[nnpa2]

Hello community!
I am brand new to the BMW world and very recently took possession of a 2007 328i n93 with 120k miles. I have absolutely no service history on it, only an honor system from previous owner that it was "well taken care of". Unfortunately, although good intentions of what he stated, I think that term to him it meant consistent oil changes since I immediately noticed on the drive the suspensions were out of wack, tires were subpar, ride was just harsh so I knew suspension work needed to be done. Over the last few years it was seldomly used, so it most likely didn't get to operating temps very much.

When I first drove it, it seemed fine at first for a few days but after 5ish days of driving it around 500 miles, it ultimately it started to rear its issue with idling (when stopped at a red light or stop sign and also parked at my garage after a few minutes, doesn't happen right away on cold start). Idles fine at start (seems to be normal at 600 rpms), and sounds normal, but after seconds of normal idling comes spurts where it would hesitate or surge (if that's the right term) where it goes down rpms slightly, at the same time this happens, I feel rough vibrating throughout the car from the engine and hear "grumbling" that coincides with the rpms dipping down. It does it for a few moments and if I wait long enough of it doing this, sometimes the engine cuts off with some dash warning lights but sometimes it keeps doing this rhythm and doesn't cut the engine off.

I have a maddox obd2 reader (just bought it for this purpose) and it doesn't give any codes.. What's weird is I can be driving a long stretch of road that doesn't have any lights or stop signs or hop on the freeway and it drives absolutely fine, no engine sputter or grumbling in rpms or feel that the engine is struggling. Only when at a stop or park is when the issue surfaces. I also did a road test and when I was at a red light, when it started revving down after 10 seconds or so, to test, I switched to N and was revving the engine to at least 1k and it seemed like the engine was happy as long as I kept my foot around 1k or more. It did NOT down rev or sputter or die on me.

Link to video (starts at 24 second mark, I was trying to replicate it by moving from N to R to D, but testing it today, seems to happen on any gear as long as I let it idle at the normal 600 rpm range): https://1drv.ms/v/c/2e067524bd76350e..._PjGM?e=WigIaw

In order to attempt to fix myself, (I'm NOT a mechanic, I just learn from youtube university, and just do maintenance on my cars like fluids and do basic repairs so this is out of my experience!). I've done the following from researching the last few days on similar symptoms I found on this forum to try:
-Replaced valve cover from Autozone (had evidence of the infamous issue of gasket from dried oil all around the cover and in the spark plug well)
-Replaced plugs with NGK 6619
-Fresh oil change (coincidentally I did the oil change within the 2 days I had it and the idling issue started happening around the 6th day after that.. not sure if related or just pure coincidence..)
-Cleaned MAF sensor
-Replaced both engine and cabin filters to paper (previous engine filter was K&N "lifetime" filter, ugh...I hear bad things about the oil and how it messes up with MAF sensors.)
-Cleaned vanos solenoids 2x (was not dirty)
-cleaned vanos check valves 2x (screen wasn't too dirty IMO compared to some other videos I've seen)

Each one of the things I did above, I did sequentially, and tested right after and it did not help or improve.

What I am going to attempt to do on my free time the next few days that are remaining:

-Replace coils (I didn't do this as I've owned 4 cars, 1 of them past 200k and I've never changed coils, only plugs for maintenance. Didn't think the probability of it being bad was high so I ignored this but I can be wrong.)
-Vacuum leak test using a funnel and tube to listen for any hissing sounds
-Clean throttle body/intake manifolds

Just wanted to ask the community if there's anything I can focus on that is more targeted to the issue I'm having since time is a little limited to tackle everything under the sun (I still other maintenance items I have to change such as coolant/ATF/Diff, shocks/struts etc but I'm pushing those items off until I fix the idling issue so I can at least make it drivable or at least reduce the anxiety that this will die on me) or luckily if someone has spotted from what I've stated above, knows exactly where to pinpoint me to, that would be helpful! Thanks in advance community!

[TunafishE93]

Could you freeze frame data when the car dies with your maddox obd2. See if you can pinpoint a problem.

[nnpa2]

Originally Posted by TunafishE93

Could you freeze frame data when the car dies with your maddox obd2. See if you can pinpoint a problem.

Ah ok, yes I see that feature on the reader. I have not played around with that but I'll learn it and reply back on what I find. I just used it to try and read any codes but haven't tried any of the "advanced" stuff on there.

[nnpa2]

Originally Posted by TunafishE93

Could you freeze frame data when the car dies with your maddox obd2. See if you can pinpoint a problem.

does freeze frame even work without throwing a code?

[gbalthrop]

Originally Posted by nnpa2

does freeze frame even work without throwing a code?

NO. Freeze Frame Data is a "Snapshot" of system parameters at the moment a Fault Code was SAVED. If NO fault code, NO FF Data.
George

[NZE90]

I think you need a better code reader. You say that warning lights appear on the dash. If that's the case, there is definitely fault codes stored. I think ISTA would be a better option in your case.

When you did the oil change, did you notice if your central oil filter cage was present, and did you replace both the o rings?

[nnpa2]

Originally Posted by NZE90

I think you need a better code reader. You say that warning lights appear on the dash. If that's the case, there is definitely fault codes stored. I think ISTA would be a better option in your case.

When you did the oil change, did you notice if your central oil filter cage was present, and did you replace both the o rings?

Sorry, the warning lights I stated above, it wasn't the check engine light or service soon light. It was something else, and I know when I put the code reader to it, there was no codes. I'll try to have my phone ready and capture the lights that come on. Usually when it happened is when the engine sputtered and quit.

[nnpa2]

Originally Posted by gbalthrop

NO. Freeze Frame Data is a "Snapshot" of system parameters at the moment a Fault Code was SAVED. If NO fault code, NO FF Data.
George

that's what I thought, was asking in case someone knew something I didn't when it came to operating these odb readers

[nnpa2]

Originally Posted by NZE90

I think you need a better code reader. You say that warning lights appear on the dash. If that's the case, there is definitely fault codes stored. I think ISTA would be a better option in your case.

When you did the oil change, did you notice if your central oil filter cage was present, and did you replace both the o rings?

Ah yes, i saw that recommendation from another thread. I checked and it was there and I did replace both the o rings. When I pulled the cap, the filter came with it so that was supposedly a sigh of relief since I did notice the filter didn't come off the first time i took the cap off. The filter used before was a K&N. I switched back to the mann filter

[gbalthrop]

Originally Posted by nnpa2

... 2007 328i n93 with 120k miles... after 5ish days of driving it around 500 miles, it ultimately started to rear its issue with idling (when stopped at a red light or stop sign and also parked at my garage after a few minutes, doesn't happen right away on cold start). Idles fine at start (seems to be normal at 600 rpms), and sounds normal, but after seconds of normal idling comes spurts where it would hesitate or surge...
sometimes the engine cuts off... with some dash warning lights but sometimes it keeps doing this rhythm and doesn't cut the engine off.
I have a maddox obd2 reader (just bought it for this purpose) and it doesn't give any codes... I can be driving a long stretch of road that doesn't have any lights or stop signs or hop on the freeway and it drives absolutely fine...
Just wanted to ask the community if there's anything I can focus on that is more targeted to the issue I'm having...

I've looked at your video. It appears highly likely that at idle (perhaps when system voltage is LOWER than it is at > 1,000 RPM) there is a complete Ignition or Injector Pulse "Shutdown" for a few milliseconds. If that is the case, RPM drops suddenly (all cylinders quit firing) & when ignition/injector pulse is restored, there is sudden RPM increase. "Misfire" on one or two cylinders would NOT be as sudden, but WOULD likely cause a misfire fault.

I'm NOT familiar with you Maddox Scan Tool. Apparently there are ~ 4 different models. Your MSV80 DME is capable (using INPA or ISTA) of identifying one or more cylinders that are "running rough" if fueling or spark issues are local to one cylinder. A simple $5 to $8 Spark Tester would indicate if spark is interrupted on that cylinder. Move tester to other coil/plug connections & see if other cylinders are similarly affected. Listening to Injector "Click" with an $8 Mechanic's Stethoscope, or even a long-handled screwdriver, Socket Extension, or old Jackhandle. You COULD have an issue with Fuel Delivery (fuel pump operation). Can your Scan Tool read faults in EKPS (Fuel Pump Module) fault memory?

Rather than run out & spend MORE money on new tools, or worse yet: throwing parts, I would suggest identifying TESTS you can do to "drill down" on what is causing the issue, using what you already have. There are MANY possible things that can cause a momentary "cutoff" of DME function. Some of those possible things would NOT set a fault code. If your problem progresses (gets worse), you MAY reach a point where the engine stalls, but won't ReStart.

Questions:
1) Last-7 Characters of your VIN? Changes in JB (Junction Box) Fuse Panel & E-box (under hood) contents as of 3/1/2007.
2) Make/Model of any Scan Tool or diagnostic software (INPA/ISTA) available?
3) Do you have a simple (~ $10 at HFT or Amazon) Multimeter?
4) Do you have a Spark Tester? ($5 to $8 at HFT).
5) What are your CC-ID codes?

When you have a "!" next to the Gear Selected in the Lower Instrument Cluster display, that means you have one or more CC-ID codes. Use the "Check Control" procedure found in your Owner's Manual to retrieve those codes. If you don't have a paper manual, you can download a pdf duplicate here (Free):
https://www.bmwusa.com/owners-manuals.html
George

[nnpa2]

Originally Posted by gbalthrop

I've looked at your video. It appears highly likely that at idle (perhaps when system voltage is LOWER than it is at > 1,000 RPM) there is a complete Ignition or Injector Pulse "Shutdown" for a few milliseconds. If that is the case, RPM drops suddenly (all cylinders quit firing) & when ignition/injector pulse is restored, there is sudden RPM increase. "Misfire" on one or two cylinders would NOT be as sudden, but WOULD likely cause a misfire fault.

I'm NOT familiar with you Maddox Scan Tool. Apparently there are ~ 4 different models. Your MSV80 DME is capable (using INPA or ISTA) of identifying one or more cylinders that are "running rough" if fueling or spark issues are local to one cylinder. A simple $5 to $8 Spark Tester would indicate if spark is interrupted on that cylinder. Move tester to other coil/plug connections & see if other cylinders are similarly affected. Listening to Injector "Click" with an $8 Mechanic's Stethoscope, or even a long-handled screwdriver, Socket Extension, or old Jackhandle. You COULD have an issue with Fuel Delivery (fuel pump operation). Can your Scan Tool read faults in EKPS (Fuel Pump Module) fault memory?

Rather than run out & spend MORE money on new tools, or worse yet: throwing parts, I would suggest identifying TESTS you can do to "drill down" on what is causing the issue, using what you already have. There are MANY possible things that can cause a momentary "cutoff" of DME function. Some of those possible things would NOT set a fault code. If your problem progresses (gets worse), you MAY reach a point where the engine stalls, but won't ReStart.

Questions:
1) Last-7 Characters of your VIN? Changes in JB (Junction Box) Fuse Panel & E-box (under hood) contents as of 3/1/2007.
2) Make/Model of any Scan Tool or diagnostic software (INPA/ISTA) available?
3) Do you have a simple (~ $10 at HFT or Amazon) Multimeter?
4) Do you have a Spark Tester? ($5 to $8 at HFT).
5) What are your CC-ID codes?

When you have a "!" next to the Gear Selected in the Lower Instrument Cluster display, that means you have one or more CC-ID codes. Use the "Check Control" procedure found in your Owner's Manual to retrieve those codes. If you don't have a paper manual, you can download a pdf duplicate here (Free):
https://www.bmwusa.com/owners-manuals.html
George

Thank you for the detailed reply! I am keen to trying those troubleshooting methods. Always looking to learn how to diagnose, if not this, for my other vehicles in my garage as they too get older! I will sheepishly admit since this is a 122k old car, I was ok with throwing parts, especially with the high mileage and the thinking that it needed to be done anyway but definitely will be down to get my hands dirty to diagnose. I already did buy 6x coils from FCP euro back a few days ago and is still slated to come in next week. I can always return or hold on installing till I diagnose. I can always send em back if it turns out my existing coils are still good and are not the problem.

The maddox tool I have is their most entry level one: https://www.harborfreight.com/mr5-18...der-70838.html. I was going to go out to swap to the bluetooth version since it was not much more and it can read transmission temp (helpful when I tackle the ATF fluid change soon after I fix this idle issue!). I don't see on the product specs or the manual anything about EKPS fault memory. Maybe that is a function of the more expensive scan tools.

VIN 7PX15038. I do have the cheap HF pocket multimeter. While I'm at HF I will pick up that spark tester, I dont mind adding more tools to my growing DIY garage. I take it as an investment in myself so I dont mind buying tools that are reasonable in cost.

Regarding the check control system, every time I try to access it, it just shows the yellow warning light bulb light. From my research, it's this light as documented from this article: https://yourbmwblog.com/bmw-light-bulb-warning-symbol/
Problem is, if it indeed is a lightbulb error, I knew the fog light was out, I had that on my todo list on this vehicle but I didn't think it would prevent me from accessing the rest of the check control system. I tried hitting the up/down or the BC button and its just stuck on that single warning light.