Bmw 3 series E46 fault codes

[Reubenguzman]

Hello, I have a 2004 bmw 325i (auto) and I am experiencing some exhausting issues, my car will only commute in emergency 3rd and 4th gear and it goes into limp mode when I really get on the gas like getting on the freeway for example me accelerating to keep up with speed will throw me into limp mode I was told to replace ignition coils and spark plugs and that should resolve the issue but it didnÂ’t my car also shakes quite a bit at higher speeds and it will rev up super high before it shifts and when it does finally shift its super hard and erratic even when slowing it feels like itÂ’s slamming down in gears IÂ’ve also been experiencing quite a bit of smoke when driving the car for quite a bit (grey smoke). I recently scanned the car (before replacing ignition coils and spark plugs ) and I had 3 cylinder misfires p0300, fault codes for my MAF p0102, ambient air temp sensor circuit p0070, and intake air temp sensor 1 circuit p0113, and then a random code p16A7, any thoughts ? Thank you so much for your time

[shogun]

welcome here, I will move your thread to the E46 forum

[MarcoZandrini]

It looks like your MAF may be at the root of your issues. You car has a MAF that not only measures the mass of the air being sucked into the engine, but also the air’s temperature. Does the gauge cluster ambient air temperature readout show the outside air temperature or does it show -40* or 122*? This sensor’s data is used by the automatic climate control module (IHKA). The sensor (it’s located in the cavity between the left front tire inner fender and the front bumper) can be easily replaced.

What tool are you using to scan the engine computer (DME in BMWspeak)?

[Reubenguzman]

Hey thanks for reaching out. I’ve already replaced the ambient air temp sensor and it did help with the idle of the car in a way but for some reason fault codes are still coming back for it my dash reads neither -40 or 122 it just shows how many miles due the oil change is. I scanned the car with just a regular OBDll scanner from auto zone

[dworthy]

So to see if the MAF is truly the issue, unplug it and see if the car runs better.

If it does, I would look at getting the intake smoke tested at a professional shop to see if you have any vacuum leaks. There are times where MAF codes will populate and not be the problem.

[Reubenguzman]

The car does run better with the maf unplugged

[dworthy]

That tells me that there is nothing wrong with the MAF, you have a vacuum leak.

[MarcoZandrini]

The intake manifold needs to be professionally smoke tested. You need to find a reputable indie shop that specializes in bimmers. Try www.bimrs.org.

[Reubenguzman]

Update just got my car back from the mechanic he’s saying it’s my whole ccv system causing my issues he smoke tested and this is the only spot smoke is coming out of, this is my first bmw so I’ve never heard of anything like this being caused by a ccv valve is this a common issue ?

[MarcoZandrini]

The E46 CCV was designed by an engineer who’d been fired by Audi. /s Fir some reason modern bimmers have issues with the CCV system. The E46 CCV is especially bad. Btw, the upper hose on the CCV body gets a ton of vacuum as it’s hooked indirectly to the intake manifold.

[Reubenguzman]

I’ve seen other posts on here where people resorted to a catch can system would that be a good/ reliable idea in my case ?

[dworthy]

A catch can will mean more maintenance on your part, as you will have to check it every month or so. Typically the OEM system lasts 10 years, so if you replace it with the same stuff from BMW, you can expect it to last the lifetime of your ownership unless you plan on keeping the car for longer.

[Reubenguzman]

Thanks for the feedback I think I’m gonna install a whole new ccv system I will post my progress

[MarcoZandrini]

Lasts 10 years?? Darin, you’re being (very) generous!

I installed a catch can on my old 2001 330Ci. Mounted it in the drug bin on the passenger side of the engine compartment. Ran the hose behind the cylinder head. Reduced oil consumption but if I had to do it all over again I think I would have tried the 24 hour piston soak first. This uses AC Top End Cleaner, and then added the 02pilot mod.

[dworthy]

That's about how long I had the original in the wagon, and upon opening the original one, it was still good at 10 years funny enough. Now the hoses are a different story as they were brittle and breaking apart as I replaced the valve.

[carsonyounge46]

Hi, I have a 2002 325ci automatic, I have misfire with low fuel codes on all cylinder and system too lean in bank one and two, I’ve replaced the mass air, fuel pump, and fuel filter, additionally I’ve checked my ignition coils, I’m out of ideas on what it could be, any help is appreciated

[Reubenguzman]

Update: I replaced ccv and the car still is running the same in the regular automatic but if I put it in the sport mode it’s a lot more responsive I haven’t went to go get it scanned yet but basically my question is what’s my next step? My best guess is clear my codes and see what comes back

[dworthy]

Yes, clear the codes to see what does come back. Just make sure you record all the codes before clearing them.