Diagnostics on 2002 WRX

[Luckyone]

I've had the WRX hanging about for 10 years now, but it's not been on the road properly in that time. It comes out to drive round the field here occasionally & seems to run ok however the check engine light has been since I bought it off my sister in law, she sold it because the light came on & she couldn't find anyone to look at it.

I have tried different tools on it over the years, I see others say they got on fine with the ELM 327 but I couldn't get that to connect at all. I have a VAG PC system that says it can read generic engine codes on other cars, but it can't connect the the WRX.

I just bought a hand held reader that says it will read all engine codes on cars from 2002, but it's saying there are no logged faults on the WRX. I tried on my 335i too as I know that has a misfire but its saying there is no codes on that either when my BMW specific code reader tells me its cylinder 3.

Looking at other code readers I see a lot say they will only read Subaru from 2007.

Has anyone got any tips?

[vxr2010]

On all the time or only when you start moving ?

[Luckyone]

vxr2010 said:

On all the time or only when you start moving ?

On permanently (comes on as soon as the key is tuned & doesn’t go out when engine starts), not flashing though. The handbook says not flashing means “an emissions control system malfunction”.

I guess that’s probably a lambda but I don’t really want to guess at faults & assume I’d still need to clear the light after replacing any faulty sensor anyway?

[vxr2010]

As subaru use their own obd software it makes it harder work to read codes , some engine codes on a basic obd are read able , but it's depends on the code and the reader , abs and emissions on a little cheap ebay code reader won't be visible , where are you based any scooby owners near you with the tech needed , I bought a bigger more expensive code reader in the end and that seems to read most codes on most cars was about 130 quid or so , other options buy a reader that they conform can read a subaru , if the cars road legal sounds like it's not then drive to a dealer , or contact a mobile mechanic just make sure he has the scooby tech to read it

[smokey mow]

I have one of these and it reads the codes on my 2004 WRX and can then likewise reset the light.

https://www.ebay.co.uk/itm/153421854196

I pair it to the car scanner app

[Konan]

Some of the basic USB readers work with Learning view, which will read the enhanced Subaru stuff as well as codes.

If you want to make quicker headway, you might want to see if there's anyone around with an OpenPort and software, you can read the raw output of the ECU that way and it can be far more helpful than just a code. There are cheap knock-off ones about - no idea how good they are.

You'll well outside of my area but you might find there's a willing enthusiast nearby that'd be willing to spend half hour on it. I would if you were nearby.

Most lambda codes would be a fairly standard fault code (emissions control systems being a big reason OBD got pushed as a standard) but if you're not reading it, I wonder if you've got something like a stuck/iffy TGV going on.

[Luckyone]

Thanks for all the replies, the car is very much stuck at home till I can get an MOT on it. I'm near Ellesmere in north Shropshire but don't know anyone else who owns a Scooby

On the plus side I have an huge amount of rust repairs to get though so there is no hurry!

vxr2010 said:

As subaru use their own obd software it makes it harder work to read codes , some engine codes on a basic obd are read able , but it's depends on the code and the reader , abs and emissions on a little cheap ebay code reader won't be visible , where are you based any scooby owners near you with the tech needed , I bought a bigger more expensive code reader in the end and that seems to read most codes on most cars was about 130 quid or so , other options buy a reader that they conform can read a subaru , if the cars road legal sounds like it's not then drive to a dealer , or contact a mobile mechanic just make sure he has the scooby tech to read it

Ah ok, I was assuming emissions would be part of the basic engine codes. The code reader I bought was sold as being for Subaru, but looking again at that sellers other listing they have that same reader in many different listings with just about every manufacture out there, so they are obviously trying to pass off a generic reader as a manufacture specific one. I sent them polite message asking if they can help, I'll probably just need to start a refund if I don't hear back from them. I may go for a better one in the end as you did.

smokey mow said:

I have one of these and it reads the codes on my 2004 WRX and can then likewise reset the light.

https://www.ebay.co.uk/itm/153421854196

I pair it to the car scanner app

That sounds promising, it's been a good few years since I looked at the apps you can get, I see there are a few for iPhone now which would make things easier for me. I had been trying crappy android tablets the kids had for 5 mins before they got broken.

Konan said:

Most lambda codes would be a fairly standard fault code (emissions control systems being a big reason OBD got pushed as a standard) but if you're not reading it, I wonder if you've got something like a stuck/iffy TGV going on.

I haven't heard of any of the other things you were talking about (some time with google required!) how ever what you said at the end about emissions followed my limited understanding - that lambda codes were part of the basic OBDII

I think the generic code reader I ended up with is rather limited, if not faulty, seeing as it can't get engine codes out of my 2007 BMW either....

[Konan]

Luckyone said:

I haven't heard of any of the other things you were talking about (some time with google required!) how ever what you said at the end about emissions followed my limited understanding - that lambda codes were part of the basic OBDII

Which was making me thing (outside of you having a plain duff reader that doesn't want to work at all...) that it could be emissions kit that might not throw a standard OBD code.

One such example are the tumble valves (TGV). They're a set of butterfly valves that sit in the inlet in order to improve emissions under cold start. If they stick, get disconnected or the position sensor goes bad, you'd get a code from the system. Only one such example, of course, but they do go wrong.

[Luckyone]

Konan said:

Which was making me thing (outside of you having a plain duff reader that doesn't want to work at all...) that it could be emissions kit that might not throw a standard OBD code.

One such example are the tumble valves (TGV). They're a set of butterfly valves that sit in the inlet in order to improve emissions under cold start. If they stick, get disconnected or the position sensor goes bad, you'd get a code from the system. Only one such example, of course, but they do go wrong.

Yes thanks, that’s very useful info.

My BM has a misfire (I can feel it all too well if I put my foot down) my old little cheep BMW code reader tells me it’s cylinder 3.

This new other reader has a section for misfires but it says there is nothing wrong with the BM, so that makes me suspicious of the new code reader.

Hopefully I can return this code reader & try a different one.

I may well be going back to look at TGVs though!

[TEKNOPUG]

Most of the cheap Chinese ELM327 readers are junk, based off the outdated original version. Try a decent one like https://www.obdlink.com/

Also, have a read here first: https://www.carscanner.info/choosing-obdii-adapter...

[Luckyone]

TEKNOPUG said:

Most of the cheap Chinese ELM327 readers are junk, based off the outdated original version. Try a decent one like https://www.obdlink.com/

Also, have a read here first: https://www.carscanner.info/choosing-obdii-adapter...

Sorry I missed that, luckily I'm ok now.

smokey mow said:

I have one of these and it reads the codes on my 2004 WRX and can then likewise reset the light.

https://www.ebay.co.uk/itm/153421854196

I pair it to the car scanner app

Great suggestion it works a treat on 2002 models too

Gave me a couple of codes, the lambda heater circuit being the exact kind of thing I was expecting to find.

The other reader was obviously junk, the seller still hasn't replied but the return has gone though ok.

I haven't done anything more that be pleased I've finally got some meaningful codes out of it after 10 years of waiting. I guess it could be something as simple as a fuse, my next question will most likely be asking for links to wiring diagrams!