SCOSaltire

replaced the h-t leads and plugs last week.
car ran the same
Did a reset last night.
car is smooth this morning.
very slight signs of the hesitation.
went for a 30 miles drive
much smoother... but still some small signs of hesitation.
idles with lightly less hunting.

i suspect this will get worse with time again...

still to try:
new maf

or is it a feature?


[Edited by SCOSaltire - 7/7/2002 1:39:30 PM]

STi wanna Subaru

iTrader: (1)

.. what are the likely candidate for the cause when the engine is warm. Lambda, MAF, Leak in the intercooler pipes? I've picked these up from search. Although nothing really has establised as the exact cause from what I can tell.

I want to work through the main causes of the dreaded hesitation on my MY99 Uk Turbo. It has only started last Friday after 7500 miles of near faultless running

Jolly Green Monster 2

7500miles?? the service interval... has it just started after a service? or is it due one soon?

Just a though.. could be they messed with the timing at service or that your plugs are due to be changed at next service...

just guessing.

JGM

STi wanna Subaru

iTrader: (1)

it had intermediate service about 3 weeks ago and was fine after. Plugs are pretty new as well not a year old yet. I'm thinking MAF at the momment.

Can the dealers check the MAF is functioning correctly?

SCOSaltire

they can
but ....
i hope u have a good dealer
ive been to 2.. both said its fine
to be fair... its checked out ok on others too.
tho there was a failure in the history.. found by an independant... was reset then... no history since...

i am thinking that perhaps the problem with the maf might not be picked up via its data... sounds silly.. but might be true...
hmm

Uzi Lover

...I had the exact same problem with an MY99 until I took it to the dealer on Monday. It was becoming so annoying because it would only happen intermittently but would always seem to occur between 2000 and 3000 rpm's.

A new set of leads seems to have cured the hesitancy for the time being, until something else goes wrong.

STi wanna Subaru

iTrader: (1)

I thought it may be a lead breaking down. So difficult to check though without replacing them all. How much was a new set?

SCOSaltire

got a new set of leads too.. not solved it either..

Flat4-Chris

How severe is the hesitation you guys are talking about? I've been reading about it on other threads because my MY00 UK Turbo's just been for it's 30,000 service (spark plugs, fluids chaned, the lot), and it seems to have developed a slight hesitation just below 3000 rpm.

It's really slight, you can only really notice it on a smooth road otherwise it's disguised by the bumps. On a constant light throttle in third you feel the car momentarily hesitate, I wondered whether it was because it was just coming on/off boost at this rpm or whether it's the hesitation problem that I keep hearing about.

STi wanna Subaru

iTrader: (1)

Chris, that's it mate......hesitation! It's driving me mad! i suspect mine is slightly worse

Flat4-Chris

So, is it worth talking to the dealer to get them to look at (it's still under warranty so I don't want to upset them), or do they deny it exists and tell ppl that they're imagining it?

STi wanna Subaru

iTrader: (1)

I'm yet to take mine in as I've not had time as yet. Subaru are aware of it but how good they are at addressing the problem I will have to leave to somebody else to answer.

Do a search for Hesitation or Poor running, there a loads of threads on the subject, unfortunately none offer a definative answer.

Flat4-Chris

Cheers m8.

I'll search about a bit more, but as I've got some time next week I think I'll see if I can get the dealer to have a look. It definately started after the service so something they changed has kicked it off.

If they say anything useful I'll post it.

STi wanna Subaru

iTrader: (1)

Cheers mate, I hope they find the problem

SCOSaltire

i think mine started after the 30k service too....

DaveD

iTrader: (2)

Not sure if I'm suffering exactly the same problems as everyone else, but I changed my spark plugs a few weeks ago (and dp at virtually the same time).
After about a week the car started to develop hesitancy at around 2k - 3k rpm, and the idle also hunts slightly. Feels like the car is juddering slightly as you drive along at low revs.
I'll pull the plugs out over the w/e to see how they are burning, and let you guys know the results.

SCOSaltire

That would be good dave

I am trying an ecu rest tonight.. see what happens tomorrow

DaveD

iTrader: (2)

Ok,
checked the plugs today, and on the piston side all seems good. Plugs are a slightly blackened (sooty), but I would expect that's due to normal over-fuelling - ie, no cause for concern.
On the other end of the plug, I did notice that some of the tops where the plug connects to the coil pack (HT lead on more modern versions) was blackened. I suspected this could be dirt, but on inspecting the coil pack, found the contact to also be blackened, and slightly pitted. I've cleaned these areas up with some tissue and WD40 (the coil pack still aren't perfect).

Took the car out for a check run, and now seems to be a lot smoother . I'm not sure if this is only a temporary fix, but running at 30mph is now smooth, and the idle doesn't hunt (although there is still an occasional missed beat).

So it would seem that the symptoms seen above are probably HT-related in some way?
Hope this is of some help.

STi wanna Subaru

iTrader: (1)

Well seen as though mine started doing it after running fine for 8 months I wont accept it's a "feature".

I think I'm going to try a new MAF and see if that makes a difference.

SCOSaltire

yeah - i dont think its a feature either...
esp as it started for me about 9 months ago

i know that when its doing it.. its the timing being changed...

maf change and reset is a good idea.. i think...
gonna ask for one on monday

STi wanna Subaru

iTrader: (1)

SCOSaltire,

What is the spec of your car? Mines running a full de-cat and K&N panel. I'm going to put the paper filter back in and get it to a dealers to see if they'll change the MAF under warranty.

let me know how you get on

Cheers

Guy

SCOSaltire

mine is my99 uk turbo
PPP

going full decat within 3 months (warranty )

Flat4-Chris

Just had my 00 into the dealer today. They reckon they couldn't find anything wrong, maybe as is usual it behaved itself when they took it out?

They did show me a report from Subaru UK about hesitation problems between 2500-3000rpm. Subaru say its normal behavior and that it's the boost kicking in and going again because the driver is only just giving enough gas to keep up the pressure in the manifold up. Subaru try to call this "turbo lag" I guess to keep some punters happy...

Not entirely convinced by this, but as mines only a slight hesistation I'm going to see how it goes for now.

cheers all. Chris.

SCOSaltire

Chris
I saw the same information from subaru.
'Turbo lag'
wonder what that means..
woosh / stop / wooosh / stop / woosh / stop
happens on 1/3, 2/3 and WOT

but the funnist bit is how it started to get worse...
i can only assume that something happened for the car to start doing this.

my dealer, who is very good, seems to think i may end up chasing this forever.

I am gonna ask / try for the new maf sensor.
then see how the land lies.

SCOSaltire

interesting!
that was quote from MKC's thread:


[Edited by SCOSaltire - 7/10/2002 2:44:33 PM]

[Edited by SCOSaltire - 7/10/2002 3:38:40 PM]

STi wanna Subaru

iTrader: (1)

have you got a new MAF yet mate? I took mine out to have a look if I should try cleaning it but as I need the car at the mo I didn't want to bugger it so I left it alone.

SCOSaltire

ive had my maf cleaned.
it looked quite shiny

havent phoned the dealer yet... will do

STi wanna Subaru

iTrader: (1)

did it make any difference? Mine looked like quite dull.......like the metal was slightly oxidised. maybe i'm clutching at straws!

SCOSaltire

it did make a difference...
but.. did an ecu reset at the same time...
i am thinking that the reset was the cause of most the difference in performance

it might not be the maf, of course

SCOSaltire

got the maf ordered
should have it by monday
ill let u know how it goes