hesitation at full throttle

[alex_evo]

Hi guys
Got an Altezza rs200 (3s beams)

Im having a problem where if i full throttle there's a hesitation around 4-5k rpm, as if its being strangled at that point, then the power will come after that.

If i use around 60%-70% throttle it will rev cleanly up and down the rev range with no problems.

Gave it a service with new iridium plugs and genuine toyota oil filter and 5w30 castrol edge oil

I cleaned the MAF, reset ecu and cleaned the throttle body(without taking it off),ran fuel cleaner aswell, stock airbox with K&N panel filter and still no good,

After resetting the ecu (by removing battery) it doesn't idle properly it jumps from 1k -3k up and down for awhile, i switched the engine off then started it back up again and idle was fine so maybe leave it longer ?

No dash lights, everything is fine as long as its about 70% throttle or below

my previous altezza didn't do it before and seemed quicker

Any ideas ?

Thanks

[donato]

The fluctiation in the revs is normal for the first while the engine learns it's calibration from the sensors. It'll go back to normal after a bit.

[alex_evo]

should i leave it longer and drive it after resetting the ecu and wait for the revs to settle would that help ?

As i didn't really let it calibrate, i just switched the engine off after resetting the ecu

[donato]

Yes. Leave it on idle for about 15 minutes then take it for a 15 minute drive and it should be fine after that.

[alex_evo]

cool i will give that a go and see if that will help with the hesitation

[alex_evo]

ECU reset and still hesitation at full throttle, low revs everything is fine, but once you put the throttle down at around 4k-5k rpm it feels like something is strangling it

Any ideas ?

[jubo]

Hi!
I have the identic problem with my rs200. Only difference is that when I suddenly put my foot down from 0% throttle to 100% it hesitates for aprox 1 sec and then goes. The power comes on after the 5k rpm "strangling" in aprox 5.5k - 6k rpm.
I'm using 95 octane fuel and wondered that could 98 octane fix the problems if the car is picky for fuel.

I have already changed the sparkplugs, cleaned MAF and reset ecu. After ecu reset a new problem came up. Now when lightly accelerating the acceleration is uneven (could be the ecu still learning cause only driven 30kms after reset).
It would be nice to get solution for this.

Thanks

[Podgerr]

Have same type of issue have is200 3g also...have had a slight rattle coming from engine but its now accompanied by the same power loss/choking u describe but @ 3k rpm clean running before and after this rev range..have changed plugs, cleaned maf, cam belts plus ten and w/pump done, was running car on 91 for ages switched to 98 but issue remains..taking to see mechanic in the morning...will post back after that. Funny thing is I can sometimes drive and there is no issue at all, its now happening more frequently hence mechanic time, plus I'm out of ideas.

[jubo]

Found one solution on same problem
http://www.tezzaworld.com/viewtopic.php?t=9364

Thanks to those who helped.All sorted now.I cleaned the MAF sensor and replaced the original intake unit and its working like new again.I believe the cam cover breather was part to blame.All the oil mist from when I had in the blitz induction kit soaked the plugs and was causing premature ignition at that point.Thats what I believe.Lol.Any more ideas welcomed.

[jubo]

Got mine working again. Cleaned maf-sensor again more precisely, cleaned throttle body without removing it and checked the vvti solenoids.
Don't know where exactly the fault was but in one of the above- mentioned.