Rev's dropping & stalling.

[HKS]

Hey all,

 

As i explained before I have a 2000 turbo, and its relatively standard, uprated exhaust, uprated air intake are the only mods.

 

Recently, when the car has warmed up, if i come to a stand still the car revs drop to almost 0, (sometimes it stalls) yet when its on boost, all seems to work fine...

 

Anyone had any experience with this issue?

 

Local garage and friend, (the previous owner) is also stumped by this, they've cleaned the idle control valve, throttlebody etc.. no luck it would seem?

 

Open to suggestions that don't involve my local subaru dealership diagnosing a million different options all at 1000's of ££ to "fix"

 

HKS

[Gambit]

I would look at the MAFS (mass air flow sensor) what it sounds like to me. I had an issue like this paid for diagnostics you name it. all came back with no fault. Changed the MAFS, and just like magic it went away. You can clean them so I have been told but also told it can damage them  so I will leave the risk up to you. Could be something else but worth a shot 1st

[Scooby Pete]

I 2nd the maff idea, See if a mate who has the same maff can come round and swap them over to test it.

 

You can get mafs pretty cheap these days.

[scooby gee]

i have the same issue at the minute done it a couple of times on my way home and ive just put a new maf about 3 weeks ago

[HKS]

i have the same issue at the minute done it a couple of times on my way home and ive just put a new maf about 3 weeks ago

Hey thanks for the advise Gambit & pete few other forums said the same thing, Will look into that.

Scooby Gee if you changed the MAF few weeks back you might wanna check your idle control valve, or if your Battery hasn't even connected in a while I could've reset the ECU maybe?

[Gambit]

Not a problem mate hope it helps. Scooby Gee like HKS just said would take a look next at the Idle control valve so your sort of working back if that makes sense. I know its a pain but on the Brightside I was playing about with the same problem for over 8 months before I sorted it ;)

[Adam]

Likely to be one of two things... As said above, a MAF sensor failure can cause this and is most common on early phase II engines that used a cheaper sensor. Although if this is the cause you would probably have some hesitation under power too. The other thing that can cause this is an air leak from the inlet manifold or supporting componants. Check the dump-valve first as these can get weak over time, and if it's the type that bolts to the intercooler check the gasket seal. Next check all the airline pipes for cracks as they can perish over time.

[Gambit]

Agreed get a spray bottle soapy water and spray the pipes and area's that Adam has said, you will hear the engine noise change if it has a cracked pipe. or bad seal

[Scooby Pete]

Yeah I was thinking about this and thought it may be the crank shaft sensor or a leak in the induction system.

Do you know how to do the CEL check?

There is a green male and black female plug under the steering wheel you connect turn on the ignition and watch the CEL flash like morse code to give you the fault.

This thread on scoobynet shows you how and has the fault codes as well.

http://bbs.scoobynet.com/general-technical-10/793200-check-engine-light-flashing-help-please.html

May point you in the right direction.

If you car is the later one with the OBD connector you have to get someone with a reader to check the codes for you.