N1CK

I borrowed my brothers 2000/w classic saloon to go away on the weekend as my wagon is up for sale and i dont want to pile on any more miles. I noticed that his car sort of surges/pulses as if its coming onto bost in stages

he said he'd noticed it before but got used to it so he'd not looked into it what could the problem be? the cars been really well looked after and other than this fault it drives really well could it be the mass air flow meter playing up?

Thanks in advance
Nick

fatboy_coach

iTrader: (1)

I had this on my car (same year and model), it took replacing the MAF, Lambda, and then plugs and leads to sort it (in that order, over a couple of months) however it still does it when it's cold, first thing in a morning!

Hope this helps, although on reflection probably not!

Ian

N1CK

i never thought of plugs and leads thats a good point i'll get him to check that, basically when your on the accelerator lightly then you slowly increase the revv's you can feel the car surging its really weird, is this the same as what you had?

Oh an i noticed he's got a slight blow on the exhaust up front, could this cause any probs?

JamesyWRX320bhp

iTrader: (2)

mine is doing EXACTLY that at the moment, 1995 wrx. i have changed the plugs, c/packs and have just ordered a new MAF! fu(king nightmare!

good luck, let me know if u sort it as i need to sort mine!!

N1CK

so it wasnt the plugs or leads? i think it must be something to do with the MAF, i cant really see what else would cause it, its only ever filled with high octane fuel so its not to do with the quality of fuel....could be something fuel system related though

JamesyWRX320bhp

iTrader: (2)

i've been told it must be the MAF - i just hope it is as its getting right on my **** now!! its only when u slightly touch the accelorator!!

Tidgy

get it checked out, it might just be overboost cos of the cold weather though

N1CK

i know how you feel, if i was driving it everyday it'd drive me nuts, im surprised my brother hasnt sorted it sooner tbh!!

I agree it must be MAF related, the only other thing i can think of is dirty injectors but then i dont think it'd cause the same symptoms

JamesyWRX320bhp

iTrader: (2)

na - especially as its only on low revs usuallywhen the MAF has to wrok more delicatly!!

fatboy_coach

iTrader: (1)

I'll bore you all with my story so far

I got my Scooby in April and it had this problem, took it to the main dealer (as the previous owner had always done) told them the problem, they said MAF and changed it and reset the ECU. After a month it came back and I thought about the injectors, but was told they don't go wrong so I changed the Lambda. That seemed to help for a little while, so I went with plugs and Magnecor leads and that made it much better but it's still not prefect.

I read on here that it's quite a common problem and changing the ECU can help!

Ian

Tidgy

if its still not solved ian get yourself up to scoobyclinic and get it in on the dynoa nd see whats wrong, might be able to sort it with a remap

JamesyWRX320bhp

iTrader: (2)

wheres scoobyclinic

Tidgy

bit of a treck, chesterfield, lol, although df worth traveling. might be somewhere nearer to you with a dyno and a good rep

N1CK

a remap would be more viable than replacing the ecu. shame we live in cornwall though

Tidgy

def worth traveling though lol

KenS55STI

I thought this surging was a feature of this model year car and the 'solution' is to fit an ecu from a 99 model.

A remap should sort it out, but it's an expensive way of doing it if all you want is that sorting, another ecu would be cheaper.

Tidgy

if your gonna fit another ecu it will need mapping anyway

KenS55STI

I think the 99 model ecu can be fitted straight in to a 2000 car without needing a remap.

Do a search, this has been well covered on here a number of times.

s70rjw

iTrader: (2)

https://www.scoobynet.com/general-te...-after-run.htm

theotherphil

The problem of surge/ hesitation while on boost can be caused by the wastegate duty cycle being to high. When it happened on mine, I just dropped the duty cycle down on the Apexi commander and the problem went away. Basically what happens is the boost builds and then overshoots the set point. The ECU then tries to compensate which gives the feeling of hesitation. Once the boost drops below the set point again, the ECU then tries to build it back to the set point. I could actually hear the difference in the induction as the boost built and dropped, built and dropped. It happened between 3.5k and 5k in 4th and 5th gear before it would finally settle down to 1.4bar.

I am lucky that I have the means to adjust mine on the fly. You could try giving the boost control solonoid and associated pipework a clean.

SW Sport Pilot

I had a slightly similar problem on my Y reg Turbo 2000 where it was slightly hesitant on the throttle but my petrol gauge was dropping a damn site faster than before. I took it to a subaru garage owned by an Ex prodrive mechanic after hearing about lamda sensors etc. He put an ecu scanner on it and rang me to inform me that my Cooling temperature sensor was broken, essentially the car was running on cold start cycle for a lot longer, apparently its a common fault on classics with the onset of winter, common enough for him to hold a stock of them with his stock of maf sensors, it is still slightly hesitant on the throttle which he says is due to the maf slowly deteriorating, according to him the ecu wont give an error reading when its only just starting to go on mine but when its almost ready to fail, il put a new maf on in the next service

Hope this helps

Ian

Manic Mav

My last impreza was a classic on a 2000W and did exactly the same,.Had the MAF cleaned at the dealers and all was ok from then on.
They said it was due to my having an after market KN induction kit fitted.(they fitted it)DOH.
Good luck.

JPF

iTrader: (1)

Had the same problem with my MY99 with full decat, took it round to another scoobynet members house, he cleaned the boost solenoid and reset the ecu its been fine since.