DCT Lag/Engine Overheating

[cam135is]

For two months the dealer could not figure out what was going on with my 135iS. Between 1st to 2nd and 2nd to 3rd, after shifting there would be a delay and the engine would be in a limp mode for about 2 seconds then go to the next gear. The dealer claimed it needed a computer update (which they could not do). I was in traffic and the message came up saying engine over heating. I take to the dealer and they replace the cooling fan, stating it was not working. While doing this the tech tore a coolant hose(whom after wrapped another hose around it and clamped it because he could not figure out what the part was). Two days later the same issues happen again. I take it to a Euro only specialty shop and in 30 mins diagnosed and ordered the parts. The cooling fan relay was not working, which caused the computer to tell the engine to protect itself, inducing the bad shifts. No computer update was needed. For the coolant hose, it was not listed in the diagrams or catalogs. BMW USA could not identify either. After about an hour the owner, figured it out. It was the coolant hose for the auxiliary PPK cooling system that came on the 135iS model. Long story short, if you're having the bad shifts, check the cooling system.

[dtla1]

Surprised to hear they would let a dealer tech do such a BS fix to wrap another house around a punctured coolant hose and clamp it down. That's a straight up side of the road fix right there.

Any additional info on that fan relay? Part number, location, etc?

[zx10guy]

Not sure why the shops were having difficulty in figuring out part numbers. Here's a thread I created when I bought the PPK2 to install into my car:

https://www.1addicts.com/forums/show...highlight=ppk2

The thread has pictures of the parts and a scanned PDF doc of the parts list with part numbers.

The upgraded fan relay is mounted on a metal bracket that is mounted in the area just behind the driver's side headlight.

[dtla1]

Originally Posted by zx10guy

Not sure why the shops were having difficulty in figuring out part numbers. Here's a thread I created when I bought the PPK2 to install into my car:

https://www.1addicts.com/forums/show...highlight=ppk2

The thread has pictures of the parts and a scanned PDF doc of the parts list with part numbers.

The upgraded fan relay is mounted on a metal bracket that is mounted in the area just behind the driver's side headlight.

Thanks for the note about the relay, I'll have to dig deeper to see where the non PPK one would be, if applicable.

So I went to your original thread, and in the parts pdf you posted, I noticed that the spark plugs listed (0037244) are for an N54 originally. Do you know if that was an error (maybe they sent you the kit for an N54) or if the N54 plugs actually do work (and maybe better on mildly tuned cars) on an N55?

[zx10guy]

Originally Posted by dtla1

Thanks for the note about the relay, I'll have to dig deeper to see where the non PPK one would be, if applicable.

So I went to your original thread, and in the parts pdf you posted, I noticed that the spark plugs listed (0037244) are for an N54 originally. Do you know if that was an error (maybe they sent you the kit for an N54) or if the N54 plugs actually do work (and maybe better on mildly tuned cars) on an N55?

I had a discussion about this a while ago on the forum. The N54 plugs were indeed sent with the kit. They were installed in the engine during the PPK2 installation. Subsequently, the dealer replaced the plugs with the N55 spec ones. I don't recall the content of the discussions we had but I'm just going with N55 spec plugs now. Sort of don't have a say in it as I still have the extended factory maintenance plan and the dealer is going to put what they feel is correct in the engine anyways.

[dtla1]

Originally Posted by zx10guy

I had a discussion about this a while ago on the forum. The N54 plugs were indeed sent with the kit. They were installed in the engine during the PPK2 installation. Subsequently, the dealer replaced the plugs with the N55 spec ones. I don't recall the content of the discussions we had but I'm just going with N55 spec plugs now. Sort of don't have a say in it as I still have the extended factory maintenance plan and the dealer is going to put what they feel is correct in the engine anyways.

I must have missed that discussion on here. For a second there I thought this might be a big discovery! haha

[zx10guy]

Originally Posted by dtla1

I must have missed that discussion on here. For a second there I thought this might be a big discovery! haha

From what I recall, it was buried in another thread so it wouldn't have been obvious. I'll see if I remember enough to find the thread.

[Esteban]

Originally Posted by zx10guy

From what I recall, it was buried in another thread so it wouldn't have been obvious. I'll see if I remember enough to find the thread.

PPK1 here (with Dinan S2), and I remember reading about this when it was time for me to get new plugs. It made me wonder as well why your PPK2 came with N54 plugs. I went with N55 plugs (BMW 12-12-0-037-582) again and my car continues to run strong.

PS - I saw above where you said you are now using N55 plugs.

[MightyMouseTech]

Originally Posted by dtla1

Thanks for the note about the relay, I'll have to dig deeper to see where the non PPK one would be, if applicable.

So I went to your original thread, and in the parts pdf you posted, I noticed that the spark plugs listed (0037244) are for an N54 originally. Do you know if that was an error (maybe they sent you the kit for an N54) or if the N54 plugs actually do work (and maybe better on mildly tuned cars) on an N55?

Do NOT install the N54 plugs into an N55. Terrible misfires. This is coming from experience after installing the plugs that came with my PPK2 kit. Only use the standard N55 plugs. It is the same kit N54 or N55, and the plugs did not get updated.

[dtla1]

Originally Posted by MightyMouseTech

Do NOT install the N54 plugs into an N55. Terrible misfires. This is coming from experience after installing the plugs that came with my PPK2 kit. Only use the standard N55 plugs. It is the same kit N54 or N55, and the plugs did not get updated.

Thanks for the first hand account and clarification sir.

[zx10guy]

Not to dispute MightyMouseTech's advice, but when I had the N54 plugs in my car, I didn't have any issues. Granted it might have been masked by the DCT driveability issues I had during the time I had the N54 plugs installed.