Got a hesitation problem on my 03 WRX turbo.. it's there slightly most of time, when changing gear, but mostly noticeable when driving spiritedly. If I give it some in 1st and change quickly into 2nd there's quite a bad hesitation before it picks up again, it's still there but not as bad from 3rd to 4th. Earlier I decided to pull the plugs out and check them, so first thing I did was take off the air filter, a Pipercross cone type thing, with the MAF sensor attached. I then thought I'll just see what happens without the filter on, started it up and it ran fine, so I gave it a blast round the block, and it drove exactly the same as before. So no difference with the MAF on or off, does this mean the MAF is knackered? Is it worth trying a cleaner on it? If it is knackered how much am I looking at for a replacement.

Sorry for the long winded post, hope someone can help a total scoob n00b.


BTW.. after realising removing the MAF didn't make a difference, and it was getting a bit late anyway, I didn't bother to check the plugs yet.

 

Anyone please?

 

Update.. have since checked, and regapped to 6.5, the plugs, the previous owner said they'd recently been changed and they did look new. The problem is still there, and I've since noticed it's not just at speed, it's there all the time, but mainly if you try to change gear quickly. If I drive carefully I can get the car to drive fine, but if I try to just drive the car without easing the clutch out there is a very apparent hesitation/miss when changing gear, could the maf cause this?

 

i have a 02 wrx and it also hesates. Mine does it when you change from 1st to 2nd gear slowly ( the revs a low) and it will like jerk forward. It also does it when doing about 2.5rpm in third and accelerate.

Ive been told to check plugs and coilpacks

 

Yeah I read that when I did a search for similar problems, plugs are fine, haven't checked the coilpacks yet as it does seem there's a problem with the maf, considering it makes no difference to how it runs if I take it off.

 

Have you had the car mapped to run with the cone filter?
If not try fitting the standard air intake and see if that makes any difference.
For some reason subarus dont like cone filters.

 

The filter was on it when I got it, and unfortunately it didn't come with the original set up. It has been chipped and mapped at some point, don't know if this was before the filter or after.

 

Just had a look through the receipts and the filter was bought in 2005, shortly before the chip too, so can't see it being that. Thanks for the input though, everything I can eliminate is a bonus.

 

I would guess that if the car runs the same with or without the MAF connected then its faulty - you can check the fault codes to be sure though

 

The only time it throws up a fault code is if I disconnect/reconnect it, another thing that confuses me.