Aging 135i's. Worsening Fuel Econ? Power Down?

[BiscottiGelato]

Is it typical to have power coming down and fuel economy worsening? I do track my car. I have been doing oil change about every 8000km. Been on Mobil 1. After the latest change, it feels as if my car dropped 1 full L/100km in fuel economy. Never dynoed my car so not too sure about whether any acceleration decrease either...

Any common issues that I should look out for as my car ages? At 77,000km right now. Maybe clutch is starting to go? Please advise on area I should pay attn to. Thanks!

[gregthegr8]

Originally Posted by BiscottiGelato

Is it typical to have power coming down and fuel economy worsening? I do track my car. I have been doing oil change about every 8000km. Been on Mobil 1. After the latest change, it feels as if my car dropped 1 full L/100km in fuel economy. Never dynoed my car so not too sure about whether any acceleration decrease either...

Any common issues that I should look out for as my car ages? At 77,000km right now. Maybe clutch is starting to go? Please advise on area I should pay attn to. Thanks!

You may want to get your engine walnut blasted as that might solve much of the engine woes you may be experiencing. I'd start there, as that cleanup may get a ton of gunk out of your engine and have it perform back to normal and at a more efficient level as well.

[BiscottiGelato]

So everybody else have awesome power and fuel econ all the way up to 100k miles?

[Cheeze1]

Originally Posted by BiscottiGelato

So everybody else have awesome power and fuel econ all the way up to 100k miles?

Did you see the post above yours? Have you ever had your engine walnut blasted or at least checked for carbon fouling?

[gregthegr8]

Originally Posted by phil97m3blue

Did you see the post above yours? Have you ever had your engine walnut blasted or at least checked for carbon fouling?

Hey, I tried. Plus, there aren't too many 135s past the 100k mile mark.

[Dackelone]

Old Spark plugs? Injectors?

To me(and to others) this sounds like a classic case of carbon buildup.

What "other" problems does your car have that your gonna tell us about? Rough idle? Surging while cruising at a constant throttle position. ???

[P90Puma]

I am double your KM and the car is fine, get it walnut blasted like the others have said.

[ShocknAwe]

Originally Posted by gregthegr8

You may want to get your engine walnut blasted as that might solve much of the engine woes you may be experiencing. I'd start there, as that cleanup may get a ton of gunk out of your engine and have it perform back to normal and at a more efficient level as well.

This is where I would start. At least have it scoped.

[MZWIE]

I'm at 90k miles w/o walnuts. Still going strong.

[JDelphiki]

I'm at 76k miles and had the carbon build up taken care of twice so far, each time the car feels like it breathes better, especially on the top end. My MPG is around 19 for city driving and if I make road trips I can get 25MPG fairly easy.

No performance mods, I do have Apex Arc 8's on MPSS tires and the ducktail spoiler with carbon rear diffuser.

[BiscottiGelato]

Hmm. I don't really feel the engine having any other issues. Maybe the clutch getting a little weak. Maybe a clutch change in order soon.

I'll look into Carbon build-up and Walnut Blasting. Thanks!