flat4_ire

hey guys,
ive just got my first impreza fresh from japan last week (98 V4 Type R) had it serviced and checked over and the mechanic said it was in great cond etc, no damage etc etc..its running like a dream but sometimes when im sittin there in neutral the car mite drop and then jump between say 400rpm and 800rpm..then it'l just settle to 600rpm or so. this sound weird or what? he hadnt got the plugs last week but im gettin them changed this week, u tink that mite be it? o is it just finding itself with fuel or what?

flat4_ire

nobody? jaysus whats the story with yis

New_scooby_04

iTrader: (4)

Dare I suggest the M word? Uneven idle can be an indication of a falling MAF. Get it checked ASAP. Dodgy MAF can kill an engine! Could be a number of other things though.

You are running it on SUL (preferably Optimax) and octane booster aren't you?

NS04

corradoboy

Agree with NS04, MAF Especially if you have noticed a flat spot at around 4k revs too. Either get it to someone with diagnostic capabilities or do an ECU reset yourself. I don't fully know how to do it as I've never had a classic but it involves joining some connectors under the steering binnacle together. Once reset the ECU will be able to spot a failing MAF, but as it progressively fails the ECU compensates for it and thus it's never very apparent. They are a known weak component on 98-00 cars, budget around £90 for a new one (beware someone doesn't sell you it with the housing as they'll want about £200+ for it ). Many people replace them annually on cars from those years.

stewfo

iTrader: (2)

I am also having a similar problem, got the car back from the garage after getting brakes fixed and car is ideling at 800rpm but dips now and then. Also when car is cold it feels like it is has surges that comes in waves below 3000rpm. This all started after i had a disagreement with the garage over the brake problem.

pslewis

FFS

Who makes the MAF? Cos' I am going to buy £50,000 worth of shares!!!

Good God they must be selling faster than Live8 Tickets!!

Pete

New_scooby_04

iTrader: (4)

Uncle Pete's here!! Weren't you concerened about a poss MAF failure on your car a while back Pete...when considering the pros and cons of the warranty?

BTW its now MAF 8 tickets!! Get with the times!

flat4_ire

what the **** is maf?? a sensor i take it? no flats spots at all, runs like a dream, this only happens sometimes,could it be
timing?

corradoboy

Mass Air Flow, measures amount of air coming into induction. Corresponds to AFR (Air Fuel Ratio) sensor to determine correct fuelling for relevant boost levels. TBH all these sensors are a PIA You also have a lambda and an O2 sensor on the exhaust side. All of them can cause trouble, but the MAF causes the most serious as it leads to the engine running lean and that can lead to meltdown

As I said earlier, you can do an ECU reset yourself, and afterwards if there is anything wrong you will be given an error code by the CEL (Check Engine Light) flashing out a 2 number code. A quick Google should find you a reference to the error codes, but it's easier to let someone with diagnostics to plug in and tell you what's wrong immediately.

Butty

iTrader: (2)

I'd go for the plugs. Did they even get removed & cleaned up during the service?
The 97/98 MAF is a more robust type but costs IRO £250 to swap as it doesn't come apart.
Don't buy the MAF until you've got some new plugs in. If you can't wait then pull out the old ones, give them a clean and regap to 0.7mm.
Its the cheaper option to rule out before spending some money.

Nick

New_scooby_04

iTrader: (4)

Yep, sounds like a good idea, but I'd also suggest driving the car off boost untill the MAF can be ruled out!

Stilll a question over what petrol you're using and if you're using OB?

NS04

flat4_ire

95 unleaded cos its all we have in this kip of a country, and millers cvl turbo octane booster, im gettin the plugs done soon so maybe that will sort it, the mechanic going to check her out this week too, car is running perfectly apart from this,no flat spots,starts first thing and ticks over fine,,only sometimes when engine is warm it happens, up and down 2/3 times then levels out at 600rpm ok

BLACK V5

Import sti & 95 ron. O my god, hope you have deep pockets.

flat4_ire

what would u know lad?? a friend of mine has a 95 import wrx and hes been using 95ron without booster too! and it has 194,000 klms and its runnin fine!
we aint got anything else here, so if thats all u can say then save ur opinion ok?
3 of my friends have import scoobs and all run on 95 and booster and never any probs..anyone else anything intelligent to say?

New_scooby_04

iTrader: (4)

If you're using the appropriate quantity of OB then you should be ok. However, V5's comments on running an import on lower grade fuel (without OB) are sound; it's a bad idea! I don't think he was having a go.

Here's an "intelligent" comment from David at API

Running on wrong fuel on an import car. Detonation.

David APi Engines / APi Impreza
www.apiengines.com

The thread is here

http://bbs.scoobynet.co.uk/showthrea...ngine+failures

You could always get the car re-mapped for the available fuel.

flat4_ire

97 sul was available here in ireland until one month ago,stopped stocking it then, now 95 is all we can get, its stupid as **** but thats the way it is, u suggest everyone in ireland stay away from jap performance cars??im using millers cvl turbo OB which was recommended by andy f so what else can i do ya i do ya know? my apexi power fc is here in 2 wks,andy f is comin to map it..i cant do anymore than that , car is mint anyway, hope to keep it that way..

New_scooby_04

iTrader: (4)

I'm not criticising you mate, you are indeed doing all you can! If you're using OB you should be alright, & if you're having the car remapped for the fuel that is available then that should ensure that you don't run into any probs. You've also chosen one of the most respected and well liked mappers on here, so good on ya for doing your homework!!

NS04

flat4_ire

stupid country with their 95 unleaded, wont hold me back from having my type r baby!! il do me best anyway

Jasper1609

I have noticed my MY99 RB5 has an uneven tickover but it is intermittent
seemed to start doing it after last service oil change etc used all Subaru parts
the only thing i changed from standard was the plugs I used NGK PFR7B's ,Could this have had am affect

flat4_ire

maybe lad yeah im not sure though, gettin my plugs changed next week so we'l find out the story then

shanewrx/sti

Hi mate my car idles funny in the morrnig when cold have you got any ideas what this could be? thanks shane