[Glowin]

Since these maps aren't beta, I assume it's ok to post my questions here.

I've been having hiccups during acceleration when car is warm, where the car is not accelerating smoothly at all, and I see the AFR's around 18 at that point in time, and then jump to below 15.

I've managed to take a video of it, most noticeable in first gear from a stop. And I was only boosting like 5 PSI!

But I've had shuddering in a third gear WOT pull tonight as well (didn't get it on a log though), where the same thing happened with the AFR's. It happens sometimes when I go from a cruise to moderate acceleration, but it also happens after shifting from first, and then while accelerating in second, first goes super lean, then rich.

Didn't have any issues with the 6-16 maps on f/w 16, which I might just switch back to so I can rule that out.

Car is:

2008 335 6MT - MSD 81 on fairly recent BMW firmware 2.37
12,000 miles on it
Stock, other than Procede
91 Octane always

Car has no issues accelerating smoothly without Procede installed, or with Procede in valet mode.

Here's a video of it:

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And here are some logs. Should I be logging some other channels instead?

Could it be an HPFP on its way out? I'm getting some weird throttle closure it seems, is that part of the problem?

No codes at all when scanning with the Procede BTW.
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[OpenFlash]

What happens at full throttle? Your actual throttle is barely open in those pulls which is probably why you aren't seeing AFR stay on the rich side. The real test would be to see what happens at full throttle. If it goes lean at high rpm, then you have a fuel system problem.

Shiv

[Glowin]

Thanks. Will try and report back results. A few questions please:

1 - Is it ok to just do the test in first and second gears, or you want 3rd gear WOT pulls?

2 - Why does the DBW throttle not match the actual one though? I thought that was something you addressed long ago so we don't have the DME inducing throttle closure?

3 - By fuel system related, you mean the HPFP could be suspect? That sucks as I had it replaced just last year (first one) so now only 7,000 miles have passed since it was replaced. And if that's the cause, I'd just have to wait for it to die, or is there a solution?

4 - Can driving the car like this cause any damage to the engine or other parts? Should I switch to valet mode unless I'm testing things, til we get this figured out?

[Glowin]

Originally Posted by shiv@vishnu

What happens at full throttle? Your actual throttle is barely open in those pulls which is probably why you aren't seeing AFR stay on the rich side. The real test would be to see what happens at full throttle. If it goes lean at high rpm, then you have a fuel system problem.

Shiv

YGM Shiv. Tested at full throttle, didn't go lean. Logged AFR and fuel pressure for you.

[Clap135]

My car doesn't stutter and I have no issues, however I mentioned this part throttle lean condition before. I simply don't care if there no real boost I side the manifold, I don't want it going over 15ish personally.

[vase330]

Why don't you guys upgrade to the latest firmware & maps and see what happens? Not like they are going to go back fine tune old stuff. If you were talking about latest ones I can understand, but you are wasting time on old maps/firmware not going to help you or anyone else.

[Clap135]

I am always on the latest maps and firmware.

[Glowin]

Sorry if I didn't mention it, but the second round of testing I did was on latest firmware and maps.

I most notice it as clap said in partial throttle, especially going up hills, in 2nd gear. Maybe right after I change from 1st to 2nd. It will go lean like 17 to 18, and stay there for a second, accompanied by rough acceleration, then go rich. I've sent the details to Shiv via email. Doesn't happen during WOT.

As an aside, for that second while it's lean, considering how often it is happening, is it bad for the engine?

I don't want to keep driving the car like this if it's bad for it, and would rather switch to valet mode until it's figured out, and only go to map 1 for testing.

[OpenFlash]

Glowin-- emailed you back

Clap135&Glowin-- The procede AFR gauge will display the leaner of the two wideband AFR readings (every time it samples, it pics the leaner of the two values). So if you have a faulty o2 sensor that is slighty more lazy to respond, it will show up on the gauge. One thing that would be worth doing (and I emailed this suggestion to Glowin), is record a lean condition while logging both wideband AFR banks. Then afterwards, compare the two banks and see if they are similar. They should be very similar. If one reads consistently leaner/reacher than the other and is noticeably slower to respond, it's likely that the sensor is failing.

But before you go replacing sensors, one thing you can do is reset your lambda and AFR adaptions which you will be able to do with the Procede very shortly (next update). Until then you can use a BT tool to to do this. See if that helps.

Really no harm in having these short term lean spots during load changes at partial throttle/partial boost. But if they are resulting in drivability issues, then it's a problem that should be fixed as it can get worse with time.

Shiv

[Jeff@TopGearSolutions]

On my last car which was non direct injection, some tuners would tune partial throttle to 16AFR for lean cruising around town. Giving those circumstances, I doubt 16-17 AFR on partial throttle is a big deal on a direct injection car, as we know you can run a little more lean on DI vs Non di. Just my .02.

[vase330]

Originally Posted by JPSlick

On my last car which was non direct injection, some tuners would tune partial throttle to 16AFR for lean cruising around town. Giving those circumstances, I doubt 16-17 AFR on partial throttle is a big deal on a direct injection car, as we know you can run a little more lean on DI vs Non di. Just my .02.

A gram of rat poison won't kill you either; Maybe have a mild stomach pain, so I dout its really harmful. So my .02 cents says a little rat poison every now and then is ok since it wont kill you and cause any major damage....

Sorry JP, couldn't help. Not commenting on the lean AFRs, as I am a complete noob. Just a bit of harmless humor. Ofcourse I am taking it that JP is no expert on this, and really just saying he should not offer advice or conjuncture, hope its understood.

[Glowin]

Originally Posted by shiv@vishnu

Glowin-- emailed you back

But before you go replacing sensors, one thing you can do is reset your lambda and AFR adaptions which you will be able to do with the Procede very shortly (next update). Until then you can use a BT tool to to do this. See if that helps.

Really no harm in having these short term lean spots during load changes at partial throttle/partial boost. But if they are resulting in drivability issues, then it's a problem that should be fixed as it can get worse with time.

Shiv

Hey Shiv, how's the update coming along for being able to reset the adaptations? Any better timelines? I've turned off the Procede since the car's really not driveable in the city because of these lean issues and the stuttering/shuddering it induces in partial throttle... It was getting really jerky at times. I really miss all the boost!

[Glowin]

Clap, where are you at with your issues? My fuel pump's fine, as are my O2 sensors, so the adaptations are next as far as possible culprits, but I don't have a BT tool, so I have to wait for the updates...

[Clap135]

My car runs fines. I never had issues. I just noticed the lean part throttle af downlow. Never affect my car though.