riggy10

Can anyone help, have owned a '99 impreza turbo for the last 5 months and think i may have a problem developing. When i get to around 4,000 rpm and accelerating, i tend to get a bit of hesitance, almost seems like she's holding back for 2 or 3 secs and then accelerates fine. Tends to do this through gentle and hard acceleration. Didnt have this problem when i first bought the car. As i only drive the car locally and never really have the chance to 'boot' it due to wife and kids on board and to be honest never really go over 3,500 revs, is it poss carbon build up or a sensor fault. I have read that the ecu tends to set itself according to driving style. Anyone have any idea's ???

aceman_uk

Riggy,

I had exactly the same problem and had my cars electronics checked by several reputable garages. Could not fault any electronics and even told that car was mint ... BUT Still had issue with hesitation at 3-4k rpm when accelerating.

Decided to go to power engineering and told them what issue was and they put the car on their rollers.

Cant remember the engineers name but he was very meticulous and advised it was my clutch slipping and he explained it too....

Had the clutch replaced with an organic exedy and behold my pride n joy is back to its best...

So based on the above fella, I would have it checked too by having it put on rolling road.

I always fear rolling roads coz the car has to be thrashed, but if it is a slipping clutch then they wont ...

Just my tuppence...Hope it helps...

Aceman

p.s. guys at POWER ENGINEERING VERY professional and fantastic at what they do. Just my experience.

riggy10

thanks for that, but wouldnt i have clutch slip at lower or higher revs, and clutch pedal bites approx half way up?, to be honest, almost seems like a little fuel starvation in this rev range

Deano_P1

Boost hesitation can be solved by cleaning out the boost solenoid. Give it a try

riggy10

thanks deano, next question and may sound a bit stupid, where do i find the boost sensor as i have no manuals yet. Is it gonna be a case of squirting a bit of brake cleaner through or stripping out and cleaning, thanks

bob r

iTrader: (46)

This sounds like when I drove mine with the Maf sensor disconnected- DOH!
which may mean yours is goofed. If you are a full member you will be able to search for maf related threads.

riggy10

Cheers Bob, gonna give the boost sensor a go first, sounds like this is going to be a case of deduction. Know a pretty good Scooby garage near to where i work, so gonna try the easy stuff first and if push comes to shove, will go and see what they can do, just trying to get some idea's on what could be causing the fault and if i can sort them myself, its gonna be a cheaper option, but thanks once again m8.

Deano_P1

To clean the boost solenoid yes it will be a case of squirting in some brake cleaner into the hoses

dave247

mine is a my99 and im having exactly the same problem, tried cleaing the boost solenoidand that never worked, it wasnt the MAF sensor either. i am waiting for new leads and spark plugs to be delivered as its the only other thing i can thnk of

riggy10

Dave, thanks for that, have new ht leads fitted, but not plugs, could be a possibility i reckon

matttp1

iTrader: (2)

Just had an airflow meter fitted originally thought it was coil pack but it was airflow meter. With mine it was ok under hard acceleration but felt like it was misfiring replaced plugs as well. Soon as meter done it was like a new car

exvaux

iTrader: (1)

airflow meter?do you mean the maf sensor or the whole assembly

matttp1

iTrader: (2)

not sure gen subaru bit cost about £117 if that sheds any light

matttp1

iTrader: (2)

Just looked on the garage receipt and just says air flow meter

riggy10

isnt it typical, have just been out with family, no hesitation at all, accelerates fine through the rev range, yet for the last couple of days, she's been holding back, theres a gremlin in there somewhere

dave247

when i tested my air flow meter it seemed fine, car cut out soon as i unplugged it and my ecu test code showed nothing

chocolate_o_brian

iTrader: (22)

can i ask on this thread, where about the boost solenoid is on a uk my99 turbo? was gonna clean it out with some brake cleaner too, now ive had both the maf and lambda sensors changed. just to be safe... but not sure on whereabouts

jac2000

I have the same problem withmy 99 UK Wagon. Tends to happen more when accelarating hard, but not all the time so I havent done anything about it.
MAF is apparently weak on this year of car, but as above I dont know where it is or if it is the same as an air flow meter or how much they are! But let me know how you get on as it would be good to know what to do about this seemingly common fault on 99 cars.

exvaux

iTrader: (1)

drivers side suspension turrett theres a load of parts with pipes and stuff thats the boost pack but i have no idea what one is the boost solenoid

dave247

it has a blue clip on it, well it has on mine anyway. hope this helps lol

darren-h

my 99 is doing exactly the same changed the maf sensor,plugs,cleaned all pipes,checked for leaks etc but still no change,subaru mechanic narrowed it to the ecu apparantly theyed changed a few for the later ecu.hopefully getting my car mapped so i think tha should get rid of it.

dave247

would resetting the ECU work

riggy10

found the problem at last (hopefully). Thanks all you guys for the pointers, had a damn good look around the engine bay, checked everything i could see, found that a pipe had come away from the inlet pipe between the air filter box and inlet, noticed that there was a small elbow going up into the inlet pipe from underneath, this pipe had split on the elbow and was literally hanging a few mil adrift. This pipe came from the inlet trunking and goes forward to the drivers side front of the engine bay into a cylinder type housing with 3 pipes coming from the top. Cut away the split section of the pipe and refitted to the elbow, warmed engine up and took for a short 'blast', hey presto all is fine at present. Makes me wonder if this pipe was losing air slowly until if finally gave way and came adrift. Lets see how things go over the next few days and see if this really has resolved the fault.

Alan MaC

Well done Riggy.

Alan MaC

riggy10

Thanks Alan, hopefully cured problem
regards
Andy