[maarzz]

I have been noticing this strange symptom on my car and have not been able to pin point what it is. Full disclosure, I have not really put in much effort to isolate the issue either.
I first noticed it when a friend brought it to my attention while we had swapped cars in winter since his was an X-Drive. He said your car shudders and stalls when I tried to push it. I laughed him off and said you probably have forgotten how to drive a stick now that you have an automatic!! But then several months later, when I floored it in 6th gear for some reason (some fast car must have passed me), the entire car shuddered it felt as if it would stall. I eased off the pedal and depressed it more gradually and this time it went up the revs no problems... So I just ignored it since no fault codes came up on the OBC. Fast forward a couple of years, and now the issue is a lot more pronounced and required me to be very careful with the throttle... as long as I compress the pedal smoothly, there is no issue, but if push it and get aggressive, the entire care judders and on occasions the heck engine light come up and it starts running very very rough. The rpms stay stable though and there is no fluctuation of the needle. Today, a spirited hell-cat driver pulled me into a small traffic light Grand Prix and rest is history.. check engine light on, does not go away (in the past it went away when I switched off and restarted Ted) I barely made it to my destination and back home by taking back roads so I did not get stranded on the highway. I know a long post, but I would greatly appreciate any suggestions or tips. This is a bone stock car, and I am going to do some upgrades to it now since I have had it for nearly 11 years now and I am not afraid of messing anything up since it's residual value in $$ is nothing but sentimental value for me is priceless considering the memories I have around it. Thank you in advance.
P.S. I am not a professional mechanic but fairly handy with automobiles. I recently changed the oil filter housing gasket on it, upgraded the brakes, changed the torsion arm bushings and also diagnosed the fixed a broken ground cable that left me stranded 150 miles from home a few years ago..
also, looking for suggestions on upgrades for a first timer who is just starting to tune his 335i now..

[clegg]

I would run a bottle of Techron fuel system cleaner through it.

How many miles on the spark plugs?

[maarzz]

Originally Posted by clegg

I would run a bottle of Techron fuel system cleaner through it.

How many miles on the spark plugs?

I did the Techron a couple times and no noticeable difference! Also, I religiously use the detergent added gas from Mobil/BP/Shell but I will do the Techron again. I think I still have a bottle in the garage.
The spark plugs frankly I don't remember could be 25-30K. Since I never really did anything to the car engine this far, perhaps I should start with the spark plugs. Any suggestions on spark plugs? NGK? I do want to add a tune to it down the line (house extension might bump this off the priority list) so I am thinking of upgrading at least the spark plugs from the OEMs.

[Vania335i]

What are the codes stored in the DME?

[gunnerxq]

Broken growing cable?

[maarzz]

Originally Posted by gunnerxq

Broken growing cable?

Grounding Cable! Sorry, auto correct! Although, it was growing some oxidation goo on it
It was quite a process diagnosing it since there are no codes for it but pretty rewarding once I figured it out and then replaced it with a $5 diy grounding cable.. here is a friendly tip to anyone who may, god forbid, find themselves in a situation that the car suddenly stalls and then does not crank, take a spare jump cable and ground the engine directly ( I used the oil filter housing area), if it cranks then you have a ground issue somewhere... I found the cracked/fried cable under the driver side (watched a UK video and kept looking under the passenger side for 2 days )... or wait, was it the other way around? 🤔: well, you get the idea..

[maarzz]

Originally Posted by Vania335i

What are the codes stored in the DME?

I am ashamed to say but I don't know... 😔
I actually don't have access to a code reader right now. My old computer that had the INPA is lost and I cannot seem to make the file work on my Surface. Any suggestions on a source for the the INPA software?

[clegg]

You should be able to pull codes if the CEL is on with any code scanner. Most auto part stores can pull them for you.

[maarzz]

Originally Posted by clegg

You should be able to pull codes if the CEL is on with any code scanner. Most auto part stores can pull them for you.

So I got the INPA finally running and pulled the codes. Missfire in cylinder 5. I have a bunch of other codes too, but not sure if they are old.. will clear all and then see which ones come back. I am a bit technologically challenged, so not sure if the attachment will come through but I have tried to upload the screenshots here.

[maarzz]

Take-2, codes!

[gunnerxq]

Originally Posted by maarzz

Grounding Cable! Sorry, auto correct! Although, it was growing some oxidation goo on it
It was quite a process diagnosing it since there are no codes for it but pretty rewarding once I figured it out and then replaced it with a $5 diy grounding cable.. here is a friendly tip to anyone who may, god forbid, find themselves in a situation that the car suddenly stalls and then does not crank, take a spare jump cable and ground the engine directly ( I used the oil filter housing area), if it cranks then you have a ground issue somewhere... I found the cracked/fried cable under the driver side (watched a UK video and kept looking under the passenger side for 2 days )... or wait, was it the other way around? 🤔: well, you get the idea..

Thanks for the heads up. Yeah mine under the passenger rear wheel well is oxidizing pretty badly and this was 2 years ago. Have to look into it before the winter.

[maarzz]

Originally Posted by gunnerxq

Thanks for the heads up. Yeah mine under the passenger rear wheel well is oxidizing pretty badly and this was 2 years ago. Have to look into it before the winter.

So, happy to say that the issue is fixed; it was an ignition coil! The car got a new set of NGK spark plugs in the process and it ran so strong after this it felt like a totally different car even though it's completely stock by the way! Goes to say how poor it had been running thus far! So, for what its worth and if folks have a similar problem, keep in mind that once the DME detects a misfire, it shuts off that injector to prevent damage, AND this throws the naturally balanced inline 6 out of whack that then causes everything to shake! If you go under the car you can see the flywheel wobbling! For a moment I thought my flywheel failed and I started looking at single mass flywheels and clutch kits to replace mine.. luckily better sense prevailed, I downloaded the INPA, ran a few error test/erase cycles and narrowed it down to the faulty coil. Ordered it from Amazon, popped it in the car and it ran smooth with no CEL!
Now that I know my car is not dying, and it's pretty obvious I have done just the bare minimum to keep it running, I am going to spruce it up a bit...
First order of business was DCI's, arriving this week hopefully! Next in line is a charge pipe and my factory sports suspension is also ready to be replaced but the freaking B14s have been back ordered since last year so still holding out! Don't wanna go north of $1000 and I am not liking what BR Racing reviews..
Next on the shopping list is the charge pipe and intercooler and then perhaps some tuning, MHD?
Do share some pearls of wisdom since most of you have already treaded this path and learned from your experiences! Cheers and happy motoring!

[Smgs1992]

I think first order of business would be taking care of the rest of the maintenance. This clearly showed it was lacking for a basic ignition tune up. I’m gonna assume none of the gaskets have been replaced. No walnut blast or waterpump. What index are your injectors?

[maarzz]

Originally Posted by Smgs1992

I think first order of business would be taking care of the rest of the maintenance. This clearly showed it was lacking for a basic ignition tune up. I'm gonna assume none of the gaskets have been replaced. No walnut blast or waterpump. What index are your injectors?

The water pump was replaced a while ago, I wanna say 6-7 years ago, and so was the clutch! I'll have to check the injector index, but I have maintained the rest of the car myself.. regular oil change, recently did the oils filter housing gasket along with the coolant gasket.
Walnut blast has not been done, but I am looking into it it or perhaps some other way of decarbonizing the intakes. Another thing playing big time on my mind is the LSD conversion. Any thoughts on that?

[maarzz]

Originally Posted by Smgs1992

I think first order of business would be taking care of the rest of the maintenance. This clearly showed it was lacking for a basic ignition tune up. I'm gonna assume none of the gaskets have been replaced. No walnut blast or waterpump. What index are your injectors?

Hi, so I took care of some items.
1. Coils, upgraded to Eldor all 6
2.Spark plugs NGK irridiums
3.BMS DCI and Charge pipe
4. Injectors are: 2 are index 8 and 4 are index 2 😲
5. I am also upgrading to Myle HD track rods, sitting in my garage but not installed yet (the shop has stop adjusting my front alignment coz the track rod ends were rusted and they wanted to charge me a lot $$ to replace with some autozone kinda track rod ends so I decided to just get the Myle HD. Read few decent reviews about them.
6. The bilsteiin B14 kit is in order, but won't be here till Nov I am told...
7. AND the most ambitious purchase of all, vrsf 7.5" stepped intercooler...arrived but no idea when I will install it!
8. Oil catch can is here too..

Next on agenda is a tune, however I am confused between JB4 AND MHD or only MHD... I have not yet been able to figure out if MHD would function on its own or if I will always need to have the JB4. I am slowly getting up to speed with all the reading and researching so hopefully will get to the answers soon, but if you can share some pearls of wisdom then I am all ears. Also, don't know what to do about the injectors, they are a BIG ticket item and as you can see above, my wallet is still smoldering from the hole I made in it from the early Christmas shopping spree

[maarzz]

Any input on the above guys? 👆🏽