Subaru Problems (help/ideas please)
Discussion
The Legacy developed some issues tonight (1997 TS-R EJ20 na manual)
After being parked for maybe an hour (had seemed fine before that) started it up to go home, once moving noticed the 'check engine' light was on. I thought thats odd, so stopped, turned it off, restarted. light still on, and when I stopped at the next intersection (maybe 50m away) it wouldn't idle and died. Got mates to push me round corner, waited a while, tinkered a bit, found battery connections were loose (no idea why, maybe from last service at dealer). Tightened them up, started up, idling real rough/lumpy then gradually losing revs until it dies. No 'check engine' light though. checked a few other things, started up again, idled a bit rough but better, with 'check engine' light on again. decided to try and limp it home, made it 4 or 5 km before it gave a cough/pop sort of sound and lost pretty much all power. Got Dad to come tow me home. hmmm.
Tried disconnecting battery for 30 min in garage to reset ECU in case loose battery connections had messed it up somehow but no improvement really. Idles lumpy/rough and quickly loses revs until it dies. Also smells very rich with unburnt fuel at the back when trying to idle. Also noticed that the oil level seems quite a bit higher on dipstick than usual, but not sure if its related or just me being paranoid. Oil still nice and clean etc.
My thoughts are:
a) MAF sensor?
b) Coil pack? (/s)
c) Something nasty I haven't thought of?
Anyone have any ideas/experience of similiar issues?
Also posted in JapChat
After being parked for maybe an hour (had seemed fine before that) started it up to go home, once moving noticed the 'check engine' light was on. I thought thats odd, so stopped, turned it off, restarted. light still on, and when I stopped at the next intersection (maybe 50m away) it wouldn't idle and died. Got mates to push me round corner, waited a while, tinkered a bit, found battery connections were loose (no idea why, maybe from last service at dealer). Tightened them up, started up, idling real rough/lumpy then gradually losing revs until it dies. No 'check engine' light though. checked a few other things, started up again, idled a bit rough but better, with 'check engine' light on again. decided to try and limp it home, made it 4 or 5 km before it gave a cough/pop sort of sound and lost pretty much all power. Got Dad to come tow me home. hmmm.
Tried disconnecting battery for 30 min in garage to reset ECU in case loose battery connections had messed it up somehow but no improvement really. Idles lumpy/rough and quickly loses revs until it dies. Also smells very rich with unburnt fuel at the back when trying to idle. Also noticed that the oil level seems quite a bit higher on dipstick than usual, but not sure if its related or just me being paranoid. Oil still nice and clean etc.
My thoughts are:
a) MAF sensor?
b) Coil pack? (/s)
c) Something nasty I haven't thought of?
Anyone have any ideas/experience of similiar issues?
Also posted in JapChat
Unlikely MAF problem at that year. And generally MAF wont throw a CEL light.
Coils wont either, although again, the coil pack on a 97 car is generally quite reliable. Thats not to say it cant be faulty.
Under the steering column, there are a couple of diagnostic connectors that will flash up fault codes, which may help identify the problem
Dont recall all the details off the top of my head, but if you ask or search here, everything will be covered.
http://legacy.manxforums.com/forums/i
Coils wont either, although again, the coil pack on a 97 car is generally quite reliable. Thats not to say it cant be faulty.
Under the steering column, there are a couple of diagnostic connectors that will flash up fault codes, which may help identify the problem
Dont recall all the details off the top of my head, but if you ask or search here, everything will be covered.
http://legacy.manxforums.com/forums/i
Well it didn't get any code I could make out, just kept flashing at me constantly. Would error codes have been erased by me leaving th battery off for 30min to reset the ECU last night? hasnt been driven since then but has been started and no change in engine. (idles really rough, running very rich going by the smell, then loses revs and dies).
OK realised I was using the wrong connectors, green is diagnostic connectors which just flash, black gives error code 23 (long-long-short-short-short)
Anyone know that one?
Well I googled and found that its the MAF code, but someone on the other thread has kindly pointed out that I got code 23 because I unplugged the MAF before to check it out. doh!
Any further advice?
Anyone know that one?
Well I googled and found that its the MAF code, but someone on the other thread has kindly pointed out that I got code 23 because I unplugged the MAF before to check it out. doh!
Any further advice?
Edited by GravelBen on Friday 2nd February 22:44
a scanner is the best way forward - variable sensor readings are read at the ECU as OK sometimes even if they're not - the ECU isn't clever enough to recognise parameter changes unless they're really wild or there's no signal at all - even if no code is set the component live readings can be studied to decide where the fault lies
this sounds like an O2 sensor, CTS sensor or MAF sensor fault - the scanner live readings will show you the way
good luck
this sounds like an O2 sensor, CTS sensor or MAF sensor fault - the scanner live readings will show you the way
good luck
Most scanners wont read Jap stuff of that age, and anyway, a Scantool is only as useful as the persons ability using it.
Although......this should work on your car.
www.rslibertyclub.org/forums/showthread.php?t=58031
It isnt a scanner, and if you dont know how to use the readings, it can be meaningless in terms of trying to diagnose a fault.....
Although......this should work on your car.
www.rslibertyclub.org/forums/showthread.php?t=58031
It isnt a scanner, and if you dont know how to use the readings, it can be meaningless in terms of trying to diagnose a fault.....
motorwise said:
this sounds like an O2 sensor, CTS sensor or MAF sensor fault - the scanner live readings will show you the way
I'm thinking MAF is less likely now, as the MAF code came up only when I had disconnected it, and having cleared it and tried starting again it hasn't come up again, so the ECU isn't picking up anything there. It didn't run for any longer with MAF disconnected than connected either.
where are the 02 and CTS sensors? could try starting with each of them disconnected and see if it changes things.
The car is under warranty but nobody will be open to check diagnostics etc until monday, and I can't get hold of the warranty people until then anyway. So its not urgent, but I still hate not knowing whats wrong with it.
IMO, neither CTS or O2 sensor would give the symptoms you describe.
dodgy O2 will have minimal effect on the cars running, although it will drink more fuel.
CTS would usually effect cold start and running, than anything else, although it could have an effect overall....again, I doubt either of them would throw a CEL on your age of car.
Reset the ecu as mentioned above, and see what codes are present after a short drive, or at least run the engine for a minute or 2.
dodgy O2 will have minimal effect on the cars running, although it will drink more fuel.
CTS would usually effect cold start and running, than anything else, although it could have an effect overall....again, I doubt either of them would throw a CEL on your age of car.
Reset the ecu as mentioned above, and see what codes are present after a short drive, or at least run the engine for a minute or 2.
I've reset the ECU but it will only run for 20-30 seconds before it loses revs and dies. Can keep it going a little bit longer with the throttle than it will just idling but it still dies pretty quickly (so I can't drive it anywhere). It isn't showing any fault codes after starting a couple of times though.
The CEL only comes on some of the times I try starting it, but not much else changes, if anything it runs worse when the light is off.
The CEL only comes on some of the times I try starting it, but not much else changes, if anything it runs worse when the light is off.
stevieturbo said:
IMO, neither CTS or O2 sensor would give the symptoms you describe.
dodgy O2 will have minimal effect on the cars running, although it will drink more fuel.
CTS would usually effect cold start and running, than anything else, although it could have an effect overall....again, I doubt either of them would throw a CEL on your age of car.
Reset the ecu as mentioned above, and see what codes are present after a short drive, or at least run the engine for a minute or 2.
dodgy O2 will have minimal effect on the cars running, although it will drink more fuel.
CTS would usually effect cold start and running, than anything else, although it could have an effect overall....again, I doubt either of them would throw a CEL on your age of car.
Reset the ecu as mentioned above, and see what codes are present after a short drive, or at least run the engine for a minute or 2.
so the CTS doesn't affect the mixture?
so the O2 sensor doesn't affect the mixture?
so the MAF sensor doesn't affect the mixture?
all these sensors affect the mixture and can cause the symptoms described sometimes throwing a code sometimes not which is why the scanner is needed - trust me I do this for a living
motorwise said:
stevieturbo said:
IMO, neither CTS or O2 sensor would give the symptoms you describe.
dodgy O2 will have minimal effect on the cars running, although it will drink more fuel.
CTS would usually effect cold start and running, than anything else, although it could have an effect overall....again, I doubt either of them would throw a CEL on your age of car.
Reset the ecu as mentioned above, and see what codes are present after a short drive, or at least run the engine for a minute or 2.
dodgy O2 will have minimal effect on the cars running, although it will drink more fuel.
CTS would usually effect cold start and running, than anything else, although it could have an effect overall....again, I doubt either of them would throw a CEL on your age of car.
Reset the ecu as mentioned above, and see what codes are present after a short drive, or at least run the engine for a minute or 2.
so the CTS doesn't affect the mixture?
so the O2 sensor doesn't affect the mixture?
so the MAF sensor doesn't affect the mixture?
all these sensors affect the mixture and can cause the symptoms described sometimes throwing a code sometimes not which is why the scanner is needed - trust me I do this for a living
CTS does, but generally sypmtoms show when the engine is cold. Less so when hot, and its hot when he said this fault started occuring.
O2 does....Not when cold though. Not during full throttle, Not during high rpms.
If it was the O2, you could easily force open loop, so it has no effect on how the car runs.
And as its cold now, O2 would have NO effect on cold starting/running whatsoever.
MAF does, of course it does. Again, 97 models of these cars are very reliable in terms of MAF. Just because 99/00 models fail all the time, people jump on that bandwagon and say it for all subarus.
Out of curiosity, what scanner do you use that will plug into the 97 cars ?
Ben.
O2 sensor is located in the exhaust, near the engine.
CTS is awkward, and in an aluminium water pipe that passes underneath the inlet manifold. It usually has a brownish coloured plug on it. Not easy to get at, although might not bad as bad on a n/a car as a turbo one.
MAF you already know.
stevieturbo said:
CTS does, but generally sypmtoms show when the engine is cold. Less so when hot, and its hot when he said this fault started occuring.
It wasn't stone cold but definitely wasn't up to temperature when the problems showed up - had just been started after parked up for probably an hour or so (and only a short drive from cold before that) and NA Subarus seem to cool down very quickly.
Out of interest, why would the coolant temperature sensor have that effect on how the car runs? Or is there a different 'CTS' that I'm mixing it up with?
stevieturbo said:
Ben.
O2 sensor is located in the exhaust, near the engine.
CTS is awkward, and in an aluminium water pipe that passes underneath the inlet manifold. It usually has a brownish coloured plug on it. Not easy to get at, although might not bad as bad on a n/a car as a turbo one.
MAF you already know.
Cheers
GravelBen said:
[quote=stevieturbo]
Out of interest, why would the coolant temperature sensor have that effect on how the car runs? Or is there a different 'CTS' that I'm mixing it up with?
Out of interest, why would the coolant temperature sensor have that effect on how the car runs? Or is there a different 'CTS' that I'm mixing it up with?
CTS will affect mixtures, mostly when cold. So the car knows it needs "cold start" etc in a similar fashion to the choke on older cars.
When cold it generally needs more fuel, a little more timing, and more air to run smoothly, until it reaches its normal operating temperature, when most temperature related compensations will be virtually zero.
A faulty CTS will usually default at one end of the scale or the other, but it can give spurious readings too. But when warm, the engine can usually handle rich mixtures etc without any real running problems.
It cant handle cold running without the extra fuel though, so it would make starting and running quite difficult. Although once it had a bit of heat in it, it should still run well enough, that it isnt stopping all the time.
Without seeing the car, its incredibly difficult to diagnose.
motorwise said:
stevieturbo said:
IMO, neither CTS or O2 sensor would give the symptoms you describe.
dodgy O2 will have minimal effect on the cars running, although it will drink more fuel.
CTS would usually effect cold start and running, than anything else, although it could have an effect overall....again, I doubt either of them would throw a CEL on your age of car.
Reset the ecu as mentioned above, and see what codes are present after a short drive, or at least run the engine for a minute or 2.
dodgy O2 will have minimal effect on the cars running, although it will drink more fuel.
CTS would usually effect cold start and running, than anything else, although it could have an effect overall....again, I doubt either of them would throw a CEL on your age of car.
Reset the ecu as mentioned above, and see what codes are present after a short drive, or at least run the engine for a minute or 2.
so the CTS doesn't affect the mixture?
so the O2 sensor doesn't affect the mixture?
so the MAF sensor doesn't affect the mixture?
all these sensors affect the mixture and can cause the symptoms described sometimes throwing a code sometimes not which is why the scanner is needed - trust me I do this for a living
What he said.
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