[bimmerquick43321]

Originally Posted by refugeeofwar

Getting crank power is easy. You simply hook a engine dyno up to the flywheel before putting the engine in a car.

yeah not sure where my head was lol, it's not like I'm not watching some of those "Power Nation" shows were after building an engine they plug the engine to a sort of dyno.... drugs are bad.... lol

[refugeeofwar]

Originally Posted by mecbain

yeah not sure where my head was lol, it's not like I'm not watching some of those "Power Nation" shows were after building an engine they plug the engine to a sort of dyno.... drugs are bad.... lol

rofl

[chris82]

Originally Posted by TheSt|G

Indeed. In my setup it absolutely induced drone. I am running Euro intake w/ the Euro BMW Performance intake which is pretty rare however.



No, but I also only had it on around the block. Even if it gained 5-10hp, that's not something you are likely to feel. Want it?

*Edit* Hell, you are local. You can try it before you buy it if you want.

Sending a PM

[fravel]

Originally Posted by tetsuo111

Bummer - I'm thinking our MAFs are hyper delicate. I'm running with SES and error codes pointing to the MAF and rich AFR. But haven't yet changed the MAF to see if it clears the SES because the car runs fine, other than at start up during cold idle and pressing the brake, the motor rpms surge.

Originally Posted by tetsuo111

Related question - at what point does a new tune become necessary? For instance, w/o a tune, the DISA manifold is pointless. Wondering if the DME is intelligent enough to adapt to the new AFR's, or would new maps be even more beneficial? hassmaschine?

You've piqued my interest with this. I have similar mods on my 330i, (Eurobox, RM hose, PE w/secondary cat delete) and I have been struggling with fuel mixture codes for about 6 months (2A2E and 2A2F). My indy has confirmed that the car is running pig rich, but can't find any actual problems with the car that would explain it. I've been wanting to get a tune, but have been holding out until I can sort out this problem.

I know the stock tune is already on the rich side, but I'm starting to wonder if getting the engine tuned for my mods could potentially fix the problem?

[ZeroSum]

nice man

[Taskmaster]

Originally Posted by fravel

You've piqued my interest with this. I have similar mods on my 330i, (Eurobox, RM hose, PE w/secondary cat delete) and I have been struggling with fuel mixture codes for about 6 months (2A2E and 2A2F). My indy has confirmed that the car is running pig rich, but can't find any actual problems with the car that would explain it. I've been wanting to get a tune, but have been holding out until I can sort out this problem.

I know the stock tune is already on the rich side, but I'm starting to wonder if getting the engine tuned for my mods could potentially fix the problem?

Sounds like there is a problem, and a adding a tune to it will not correct that issue. Check and clean the MAF and also depending on miles, you might want to start considering replacing the O2 sensors.

[hassmaschine]

the stock 328i tune is not rich at all - it is actually very lean, except at high RPM when cat overheat protection kicks in, then it goes rich. If you are getting mixture codes it's got to be something wrong, the stock tune won't do that on its own. I don't know how susceptible to vac leaks the N52 is but that might be something to consider in addition to the O2 and MAF sensors.

as far as the tune adapting to mods - sure, it will always try to reach the target lambda in the stock tune, but the point is the target lambda itself is what needs to be optimized for better performance.

[fravel]

Originally Posted by TheAxiom

Sounds like there is a problem, and a adding a tune to it will not correct that issue. Check and clean the MAF and also depending on miles, you might want to start considering replacing the O2 sensors.

MAF is new
Plugs/Coils are new
VANOS solenoids are new
Air filter is new
PCV valve and hoses are new
DISA valves are both new
Smoke test revealed nothing
Fuel pressure is good

2 different shops have both told me the O2 sensors seem a little 'lazy', but neither recommended changing them because there aren't any O2 sensor specific codes. All I've got is 2A2E and 2A2F (fuel mixture control, bank 1 and 2, respectively). Nothing seems to have an effect on it, and the only symptoms are an occasional hiccup at idle and the SES on my dash. Considering how much money I've put in parts for "likely suspects" that ended up fixing nothing, I'm hesitant to swap more parts that I'm not 100% positive have failed.

Originally Posted by hassmaschine

the stock 328i tune is not rich at all - it is actually very lean, except at high RPM when cat overheat protection kicks in, then it goes rich. If you are getting mixture codes it's got to be something wrong, the stock tune won't do that on its own. I don't know how susceptible to vac leaks the N52 is but that might be something to consider in addition to the O2 and MAF sensors.

I'm in 330i, is the stock tune the same? The most recent shop I went to identified that the car was definitely running rich.

Originally Posted by hassmachine

as far as the tune adapting to mods - sure, it will always try to reach the target lambda in the stock tune, but the point is the target lambda itself is what needs to be optimized for better performance.

That's what I'm asking.. could a tune potentially change the target lambda? It seems to me that my car is getting way more air than the stock tune expects, so it's dumping fuel to compensate.

[hassmaschine]

330i tune is also on the leaner side although not as much as the 325i/328i.

if it was getting more air than it was measuring, it would be running lean. It would run rich if there was less air than it was expecting.

it doesn't "dump fuel" - it only targets lambda 1.0 (except at WOT). So if it's really lambda 0.9 or worse, it still thinks its 1.0 but something has gone awry with closed loop operation.

Sometimes what will happen is it's trying to lean it out to compensate for the actual problem, but there is a maximum value for the fuel trims (such as +/-25%), and since it can't compensate any further it continues to run rich.

[fravel]

Forgive my dumb questions, I'm just trying to understand how this all works and I wasn't clear about what I think might be happening.

I think the car is measuring the air coming in accurately (ie, not excess air because of vacuum leak), I think the car just has no idea what to do with the extra airflow from my mods and in turn, it's putting in more gas than it needs to because it doesn't know how much to give to begin with. Is that possible?

So then the answer to tetsuo's (and my) question is that a tune couldn't possibly help? Is there a point at which the physical components of the intake/exhaust system have been modified such that a new tune is required to get the engine to run properly?

The car is running rich and there are no clear reasons from a component failure standpoint. ~138k miles

[hassmaschine]

no I don't think so. It always knows what to do with more air - it will always, always, always try to reach the lambda 1.0 target from the part throttle maps, and the slightly richer lambda targets for the full throttle maps. If it's measuring the air correctly then it would know how much fuel to add. these cars also have widebands so it knows exactly what the lambda feedback is.

fuel trims being maxed out seems likely to me. There might be a clear reason, but I don't think it is your mods. the stock tune is lean, not rich..

[fravel]

And maxed out fuel trims, considering what I've already changed coupled with my mileage, likely points to bad O2 sensors?

[hassmaschine]

if it's running rich, and the fuel trims are maxed out, that means it's trying to lean it out to reach lambda 1.0 but it can't. It doesn't necessarily mean O2 sensors. But I would consider them and the MAF as suspect.

[fravel]

MAF is new and my indy is quite confident that it's working properly. Guess we'll try sensors.

[rick100]

this may be a stupid question and unrelated question but does the AA headers remove the O2 sensor? .

[hassmaschine]

no

[Dan Bilzerian]

Originally Posted by hassmaschine

no

Have you measured/recorded to get the Lamda feedback?

[hassmaschine]

on what? In reference to my answer, you can't remove the primary O2 sensors from an N52 powered car. They are more important than the MAF sensor.

[fravel]

Originally Posted by TheAxiom

Sounds like there is a problem, and a adding a tune to it will not correct that issue. Check and clean the MAF and also depending on miles, you might want to start considering replacing the O2 sensors.

So, I noticed in the AA tune thread that back in Feb. you mentioned cam timing might need changed with large changes to intake/exhaust flow. I've gone ahead and ordered new O2 sensors, but now I'm back to wondering about tunes.

[Taskmaster]

Originally Posted by fravel

So, I noticed in the AA tune thread that back in Feb. you mentioned cam timing might need changed with large changes to intake/exhaust flow. I've gone ahead and ordered new O2 sensors, but now I'm back to wondering about tunes.

Those changes are for power, not for the car to run properly, but I think the O2 sensors are problem.

[fravel]

Originally Posted by TheAxiom

Those changes are for power, not for the car to run properly, but I think the O2 sensors are problem.

So... the O2 sensors weren't the problem

Still completely baffled by this.

[hassmaschine]

There are delay time settings to account for the distance from the exhaust valve to the O2 sensors. This would certainly need to change on headers, as it would typically be longer/further away - I often wondered if the tuners were addressing these. I wouldn't be surprised if they didn't.

O2 feedback is incredibly important on the NG6 platform - the widebands give basically real-time feedback to the fuel control algorithm, which is highly model based, and any discrepancy in the model (such as the distance from the exhaust valve to the O2 sensor), could certainly cause issues like this.