Hi, still new to the site. I've got a classic Impreza wagon v reg.

its got an irritating hesitation nearly all the time, but noticibly worse just cruising/commuting. I've changed the air flow meter and oxygen sensor. But it's still happening. Another problem is it's only boosting at 0.4bar and isn't very Impreza like. Any help would be appreciated!

did you use a gen maf ? 

 

tried usual plugs and leads?

 

boost leak?

As above. Not the best time of year but go round and check all your vac and intercooler hoses.  Make sure turbo hose is also tight. 

Any cel? 

5 hours ago, matt said:

did you use a gen maf ? 

 

tried usual plugs and leads?

 

boost leak?

Used a genuine maf yes. Haven't tried plugs and leads yet, I noticed when I unplugged the oxygen sensor it ran almost perfectly so presumed it was the sensor but no better. There were 2 codes, 24 and 32. 32 would more than likely be from me unplugging the oxy sensor and 24 said idle air control valve? ive erased the codes and going to run it and check again. Thanks guys!

I thought if you had a boost leak you would hear it? Wooshing out?

Not always but if it's the inlet you can hear it a little trying suck air in 

I've done numerous smoke tests on the engine but not luck in finding any leaks.

Smoke tests aren't worth it mate don't show it ifcnot under load 

Visual checks only then.☹️

Yeah the inlet is the most problematic !! Getting at it / off is a pig