[oc123]

Hi all:

Been a lurker here and learned much from all. I have an 2008 N54 335xi that I have spent money on irrationally and need help to get to a happy ending. So here goes, in short form:

Bought car 2 years ago with 150k miles running fine. Took on project to replace oil pan gasket and rebuilt suspension. Previous owner replaced all mechatronics in transmission water pump, engine mounts, thermostat and radiator.

6 months later, car started running rough and going into limp mode. Visits to BMW Stealer and another Indie shop said the car needed $9k of work or be scrapped. So very long story short and out of an abundance of stupid persistence, I have replaced in the last year but kept at stock level:

- Both Turbos with Vargas OEM replacement turbos with oil and cooler lines
- Rebuilt index 8 injectors and had indie shop code them in
- Bosch coils & NGK plugs
- Pierburg boost solenoids
- Bosch boost and manifold pressure sensors
- Upgraded PCV and all associated pipes and hoses
- All 4 O2 sensors with Bosch OEM units
- Replaced throttle body with one from a well running but crashed car
- New BMW high pressure fuel pump and both fuel pressure sensors
- Verified charge pipe is not cracked

I have a basic code reader, have reset all adaptation values and recalibrated throttle. Car runs much better but still has shakes and vibration at idle, feeling like some misfire or air leak and throws Mixture Control and Cylinder 1, 2 & 3 misfire codes and occasionally gets the reduced engine output icon.

It seems I almost have replaced everything -- I know, shouldn't have thrown parts at it but I was stupidly stubborn -- so now I am not sure what else to do. Any advice would be greatly appreciated as to where else to look at. Also, thinking I should invest in a good diagnostics / coding set up to get reliable data. Any advice for a beginner?

Many thanks in advance!!

[e90yyc]

I don’t have any N54 advice other than to ask whether you’ve checked for carbon buildup?

Can confirm that you’ll absolutely want a good code reader or cable and software. Or dongle and app.

Cheapest route is a cable and the BMW Standard Tools suite of software which includes INPA and ISTA. You’ll just need a Windows laptop to run it.

Alternately, Foxwell (and others) make BMW-specific code readers. Under $200.

A few app/dongle options out there too.

Money well spent, and will allow you to read hex codes which can provide more specific information.

Best of luck! I’d hardly describe you as a beginner after having done all that work .

[gbalthrop]

Originally Posted by oc123

... 2008 N54 335xi... Bought car 2 years ago with 150k miles running fine... 6 months later, car started running rough and going into limp mode. Visits to BMW Stealer and another Indie shop said the car needed $9k of work... [invoices/diagnostics records/reports?]...
- Upgraded PCV and all associated pipes and hoses...
- Replaced throttle body with one from a well running but crashed car
I have a basic code reader, have reset all adaptation values and recalibrated throttle. [??] Car runs much better but still has shakes and vibration at idle, feeling like some misfire or air leak and throws Mixture Control and Cylinder 1, 2 & 3 misfire codes and occasionally gets the reduced engine output icon... thinking I should invest in a good diagnostics / coding set up to get reliable data...

Thinking, followed by discussion with others & then ACTION is usually good plan. DIAGNOSIS, before throwing parts should be 1st Action. You have other BMW's, so BMW Diagnostic Software is almost a No-Brainer. Both INPA & ISTA were available as free Downloads (MEGA) in the 2017-2022 timeframe, until BMW went on a tear & threatened legal action if not taken down. MANY folks still have the electronic files. Check around with any BMW clubs in your area for suggestions.

In your case, you really need to get & learn to use BOTH INPA & ISTA. However, just to get started dealing with your reported issues, we need:
1) whatever fault codes are currently present in the DME Engine Control Module. The specific codes, NOT the perceived 'Definitions', please. Use whatever Scan Tool you have available, AND, if there is a nearby Advance Auto, AutoZone, etc. that reads Engine fault codes FREE, please include those codes.
2) Please provide the Make/Model of your Scan Tool. Check its manual to determine if it can provide/display (as defined below in explanation of INPA Functions):
a) Freeze Frame Data;
b) Live Data;

INPA/ISTA:
1) INPA, one of BMW Standard Tools, is BMW 'Factory-Level Diagnostic Software. Its text & Labels are mostly in German, but Google Translate works well, & with Forum Help, you can get started quickly.

2) ISTA+ is BMW Dealer-Level Diagnostic Software, & includes Documents such as Wiring Diagrams & Repair Procedures, as well as "Test Plan", a Flow Chart type guided diagnosis, & it's in English.

3) If you have a Windows Laptop, only cost (if you can find software source) is ~ $50 for a K+DCAN Cable to connect Laptop USB port to OBD II Socket of vehicle.

4) BMW Diagnostic software Capabilities:
a) Read/Clear Fault Codes in ALL Modules of vehicle (NOT just Engine Module); E9x has ~ 20 different modules;
b) Read Freeze Frame Data, a 'Snapshot' of system conditions at the moment the Fault Code was saved, such as Engine RPM, Temp, Load, Mileage, System Voltage, etc.; Very Helpful in cases of intermittent faults.
c) View Live Data, such as values of INPUTS to a module, such as Temperature, Pressure, RPM, Engine Smoothness (Laufunruhe) by cylinder, spark advance, injector pulse duration, cam angles (VANOS), MUCH MORE;
d) Activations or Triggering of electrical components: pumps, motors, solenoids, lights, to test that component and the Output side of the Function of the Module which controls that component;
e) System Tests to test function of a system generally, depending upon engine, model, equipment installed.
f) ISTA has Documents, such as Repair Procedures, Torque Specs, Wiring diagrams with component locations & connector views for identification of Pins & Sockets, wire functions/ colors/ size, etc. In short, the best "Shop Manual" you can get. Just enter your 'Last-7 Characters of VIN' & you can view ALL, without being connected to vehicle.
g) INPA displays ‘History Memory’ in the PowerTrain Modules (Engine, Fuel Pump, Transmission, Transfer Case, DSC), which allows you to view Fault History, even AFTER regular Fault Memory (FehlerSpeicher) has been cleared. You can view the last 10 Fault Codes in the module, along with the mileage/km (to nearest 8km) when the last 3 instances of that code were saved. Since most folks don’t know that feature exists, it’s a good way to check prior history (& Owner Credibility) of Vehicle when “new-to-you”. You can CLEAR ‘History Memory’, but doing so suggests fraudulent intent or ignorance (your choice ;-).

E9x models are as much as 20 years old, & haven't been produced for > 10 years. Paying shop rates for maintenance & finding a shop that is competent in DIAGNOSIS is increasingly UN-sustainable. 'DIAGNOSE It Yourself' is the key to maintaining a 10+ year-old car on a budget.

Please provide your existing DME Fault Codes & answers to other questions about Scan Tool & its capabilities, as known to you. If you have any record of diagnostics performed by shop, including Fault Codes, please provide that (a scan) as well. We can then suggest next steps.
George

[E93Dude]

That was George doing a nice mic drop.

I support everything he said, but if you don't have a Windows computer or Mac running Parallels, a really good scan tool option in Protools. It runs on your smart pone or tablet (Android only, I believe), and connects to your OBDI II port with a dongle. Read codes, program new injectors & batteries, and a whole hose of other functions. Very easy to navigate, and is reasonably intuitive.

[oc123]

Thanks all for your replies, particularly George for the detailed response.

So for the BMW tools, are the results easy to interpret, like if I have a freeze frame of data, I still would need to understand what the diagnosis might be, correct? Do they require dealer tech training? I guess I have to do a google search for links to such software?

What are the drawbacks going with Protools vs BMW factory tools? I am keen to make an investment but want to pick a good one.

George, now I remember partly how I got here. When I took the car to the dealer and 2 Indie shops, they all insisted on following the factory diagnosis tree. They wanted to start with upgrading the injectors to index 12, regardless of the actual operational status of the installed index 8 units. Then the next step would be the HPFP and then turbochargers. That was before they would give any diagnosis. That was when I thought I would do the same parts replacement but at least without the shop markup. Back then, some error codes included 30FF, 29E0, 2A2E, 29F4, 29F5. Now most are gone except for 29E0, 29CD, 29CE, 29CF in any combo, but nothing from Bank 2 or Cyl 4, 5 or 6.

What I also saw from my limited code reader was that one of the O2 sensors post cat never changed from 0.34V when the other one moves around but I did not get any codes for shorted or malfunctioning sensors and I know they are new. That is why I am convinced I need better diagnostic tools.

[marvinstockman]

Are you saying the car only runs lousy at idle, as such, you could have a mechanical valve issue. You can trouble shoot this with a $10 vacuum gauge and a Youtube DIY.

[marvinstockman]

Forget what I said, as I missed what you said in your post. Anyway, keep the vacuum gauge in mind.

[oc123]

I am hoping with a good diagnostic tool I can capture vacuum (or pressure in this case) along with other parameters for context but I agree with your point, thank you.

[gbalthrop]

Originally Posted by oc123

... So for the BMW tools, are the results easy to interpret, like if I have a freeze frame of data, I still would need to understand what the diagnosis might be, correct? Do they require dealer tech training? I guess I have to do a google search for links to such software? What are the drawbacks going with Protools vs BMW factory tools? I am keen to make an investment but want to pick a good one...

I would suggest FIRST learning what your existing Scan Tool can do, and seeing how far you can get diagnosing your issues with it, WITH Forum Help. Trying to "Learn" the capabilities of a Scan Tool or Diagnostic Software (INPA/ISTA), WITHOUT practical application of diagnosing YOUR existing faults, is more esoteric/theoretical than helpful for most folks.

So first, please tell us:
1) Make Model of any Scan Tool available to you, & what fault codes are read by that Tool in your DME/ Engine Control Module.
2) Whether or not you have a written Manual explaining the capabilities of that Tool, & if so, whether the manual suggests, or you have determined how:
a) it can display FF Data for a DME Fault Code;
b) it can display Live Data showing INPUTS to the DME from sensors, buttons, etc.
c) whether or not you have a Multimeter. Don't need anything fancy, a $10 multimeter from HFT or Amazon is all you need.
With answers to those questions, we can suggest NEXT Steps you can perform with what you have available. Getting Fault Codes read at Advance Auto, etc. is an alternate approach.

Second Issue:
Before anyone can suggest what Tool/Software to move up to as a Second Step, we need to know:
1) Do you have a Laptop with Windows operating system, or even a desktop?
2) Do you have an Android Operating System phone (NOT an iPhone)?

As others have stated, IF you have no laptop, but have an Android OS Phone, you can get a "ProTool" license for $95. You will still need a Cable, Wi-Fi or BT adapter to connect your phone to OBD II Socket. See this LINK for details:
https://www.bimmergeeks.net/protool

Once again, BOTH INPA & ISTA were formerly found FREE online, & many folks have saved the electronic files downloaded from places like MEGA. If you are able to find someone with those files, all you need is a K+DCAN Cable for $30 to $50 (IF you already have a Laptop). Various vendors sell INPA/ISTA & ISTA comes in MANY configurations. AFAIK, there is currently NO LEGAL source of INPA/ISTA at any price. Last I checked, BMW wanted $2,800 per year for cloud-based TIS connection license.

There is NO "one-size-fits-all" solution to the Diagnostics issue. Everyone learns new subject matter differently. I have worked on my own cars & other equipment for 65 years (NOT a typo ;-) My approach has always been to try to understand HOW the system I'm working on is intended to work, & if it is NOT operating correctly, devise tests to determine WHY/what the actual fault is. Diagnosis of Electrical Faults (which most Fault Codes indicate) requires evaluation of the wiring diagram of the system in question, or specific steps suggested by a Forum Member who can interpret that diagram. ALWAYS ask for/ share Forum Help.

Others may want to know if someone else has ever had the same symptoms, & if so what did they do to "fix" it. Personally, I believe that is a HIGHLY FLAWED approach, as there are MANY things that can cause any one 'Issue' or malfunction. That approach often leads to Expen$ive/ unnecessary "Part$ Throwing".
George

[oc123]

Hi George,

Again, thanks for the continued guidance. I am going to break my responses up into more manageable pieces (for me anyways). So for first issue:

1) The scan tool I have is the Creator C310+. I bought it some years ago.
2) Either I lost it or it did not come with a manual. There is info on it on the web back to 2018.
a & b) I will attach a couple of screen shots so you see what some typical data screens look like. What I have found is the unit is very slow. Changing fields to read values takes a few seconds before the prompt even moves. I think it is a good basic code reader and first order verification of whether an O2 sensor is bad but not good enough for any real time diagnostics.
c) I have a couple of DMMs, a UNI-T UT89X and a Fluke 77, good enough for basic car electrical troubleshooting

[oc123]

Hi George,

Coming to Issue 2:

1) For personal use I have a 4 year old HP with USB and HDMI capabilities and recently upgraded to Win 11 so ought to be good enough, I think.

2) I have a Pixel 6 Pro phone and I have rooted Amazon tablets to sideload Android software. They all have WiFi and USB capabilities. I certainly would not mind investing in a "real" Android tablet like a Samsung to make it easy on my aging eyes.

I agree with your comments about the diagnosis approach. Now I have a bit more personal free time to really dig into the data to sort this out so I want to equip myself the right way.

Thanks again.

Ray

[oc123]

One question about ProTool -- I understand it can connect by wire USB / Ethernet to OBD port or WiFi / Bluetooth to OBD adapter. Since I am starting from fresh, is there a best option to go for? I will either use my Pixel phone or buy / borrow a Samsung tablet.

[BRG_N54]

Originally Posted by oc123

One question about ProTool -- I understand it can connect by wire USB / Ethernet to OBD port or WiFi / Bluetooth to OBD adapter. Since I am starting from fresh, is there a best option to go for? I will either use my Pixel phone or buy / borrow a Samsung tablet.

Any approved OBD2 to USB will work. I think I got mine from Bimmerlink years ago, looks kind of like this one from Amazon. When using with ProTools I have a USB A-USB C adapter.

I'm old and prefer a wired connection, but there are Bluetooth options out there also.

[StradaRedlands]

Originally Posted by oc123

One question about ProTool -- I understand it can connect by wire USB / Ethernet to OBD port or WiFi / Bluetooth to OBD adapter. Since I am starting from fresh, is there a best option to go for? I will either use my Pixel phone or buy / borrow a Samsung tablet.

I have both the BG cable as well as their Bluetooth adapter. I use the adapter 99% of the time.

[gbalthrop]

Originally Posted by oc123

...
1) The scan tool I have is the Creator C310+. I bought it some years ago.
2) Either I lost it or it did not come with a manual.
c) I have a couple of DMMs

See attached manual pdf for your C310+.
I would suggest experimenting with it (Can't hurt anything when you are just viewing screens). You're just viewing either data saved in memory (Fault Codes), or "Data Stream" or Live Data, which are inputs to that Module (such as the DME/ Engine Module), from sensors. Your 2008 335xi has ~ 20 different Modules in it. You might see how many of those you can connect to, other than the DME, & make notes of HOW you accessed each, & what fault codes are currently present in each.

However, for purposes of solving your current issue (rough running & Lean fueling?), you/we need to know the following:
1) What Fault Codes are currently present in the DME? Any beside 29E0 & 29E1?

2) What Data Stream "Parameters" or values can you view? Your 2nd photo shows:
a) Bank 2 Pre-Cat O2 Sensor Signal;
b) High Pressure Fuel System pressure;
c) Low Pressure Furel System pressure;
d) Exhaust gas temp.
e) What other parameters/values can it display, such as Intake Air Temp, Boost Pressure, Intake Pipe Pressure, Pre-Cat O2 Sensor Signals for Bank 1 (cyl. 1,2,3) & Bank 2?

3) What are Last-7 characters of your VIN?

4) What performance issues are you experiencing? Does it accelerate properly at wide open throttle? Does it idle smoothly & at what RPM?

5) What warning lights appear on Instrument Cluster if you let engine idle for 5 minutes after cold start?
George

[oc123]

Hi George,

I do not see the pdf manual for C310+ attached but I am sure I can find it online.

The last drive, after I had cleared codes with the code reader, after 15 or so minutes, came back with 29CD, 29CE, 29CF, 29E0 and 29E1 codes after CEL was turned on.

The car idles with vibration, like it is missing, hesitates on acceleration, particularly during partial throttle. At WOT, it has power but one can tell it just is not smooth, if that makes sense. It idles at between 750 and 800 rpm.

The reduced engine output light would come on during some drives. The codes after that were the same as what I have now.

[gbalthrop]

Now attached, C310+ Manual pdf. Sorry.
George

[oc123]

Originally Posted by gbalthrop

Now attached, C310+ Manual pdf. Sorry.
George

Much obliged, George

[lookalikehuuh]

Can I ask about some of the parts that have gone into the car?

I am specifically interested in the rebuilt index 8 injectors... Where did you source them? The direct injectors on these cars have had HUGE issues and often leak/fail. I suspect this is the top reason why all the shops you took your car to wanted to replace the injectors first with known.

I would like to suggest something to you that I don't believe has been mentioned above. MHD is a tuning program that can be loaded on both IOS and Android devices and is normally used for tuning your car, however, It also has the ability to check BMW specific codes for your car (although it doesn't offer freeze frame data I don't think). It DOES however allow you to log a bunch of really important factors like Air Fuel Ratios that you can then upload to datazap.me and can help us figure out what is going on.

Recently I actually had mixture control codes on my car. It turns out the oil cap on my car wasn't sitting properly and was causing unmetered air to enter the crankcase causing idle to be crap, and the car to occasionally stall. I ended up figuring out that it was the oil fill cap by smoking the PCV system. After a few minutes I was able to see the smoke coming out of the oil filler cap.

In your case it might not be as simple, but good luck!

It could be as simple as a bad/loose pcv connection or as bad as a bad set of injectors that the DME is unable to properly control flow thru.

[oc123]

[QUOTE=lookalikehuuh;31857646]Can I ask about some of the parts that have gone into the car?

Hi, thanks for your thoughts.

Regarding the injectors, I bought a refurbished set from Vader Solutions. An Indie shop coded them in for me but I guess I should DIY that part in the future.

I did not look at MHD -- was not looking at tuning but did buy Protools. Now I am trying to learn it and do what you mentioned.

An interesting clue to me is that the misfire codes on my car always happen on Cyl 1, 2 & 3 or the whole Bank. Looking forward to do some data logging to find out why.

[oc123]

OK, an update after a bit of time with Protools:

Since I had not driven the car for a while, I had to charge the battery. I cleared the codes and started looking at Live Data. After idling for a while (I cannot drive the car far since the tag has expired and I cannot renew the tag without passing emissions) in my garage, codes 29E0 and 29E1 were logged. I looked at a bunch of data but what stood out was the Lambda Probe Resistance after Bank 1 and Bank 0 both displayed 0. Occasionally Bank 0 would pop up 256 and go back down to 0. I looked the the Lamba Probe Resistance before Bank 0 (Bank 1 not listed in the tool) and it showed 256.

Both sensors post Cat have been replaced with OEM units so should be good but 0 just does not sound right. What other causes could be there -- wiring? DME? Anyone have any insights before I dig into the belly of the car?

[oc123]

So I am reading online about probe resistance. It seems, from another forum, that there is this term dynamic resistance and that the probe resistance is displayed in steps of 256 up to 1024 being normal. Was able to find a menu to display the lower bytes of the values. They are non-zero so looks like no shorts.

Then I set up gauges to monitor voltages from O2 sensors pre & post cat on banks 1 & 2. Pre-cat values on both banks were rather stable around 2V at idle. Post-cat on Bank 2 was stable at 0.8V but Bank 1 was jumping from 0.1V to 0.8V. Could this indicate I have an air leak in Bank 1?