Lose power as engine heats up

[studio54]

Thread revival !

Same here, since having my car (n54 135i) i always noticed this behaviour and wonder if it's normal or not ?

Definitely not a 29.2 issue cause it's MHD tuned so it get rid of this problem.

During warming period without WOTing or red lining it (under 3000rpms), the low end torque seems to have more power, more responsiveness and quicker spool than when warmep up.... DTC activates, eventully tyres spins while barely pressing the throttle pedal. Once it's warmed, it just feels laggier. The power is there, but in mid and high end. This initial low rpm peppy feeling is not there anymore.

Are we in the same boat, every n54 does that? or is there any issue ?

Any possibility it could be a bad (partially clogged?) mid catalytic converter? I know these stuff starts to really work when it's warmed.

If it's related to air temp in the combustion chamber, does a walnut blasting helps? (never done it yet, but plan to do it)

[Unai]

Originally Posted by sonicgrounds

Is it my car or is this the way the turbo engines work, because I'm coming from an e39 M5 and this is beginning to bother me. The car pulls like a train until the engine reaches it's full operating temp and as it gets there the power goes down (not by a lot but noticable amount), or rather the peak TQ rpm goes up, meaning it only starts to pull at 4-5k rmp as oppsed to 2-3k rmp. Is this normal?

Hey, did you solve the issue? I have the same problem with a 335i. When the engine is hot the turbo doesn't spool at lower rpm and I end up getting a 30ff - low boost pressure error.

[szzimo53]

Originally Posted by studio54

Thread revival !

Same here, since having my car (n54 135i) i always noticed this behaviour and wonder if it's normal or not ?

Definitely not a 29.2 issue cause it's MHD tuned so it get rid of this problem.

During warming period without WOTing or red lining it (under 3000rpms), the low end torque seems to have more power, more responsiveness and quicker spool than when warmep up.... DTC activates, eventully tyres spins while barely pressing the throttle pedal. Once it's warmed, it just feels laggier. The power is there, but in mid and high end. This initial low rpm peppy feeling is not there anymore.

Are we in the same boat, every n54 does that? or is there any issue ?

Any possibility it could be a bad (partially clogged?) mid catalytic converter? I know these stuff starts to really work when it's warmed.

If it's related to air temp in the combustion chamber, does a walnut blasting helps? (never done it yet, but plan to do it)

Hi,

I have the same problem, did you solve it? I feel the power when the engine is cold, throttle aggresive , wheels spin. After warmup the car suddenly feel slow, and less responsive. I have everything car is Stage 3.

Thanks

[ShocknAwe]

Your fuel and intake temps are heating up. Worse in summer.

Easy fix is adding 2 gallons of E85 to the tank. Stops predetonation and stabilizes your ignition system under boost and spool conditions.

Can also add things like phenolic spacers to the fuel rails and a better FMIC, but trust me the problem still exists.

[szzimo53]

Originally Posted by ShocknAwe

Your fuel and intake temps are heating up. Worse in summer.

Easy fix is adding 2 gallons of E85 to the tank. Stops predetonation and stabilizes your ignition system under boost and spool conditions.

Can also add things like phenolic spacers to the fuel rails and a better FMIC, but trust me the problem still exists.

I still beleive this is not temperature problem. Have too much difference regarding power amd response. When car cold after start up, i do some little pull and i almost cant hold the car on the road in 1st 2nd 3rd gear, superfast response and powerfull. After warmup like 20-30 min later , I feel to much decrease on sensibility and throttle response, like a hidden magic switch button slowdown everything.

[ShocknAwe]

Log the difference. Make sure you aren't in an alt fueling mode or failsafe timing table map

There are lots of safety maps you could be getting kicked onto.