yours are, but on both banks and I had soot on my tailpipes. I replaced all the cam position sensors and the trims came down from 1.08/1.11 multiplicative to around 1.02/1.04. I don't know how old your CPSs are but one bank may be lying to the DME about the cam position which is causing the fuel trims to be what they are.

Other than that, I agree that it could also be O2 related. I have a Rogue X pipe and noticed no change in fuel trims after install. The factory exhaust had a H pipe in it anyways downstream from the cats near the center support.

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Discussion Starter #6
I doubt it is the sensor. I have little faith in InPA, I see where it contradicts my scanner. The way it reads then reports fuel trims is confusing. If you have a Tubi then you likely have an X pipe. When you have a X pipe the exhaust from both banks is mixed. I could not explain why one side would be different than the other.
There is no x-pipe. It's stock cats and resonator, just the tubi rumore cans and connector fittings. I had read a thread about an x-pipe causing problems, but this just crept up about 4 months ago. It's pretty strange but I'm hoping a smoke test proves something. I just read 3 threads here about cracks around the o2 bungs, even hairline cracks can make a large difference.
 

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Discussion Starter #7
Even though there are two maf sensors on the car, they are not read as bank 1 maf and bank 2 maf, the DME sums their readings to get total air consumption. So swapping them will have no impact on bank specific trims.

I recently had fuel trims about where yours are, but on both banks and I had soot on my tailpipes. I replaced all the cam position sensors and the trims came down from 1.08/1.11 multiplicative to around 1.02/1.04. I don't know how old your CPSs are but one bank may be lying to the DME about the cam position which is causing the fuel trims to be what they are.

Other than that, I agree that it could also be O2 related. I have a Rogue X pipe and noticed no change in fuel trims after install. The factory exhaust had a H pipe in it anyways downstream from the cats near the center support.

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Man, if did't just spend $600 on 2 tps and 4 cps in the past month, I was thinking something similar related to CPS. I even re-cleaned my vanos solenoids. So what you're saying is, in INPA, the multiplicative 1 and 2, aren't associated with a bank on the vehicle?

I should pull the plugs on both sides and check for extra soot as well.

Thanks for all the suggestions.
 

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No the multiplicative trims are, but the maf sensors are not bank specific. I was reacting to your earlier post where you said you swapped your mafs from side to side with no change in behavior.

Yea if you have new CPSs I'd say you can disregard my suggestion. A cracked O2 bung would definitely give you the symptoms you are seeing.

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Discussion Starter #9
No the multiplicative trims are, but the maf sensors are not bank specific. I was reacting to your earlier post where you said you swapped your mafs from side to side with no change in behavior.

Yea if you have new CPSs I'd say you can disregard my suggestion. A cracked O2 bung would definitely give you the symptoms you are seeing.

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I see what you're saying, that's why the maf swap did nothing. There must be some type of leak downstream.

Once I get a diagnosis, I'll report back. I believe he is dropping the exhaust, sealing it up and pumping smoke through under pressure, so it might take a couple of hours to complete.
 

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01 Carbon/Silverstone Exhaust: Jedders-HJS high flow cats-resonator delete-Xpipe-Eisenman cans
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Your multi 2 of 1.12 says your are adding fuel long term trim. The lambd integrator and add values being normal means it is a minor issue that the DME is able to correct for. The lambda probe voltage being low doesn't help.... those values fluctuate from high to low every couple of seconds.
This could be an exhaust leak but also could be a bank specific air leak, at the throttle body gasket, or a vacuum line. Have you checked the infamous plastic elbow?
 

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Discussion Starter #11
Your multi 2 of 1.12 says your are adding fuel long term trim. The lambd integrator and add values being normal means it is a minor issue that the DME is able to correct for. The lambda probe voltage being low doesn't help.... those values fluctuate from high to low every couple of seconds.
This could be an exhaust leak but also could be a bank specific air leak, at the throttle body gasket, or a vacuum line. Have you checked the infamous plastic elbow?
I haven't pulled the plenum yet, but I did replace both the FPR hose, the infamous #17 elbow as well as the throttle body flange gaskets within the last 3 months.

I'll have to check those again. The flange gaskets went on without a hitch, but you never know.

You're right, I did a pnt-screen and there are quite a few moving items on the screen. I can run it again and wait to capture if you think I got data in transition. I captured this after the car was running for and hour on the freeway with the a/c running if that makes a difference.
 

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01 Carbon/Silverstone Exhaust: Jedders-HJS high flow cats-resonator delete-Xpipe-Eisenman cans
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It might be helpful to watch INPA while someone else is driving, see if you notice anything else going on.

I am wondering if the stock resonator mixes bank 1 and 2 exhaust, like an X-pipe? If so, having soot only on drivers side exhaust tips would indicate a post-resonator issue. Otherwise it could be anywhere along bank 2, intake, exhaust, even fuel.
Do you have any misfire codes?
 

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Discussion Starter #13
It might be helpful to watch INPA while someone else is driving, see if you notice anything else going on.

I am wondering if the stock resonator mixes bank 1 and 2 exhaust, like an X-pipe? If so, having soot only on drivers side exhaust tips would indicate a post-resonator issue. Otherwise it could be anywhere along bank 2, intake, exhaust, even fuel.
Do you have any misfire codes?
I don't have a single code aside from the rain sensor, which works, but still throws a code. I will have to remove the plenum. First I figured anything under there would affect both banks, but the flange gaskets could be a direct feed of an air leak.
 

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This could also be a bad injector. One that adds normal fuel at low demand but does not have the flow at high demand. Or something else with an injector they often fail in ways one would not suspect. I did one not too long ago that was perfect to a little low at idle and even on the test bench at lower bandwidths but as soon as the bandwidth came up it just stayed open and dumped tons of fuel in.
 

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Discussion Starter #15
This could also be a bad injector. One that adds normal fuel at low demand but does not have the flow at high demand. Or something else with an injector they often fail in ways one would not suspect. I did one not too long ago that was perfect to a little low at idle and even on the test bench at lower bandwidths but as soon as the bandwidth came up it just stayed open and dumped tons of fuel in.
I hadn't thought of the injectors at all; good point. If no leaks are found otherwise, it might be time to have these sent off for examination and cleaned.
 

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That's why I mentioned fuel but it would be a clogged injector to make the dme add fuel. And doesn't explain soot only on one side unless there is no X pipe. It appears the stock E60 resonator has a stock X or H component but I can't find anything on the E39.
 

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Discussion Starter #17 (Edited)
That's why I mentioned fuel but it would be a clogged injector to make the dme add fuel. And doesn't explain soot only on one side unless there is no X pipe. It appears the stock E60 resonator has a stock X or H component but I can't find anything on the E39.
A fouled O2 sensor, or otherwise contaminated, would cause this type of condition? Overly rich?
 

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A fouled O2 sensor, or otherwise contaminated, would cause this type of condition? Overly rich?
Yeh fouled O2s usually read lean but yours are newish so shouldn't be the culprit although getting overly generous with the anti-sieze is a possibility. Would be simple enough to have a look.
 

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Discussion Starter #19
Yeh fouled O2s usually read lean but yours are newish so shouldn't be the culprit although getting overly generous with the anti-sieze is a possibility. Would be simple enough to have a look.
I've had sensors in the past that needed anti-seize, but the ones I ordered came with some already on the threads so I skipped adding any. I'll take a look at it before tonight.
 

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Discussion Starter #20 (Edited)
I wanted to update this as I finally got a smoke test. The test showed the #5 cyl gasket flange leaking slightly. I removed the plenum, replaced the IAC T connector and the hose that goes to bank2, replaced the purge valve while I was there, removed and reseated the flange gaskets. The groove in the throttle bodies need to sit EXACTLY with the ridge in the gasket rounds. They can sometimes slip out as you tighten the clamps (strange they are round clamps on a non-round shape). I ignored the TIS advice to lube the rubber pieces with vaseline before installing, this caused them to slip all over the place. I reset adaptations and now show my multiplicativ at 1.04 and 1.05. I've only got 25 miles of mixed driving, so I'll be driving more tomorrow and this week to get a good amount of mixed miles.

I am contemplating the RK plenum plates as they are a superior design, even though they cost more (current OE are $102 each).

Thanks for all the suggestions.
 

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