[snacks]

Trouble codes from a WIFI reader and OBD Fusion app:

Confirmed:
P1415

Pending:
P17F6
P17E3

First one comes up as being the "Secondary Air Injection System Bank 1"

The others are Ratio Monitoring Clutch errors.

These all popped up after I changed the MAF back to my original one (more on that later), all injectors and a fuel line. Could this be related in some way to the transmission issue? These things don't seem related at all, but it's also suspect that the car was shifting fine before I made these repairs and suddenly it's bad right after I worked on it.

After I first discovered the trans issue, I cleared the codes then unhooked the battery for a couple hours. Drove 100% fine for about 5 minutes and then the issue came back. The car WILL shift into R after a couple tries, but once the red gear of death shows up, it feels like I'm stuck in first.

Backstory:

I swapped the MAF many months ago after the car developed a rough idle - just weird pulsing revs right after starting up and at stop lights. Eventually had a CEL, code said it was MAF, so I changed it using a used part, and nothing was improved. At the time, I didn't have a chance to keep chasing the issue so I just dealt with the rough idle for a while. My guess is the used part was bad.

Fast forward to last weekend - I was noticing a gas smell for a couple weeks, so I did some research, found that it might be the connection of the line at the fuel rail, which it was. I also have a ticking under the hood and read that it might be a bad injector. I happened to stumble upon a used fuel rail, all injectors and the hose I needed for $50, so I bought it.

My car has 220,000 miles on it so I figured it wouldn't hurt to swap out all the injectors and I hoped it might fix my tick issue as well.

While I was working on everything else, I also cleaned and re-installed my old MAF sensor that I saved. Surprisingly, THAT issue was gone.

I put it all back together and the car fired up just fine. Gas leak was fixed, car was running good, but I still have the tick so I guess it's a lifter.


I ran it through a car wash (5 minute drive) then went to Oreilly (across the street from the wash) and that's when it had the transmission issue for the first time, so it was pretty much immediately after I got everything put back together.

The ONLY thing I can think of that might relate this issue is that I maybe accidentally messed up some wiring when I was pulling the new fuel line from the top of the engine to the bottom of the car. Is that a possibility?

Maybe the MAF is still bad too somehow - is the MAF or air injection system related to the transmission in any way?

If this requires a transmission replacement or rebuild, I've got a 2006 325i for sale - $2000 OBO.

[Fritzer]

I don't think that the Mass Airflow Sensor would affect how the transmission chooses when to change gear. Likely something when you were putting in the new Fuel Rail, unrelated to the function of the part though. I would say you could have knicked something that is sending weird signals to or from the transmission. Has the ""lifetime"" transmission fluid ever been changed/serviced?

[hassmaschine]

Is this a US 325i? I don't think they have SAP - in the US, that was only on the N51.

'ratio monitoring clutch' sure sounds like at transmission problem. the MAF can't cause your transmission not to shift, I think that's unrelated.

[snacks]

Originally Posted by Fritzer

I don't think that the Mass Airflow Sensor would affect how the transmission chooses when to change gear. Likely something when you were putting in the new Fuel Rail, unrelated to the function of the part though. I would say you could have knicked something that is sending weird signals to or from the transmission. Has the ""lifetime"" transmission fluid ever been changed/serviced?

As far as I know, the fluid has never been changed. I haven't done it and I don't know the history of the car before I bought it 4 years ago.

I'm thinking my best bet is to take it to a good independent BMW shop and get it diagnosed. I'd gladly pay $100 or whatever to a have it be only a messed up wire instead of whatever a trans costs.

[snacks]

Originally Posted by hassmaschine

Is this a US 325i? I don't think they have SAP - in the US, that was only on the N51.

'ratio monitoring clutch' sure sounds like at transmission problem. the MAF can't cause your transmission not to shift, I think that's unrelated.

It is US. I have read that elsewhere about the SAP. I'll have to do some more searching on that code.

[Fritzer]

Originally Posted by snacks

As far as I know, the fluid has never been changed. I haven't done it and I don't know the history of the car before I bought it 4 years ago.

I'm thinking my best bet is to take it to a good independent BMW shop and get it diagnosed. I'd gladly pay $100 or whatever to a have it be only a messed up wire instead of whatever a trans costs.

Yeah take it to an independent place to get it properly diagnosed, this is an odd one. Be careful though, some places are really shiesty and will try to inflate the problems your vehicle has to squeeze as much as they can out of you. Inversely some places are amazing and help you out a ton. Just gotta choose the right place.

[hassmaschine]

Originally Posted by snacks

It is US. I have read that elsewhere about the SAP. I'll have to do some more searching on that code.

I'm 99.9% sure you don't have SAP, only the SULEV N51 had it here. Could be emissions related, but generic P-codes don't really tell you the whole story on a BMW.

Anyway, that's a red herring. The other two codes point to your real issue.