au i6 a bit sluggish after long drive??

[HULK_I6T]

Took my au to ulludulla and back from western sydney.. about 270km and 3 hours trip each way.

car was fine on the trip, smooth etc.. but towards the end of the trip I started giving her some hard acceleration.. it just seemed sluggish.. bear in mind it had just been on freeway doing 110km/h most of the time for 3 hours.. it was uphill a fair amount of the way under load. Car had between 3 quarters petrol to full most of the way.

any reasons why car would feel pretty sluggish?? Even seemed to change up earlier than usual. Seemed to want to hold onto higher gears??

No odd symtoms like missing or surging or anything. just felt like its lacking power like it was a boiling hot day or like im driving uphill all the time.

Could it just be a bad case of heatsoak? Car didnt show it was hot or anything?

Im thinking just heatsoak and nothing can do to fix. Ill see how she goes after cooled down.

any theories?

[Bushbasher]

Sluggish like that sounds like a flow problem to me. Have a check of your cat and exhaust to make sure it's not collapsing or blocking up. I had a centre muffler broke up inside and caused symptoms like you described, also have had a collapsed cat that caused the same symptoms too. Either that or your air filter is blocking up. Did you drive through a dust cloud or bug swarm by any chance?

[HULK_I6T]

Ill try her around the block with no air filter see it it makes a difference

both cat and exhaust are almost new under 5000km for both

[Maka]

Is that jumping on it when cruising at 80 or 90 or jumping on it at low speed, mine seems to take off in second from a stop/ low speed a lot when driving sanely. Old coolant in it at the moment?

cheers, Maka

[HULK_I6T]

Originally Posted by Maka

Is that jumping on it when cruising at 80 or 90 or jumping on it at low speed, mine seems to take off in second from a stop/ low speed a lot when driving sanely. Old coolant in it at the moment?

cheers, Maka

No moreso off the line and heavy throttle.. Just felt like it was going uphill.. Slower than usual to rev out etc. like I was towing something or air cons on etc.

Coolant temp showed it was cool, no miss or surge.. Just felt like a really hot day when hot air is on intake and they get sluggish.

I'm about to take her out now for a spin. Been cooling down after the drive all afternoon.

Just feels a bit off the pace.. Not that it's not going but a good 10-20% Down on grunt over the way it usually goes..

Like it was towing something.

I recently put a thicker oil in the diff.. Could it get real thick when hot making it drag more?

[Maka]

No, the thick oil in the diff wont affect power delivery. What brand coilpack? Some of the cheaper brands are known to crap out soon after installation.

[HULK_I6T]

Originally Posted by Maka

No, the thick oil in the diff wont affect power delivery. What brand coilpack? Some of the cheaper brands are known to crap out soon after installation.

I drove it last night.. Seemed fine to me after all afternoon to cool down?????

0-100 in 8.1 secs according to my video timed runs. I took same video 3000km ago and it seems pretty much same..

But after my long drive yesterday, it was definitely lethargic feeling

Maybe intake manifold heat soaked? Or fuel heated up? Exhaust and cat really hot? Gearbox oil hot?

[HULK_I6T]

I took air intake off today and noticed the bracket holding the throttle cable and other cable lose..

I tightened up.. Car feels more responsive now?? Maybe throttle wasn't fully opening up?

Is the other cable a kick down cable for transmission or is it cruise control?

[Bushbasher]

cruise

[Maka]

Adjusting it (throttle cable) will help if the cable is stretched may feel a little harder to push down though losing a bit of sensitivity / feel.

cheers, Maka

[HULK_I6T]

did some 0-100km/.h sprints.. car looks to be going 7.8 secs with a quarter fuel

only mods cat back 2.5 inch and air filter + tickford snorkel.