What's this hesitation problem? (MY94 GF8)

[swamp]

Hey guys

 

When cold, sometimes my car will start to hesitate/lag/jitter back and forth in second gear/third gear. Usually the problems solved by either just driving at 40km/h (it comes on usually at 50km/h) or changing up a gear and revving. 

 

If it helps I think my AFM is clogged up with gunk from the oiled filter (will get new non-oiled filter installed into the fender soon, a long with cleaning the AFM and throttle body), and I need to get codes read from supercheap. 

 

I think it could be either AFM or spark plugs/coil packs? I have watched boost gauge stay on and it doesn't show any loss in boost. 

 

I've read online that it could be a BHG... but how could a blown headgasket cause a hesitation problem? I don't hear any backfiring or misses.

[GC8E2DD]

I would definitely start with the AFM.

[THUNDA]

1st things first - Definitely clean your AFM and loose the oily filter imo.

Then after that give your Idle control valve a good clean out.

Id say coil packs are fine because they commonly break down under boost, so when its hot and your boost is strong - then the coil packs are doing their jobs  

Id also say its highly unlikely its you head gaskets, probably the last thing id check on a very long list  

[swamp]

19 minutes ago, THUNDA said:

1st things first - Definitely clean your AFM and loose the oily filter imo.

Then after that give your Idle control valve a good clean out.

Id say coil packs are fine because they commonly break down under boost, so when its hot and your boost is strong - then the coil packs are doing their jobs  

Id also say its highly unlikely its you head gaskets, probably the last thing id check on a very long list  

sweet! Have we got an article on cleaning the idle control valve on the forums? 

 

The oily filter will go, I will run it over and then drag it down town like a Subie driving cowboy