Big Hesitation at 4K revs... 02 WRX.... any ideas ?
 

I've noticed over the last week or so that at 4K revs, the car seems to hesitate. It pulls hard to 4, seems to struggle to 5, and then picks up again.

Does anyone have any ideas ? Passengers have said they can't feel anything, so it's not a major drop in performance, but I know it's not right.

It's an 02 wrx, always run on super unleaded

Cheers
Darren

Have you got a boost gauge? is there any drop in boost pressure at this point?

I do have a boost gauge on the secs monitor. I'm 95% sure there is no boost drop. I'll check later, but I'm pretty sure no.

Cheers
D

Mine was lifting off around that area as well, I have an STi though.


What fuel have you put in it. I think mine was caused by normal unleaded being put in it.

Also, I found that by blasting it over and over it seemed to clear, it was only the first few blasts.

Symptoms of MAF failure or overboost, if your boost is constant suggest swapping your MAF out for another.

MAF?

Mine was like that with faulty O2 sensor.

The boost pressure didn't seem to drop although last night it seemed very reduced. My passenger keeps saying he can't feel a thing, and it was very minimal last night... was about 2 degrees though and running well in general. I'll keep an eye on it !

The airflow sensor in the intake pipe. Mass Air Flow. To test, unplug it when the engine is idling, if the car dies, it's good, if the engine chokes and then picks up it may be on the way out, if there's no change to the idle, it's dead. Do a search of 'MAF failure' plenty of info on here.

That is exactly the same as mine!

I took it to the garage and they plugged in the monitoring machine whilst the guy booted the motor I watched it on my lap. I was getting up to 10 something on the boost, which he said was normal.

Perhaps a MAF unplugging needs to be done.

I have searched, can someone tell me exactly where this plug is on an STI '03 plate car?

Exactly the same thing on my MY99. MAF sensor failure was the culprit. :)

Same issue for my MY99, same solution!

It's just on the engine side of the airfilter housing in the centre of the inlet pipe, can't miss it. No pics, sorry.

Don't know whether this will help, but the arrow is pointing to the General area; the sensor is mounted on the side of the tubular housing, AFAIK

http://www.wallpaperinstaller.com/scooby/intake3.jpg

Thanks for the info... I will give it a try later........

Darren

Cant see an image buddy? Just the usual red x in a box.

That's bizarre.... I can see it and I have quite a strict firewall at my place.... Can't think why you don't see it. :confused:

What about this one? It's on a classic this time, but they're in the same place.

http://stefanostadal.homedns.org/ima...eng/itg_01.jpg

Sorry for the Delay.... I finally got around to pulling the sensor, as I had some daylight today.... and it stalled straight away. I guess this means it isn't that. However.. I now have the engine light on permanently. Any ideas ?

I turned the engine off and left it a few seconds, but even when I restarted it, the engine light now stays on...... is this something I need to get subaru to rectify ?

I have a secs monitor, adn it's showing no errors/events at all

Cheers
Darren