Reduced Engine Power - Faults 2A98, 2A99 and 3100

[febul]

I was driving home about a week ago and noticed a kind of "rattling" noise upon acceleration coming from the engine bay. I pulled over and took a look under the hood, but didn't notice anything out of the ordinary. It drove fine for the next ~150 miles.

But, the next day as I was driving my car went into limp mode - reduced engine power with the half-engine light. Also smoke was coming out of the exhaust as I gave it throttle. Now almost immediately after driving the car goes into limp mode.

My car has about 49,000 miles. I am getting codes 3100, 2A98, and 2A99. (I'm also getting 2C77 and 2C31, but this is due to my catless downpipes.)

I took my car to BMW and even though I made my service advisor aware that my car had catless downpipes and was throwing 2C77 and 2C31 because of it, he continued to scan my car just to tell me that they can't do anything until they clear the DP-related faults. He also charged me an hour of labor ($150 >.<)

I've decided to just go the DIY route and try fixing the problem myself. What would cause 3100, 2A98 and 2A99? And how can I fix it?

[Solo_M_Tech]

Sounds like blown turbos. Smoke from the exhaust (blown turbo seals) rattle noise (wastegates or bad turbo bearings) Limp mode (all of the above). I would swap back to stock down pipes if you can and try to get the turbos replaced under the extended warranty.

[febul]

Originally Posted by ApexResistance

Sounds like blown turbos. Smoke from the exhaust (blown turbo seals) rattle noise (wastegates or bad turbo bearings) Limp mode (all of the above). I would swap back to stock down pipes if you can and try to get the turbos replaced under the extended warranty.

I just bought the OEM downpipes, they should be coming in a few days.

I don't see how my turbos would blow like that. :/ The previous owner told me that they were already replaced under the extended warranty.

[Solo_M_Tech]

I had a friend here in Germany get his turbos replaced by the dealer and a couple weeks later the new turbos failed. It's completely possible.

[PawlyGuNNz]

There could be different reasons my car is FBO was running 4gal of e85 mixed w 93 and my trims were too high were maxing out so my car three the 2a98 code 3100 low boost and limp mode... Also I prob need to replace my vanos solenoids....I reduced my ethanol content and my car is running normal again I need flash tune to run more e85

[febul]

Originally Posted by PawlyGuNNz

There could be different reasons my car is FBO was running 4gal of e85 mixed w 93 and my trims were too high were maxing out so my car three the 2a98 code 3100 low boost and limp mode... Also I prob need to replace my vanos solenoids....I reduced my ethanol content and my car is running normal again I need flash tune to run more e85

Well I'm stock other than catless downpipes and mids.

What could I do to isolate the issue?

[PawlyGuNNz]

I would replace vanos solenoids, how long have you had catless downpipes for? Do you have down pipe fix? Could also be carbon build up, coil, spark plug or injector....

[febul]

Originally Posted by PawlyGuNNz

I would replace vanos solenoids, how long have you had catless downpipes for? Do you have down pipe fix? Could also be carbon build up, coil, spark plug or injector....

I bought the car last year July with the catless DPs installed. I'd say it's been running catless DPs for at least a year and a half.

The previous owner did have the BMS DPFIX installed, but I removed it with intentions of taking it to the dealership late last year.

Is there anyway to inspect the VANOS solenoids/injectors to know if they're bad?

[PawlyGuNNz]

That's one of your problems right there you need to re install downpipes fix... Then I would take out the vanos solenoids... Clean them or blow oil out w compressor... Swap intake w exhaust since they are interchangeable ....

[febul]

Originally Posted by PawlyGuNNz

That's one of your problems right there you need to re install downpipes fix... Then I would take out the vanos solenoids... Clean them or blow oil out w compressor... Swap intake w exhaust since they are interchangeable ....

Alright I'll give it a try.

Why do I need to reinstall the DPFIX? I read that leaving it in messes with the AFR.

I've been driving without it for at least ~1.5k miles, since November of last year.

[PawlyGuNNz]

You can pm me if you want... Dp fix will allow you to run catless dp without error codes... Since your car went into limp mode it's throwing all the codes... You either do fix or oem dp sometimes you can run catless dp without fix but eventually you will get check engine light

[PawlyGuNNz]

Was just researching could be camshaft bearing ledges in your case w those codes good luck