Loss of power

[boots]

yes that's correct the exhaust gets louder and will drone. I ad this happen twice also. The difference is I did not restart my car. The first time I drove back home. Later on after about 70 miles it went back to normal. The 2nd time I just kept driving as I said fuck it and found some more roads to terrorize. Just in a slow way. LOL It reset after 140 miles. Pain in the ass, but if it happends again, I will pull over and give the restart a try.

[dhirm5]

I don't get why you guys run the catless DPs if this hassle comes along with it. Wait for a proper tune and run cats for now.

[mstmng]

Originally Posted by dhirm5

I don't get why you guys run the catless DPs if this hassle comes along with it. Wait for a proper tune and run cats for now.

once u go black u never come back
u cant imagine how intoxicating it is
trust me, this hassle is worth the smile u get ear-to-ear every time u drive this car

dont let Dave see your comment

plus this tune doesnt seem promising.. GXX M5 will come out before we gonna see proper tune

[boots]

Some guys with the catted verson has had the same problem. Whether they report it on the open forum is on them, but I won't snitch them out to anyone due to respect. A tune is no guarantee that it will be out. I wont put one of those so called piggyback things that are out yet on my car. But as Grigory just stated, the sound of a catted or catless car is badazz. No complaints here.

[Tylerstar]

Totally worth the power and sound. Im spinning in 3rd, LOL . The downshifts will scare the shit out of people.

[mstmng]

Originally Posted by Tylerstar

Totally worth the power and sound. Im spinning in 3rd, LOL . The downshifts will scare the shit out of people.

I am spinning when i change from 3rd to 4th
Mental car!

[boots]

G your spinning while sitting at the Red light. You can't help yourself.

[dhirm5]

lol - ok - so primarily for the noise then. mine spins through third without any issue - the power is there regardless. hell in this winter weather i can break the tires loose by flooring it in fifth. not that the dps don't add to it...

[boots]

I really like my dp. Everyone said it sounds mean. Inside is quite until you get down. Totally different from just having straight pipes. Personally I think it sounds so much better than e60m5 w dp

[dhirm5]

Originally Posted by boots

I really like my dp. Everyone said it sounds mean. Inside is quite until you get down. Totally different from just having straight pipes. Personally I think it sounds so much better than e60m5 w dp

I'd totally do DPs if these power loss/cel issues weren't there. I hate the idea that the potential of the motor is restricted by these cats.

Just waiting for someone to crack the ECU then it's on.

[boots]

Yea where are those guros who hack the country's secure sites. We need them

[mstmng]

Originally Posted by boots

G your spinning while sitting at the Red light. You can't help yourself.

C'mon! Give me a break

[RPiM5]

Dudes,

I've written about this before and I'll write about it again. Some of you I've talked to about this personally. It doesn't matter if you have catted aftermarket downpipes or catless, it's the ECU's fault and not yours.

The ECU is basically trying to protect the cats when you are in a high air flow and high temperature situation. I've actually spoken with an engineer about this. It's the combination of the CEL light and the rear O2 sensors. The rear O2 sensors don't just sense O2 levels they also take temperature measurements as well. When the ECU starts to see high temperature readings from the rear O2 sensors on the downpipes it is programed to limit the output of the engine in order to protect the catalytic converters because the engineers designed it this way so that the cats aren't damaged and/or overheat and possibly catch fire. In the case of catless downpipes, the cats aren't even there to protect, but the ECU doesn't know this (again we need a real remap of the ECU), so that's why when one of these situations occurs, you will get the Drivetrain Malfunction on the iDrive:

1. You are driving along smoothly, and then all of a sudden slam on the throttle. In this case, you are causing heat to build up very very quickly in the downpipes in a very short amount of time. The O2 sensors sense this rapid change of temperature and airflow and again the ECU will cut the engine back to protect the cats.

2. You do a really long Wide Open Throttle/Full Throttle Pull up to the top of 4th gear. In this case, you are increasing heat and airflow steadily and right about when you get to the top of 4th gear or about 130mph the Drivetrain Malfunction occurs because the O2 sensors are now sensing that high temp level again. I've had this also occur in 3rd gear before so it's not just 4th gear.

Those are pretty much the only two ways that this Drivetrain Malfunction will occur with catless or catted downpipes. I've taken my M5 to the track with my catless downpipes and I've done numerous mountain runs without the DT Malfunction ever popping up, why? Because I was not putting my M5in either of those two conditions. Listen guys, just don't go mashing on the gas pedal all the time and you will be fine. Besides Greentrbo95gst has found a device that will take away the CEL consistently and therefore does actually prevent the DT Malfunction from popping up. You do have to have a CEL light for the DT Malfunction to occur because the ECU is then detecting that there is already something wrong with the Cat. I will be ordering this device soon as well, but I trust the testing that Greentrbo95gst has already done, so I know it will work.

In the end, it's just a minor annoyance, and there have been no proven long term affects from running catless downpipes. I've been running mine now for almost 15,000 miles and have had no serious problems. All you are doing with catless downpipes is relieving the pressure behind the turbos which is a very good thing. It does change the Air/Fuel ratio, but if we didn't have a sophisticated self-adjusting ECU then we might have problems, but we do and it's fine. The only other thing to worry about is just the attraction of unwanted or undesired attention, like from LEO or something. Most of the time I find the general public hates it, while a few enthusiasts that we run into love it.

Also a note about the E60 M5. I thought that depending on the exhaust you have on the E60 M5, running catless headers can sound amazing as well. I think both the E60 M5 and the F10 M5 running without cats sound equally insane. Just that one has a unique F1 sound and the other has a unique Ferrari-ish sound to it. I've heard examples of both cars where the E60 was running with catless headers but a soft exhaust and the F10 was running catless downpipes and a soft exhaust, and they both sounded tame still. The type of exhaust you have really matters as well.

Bottom line is that the ECU in the F10 M5 is extremely intricate and takes the inputs from many sources and thousands maybe even millions of calculations are done every second to the engine. The rear O2 sensors don't only sense O2 readings, and heat but are also used for the fuel logic of the engine itself and this affects so many other variables. Although the Air/Fuel ratio will be off when you first put on catless downpipes, the ECU can and does adjust for the removal of the cats and that's why we see big power gains in the mid range, it's just that some other aspects of the original ECU programming aren't adjusted for the removal of the cats.

[gmd2003]

Originally Posted by boots

Some guys with the catted verson has had the same problem. Whether they report it on the open forum is on them, but I won't snitch them out to anyone due to respect. A tune is no guarantee that it will be out. I wont put one of those so called piggyback things that are out yet on my car. But as Grigory just stated, the sound of a catted or catless car is badazz. No complaints here.

I've got the 200cell SS DP's ( the highest flowing catted ) and have never had the drivetrain malfunction . I did get an emissions CEL for only one bank so it is really close to passing emissions too . Damn California emissions makes US cars more strict than European models lol . SS is sending me their microcats spacers for free which will def take care of the issue for me since in so close to making the ECU happy with the HJS cats. Our secondary cats only measure emissions and temp . They are not involved in the closed loop AFR calculations the primary sensors are . The primary 02 sensors are the only ones that are wideband. Any solution to "turn off " an emissions CEL involves programming the ECU to see a fixed " in the green" voltage value from the secondaries . I've proven this with data logging on my supercharged Z4M ,and my tuned E63 M6 .

[boots]

These spacers you are referring. They should move the sensor further away so the 02 sensor is not reading so much air flow right in turn does not allow a cel. Am I somewhat correct?

[gmd2003]

Originally Posted by boots

These spacers you are referring. They should move the sensor further away so the 02 sensor is not reading so much air flow right in turn does not allow a cel. Am I somewhat correct?

They actually have catalyzers in them as well , so the sensor sees fuel and temp levels like stock .

[Tylerstar]

Totally forgot about that subject RPI. Come to think of it, I shut down for about 5 minutes to let her cool. After that It felt like I got all my boost back lol. Mainly happens in 3rd gear.

[boots]

Yes to what Dave said. Those two situations are what caused my lights to go crazy. And both times were when I was on my way to tape video for him. Drats! I returned home from being gone awhile and drive the car. The sound of my car was just music!

[EM1]

Got RPI catless downpipes and CAN tool from BM put on 2 nights ago and have gotten the drivetrain malfunction to come on 3 times so far. simple shut of ignition and turn back on fixes the situation but CAN tool is not stopping the problem.

[EM1]

All 3 were set off under full throttle once in 3rd gear and twice at top of 4th gear.

[EM1]

Ok, got some codes. Maybe you guys can help me decipher.

482BAC regulated differential lock, DSC function: not available

48002C ICM, ACC:interface DSC

480113 DTC button permanently pressed