Hi all,
My 95 wrx wagon has twice failed drastically on emissions even after iv replaced the lambda and checked plugs..reset ecu and took it for a few spirited drives..
Heres my failure stats..
Fast idle. . Co2 max limit..0.3 , actual value 8.070
Hc max limit. ..200 actual 273
Lambda value between 0.97-1.03 , actual 0.78

Second fast idle are of a similar as this..

Can anybody shed any light on whats going wrong and what can I test to verify if everything is working?

 

Running very rich! Any other mods to the exhaust or intake?

 

Yea has it been De catted, failing that find a friendly mot shop...

 

Standard cat and standard air intake..only difference is I have an esl daughter board..
And I dont know of any friendly mot garages :'(

 

That is an insanely rich idle. I can only imagine something has changed since it was mapped or a key sensor is up the duff, but I do no idea about the ESL board. Is it running MAFless or with MAF?? If with MAF and you can't get someone out to investigate the map, I'd have a go at creating a vacuum leak at the manifold that lets more air in that what is measured, leaning it out so that you can pass the MOT, however without a C0 monitor you are going to struggle.

You probably need to get the map checked anyway as if it is doing this across the usable rev range and throttle positions you might end up with bore wash and worse problems than an MOT failure.

 

Im not getting any sensor fault codes..I think il unplug the esl board for a start..
The other thing is how can I tell if the lambda sensor is working because with that reading being so far out im wondering if that is contributing to my fail

 

Am I right in thinking it isn't the live mappable ESL board?

 

Iv just had a look and its the v1.0 board?
Can you shed any light on this andy?

 

to my way of thinking to be that rich it's one of 3 things
unmeatered air ie air leak after maff
ecu temp sensor
stuck injector
try those 3 before you spend any sill money

 

Ok il look into those..how can I unstick an injector if that is the case?
Also it does struggle to fire first time from cold and smell very fuelly if that helps with any theory's

 

not sure how to unstick them, but the cold part sounds like temp sensor. you say you changed 02 was it new or s/h if s/h test it in a vice using blow gun method, there is a well usefull video on you tube on how to do it, but a unmeatered air leak will cause car to run well rich and i mean rich enough to wash the bores so get if fixed before you drive it to far

 

v1.0 is not mappable. Unless someones played with the eproms it's similar to a 6k or z4 map with a bit less ignition and a bit more boost, so it's unlikely to be the problem. Easy to check though, just rejoin j1.

Your lambda reading is about 11.5:1 AFR. If your narrowband lambda sensor is working it should bring it back to stoich at fast idle. I'd probably start there.

 

Lambda is a brand new 3 wire zirco which I had sitting in its packet.
It doesn't seem to have any effect when its disconnected (when the engine is at running temp)

 

Can anyone shed any light on the fact that when I have thr lambda disconnected it starts alot easier from cold..also iv ordered a new (geniune subaru) coolant sensor..hoping this helps.

 

Bump

 

if I was at home I could tell you exactly what to try as I have a bottle of it! - done it on a few of the cars that have been high on emissions.

its a fuel additive you put in a full bottle with only like a £10 of petrol and that has cleaned through a few of the cars that have been high on emissions, will get the name on Monday for you

mixed reviews though on what people think of it, worked good for me on a few cars none of them were scoobs though

 

Well anything is of help so il give it s go when I know what its called ;-)
I have to go back on what I said on my last comments as I tried the scoob this morning (its been garaged since its fail) and with the lambda disconnected it still didn't start first time..
Hoping for improvements when I replace coolant temp sensor

 

Wouldn't that point to the lambda sensor perhaps? I know you replaced it but there's a possibility it's a duff one!

 

Im going to do the bench test on my original lambda to see how that fairs..just replaced my coolant temp sensor and it seems to have resolved my cold starting issue..car fired up from first turn of the key!

 

Still waiting on this additive ;-)

 

Woohoo I got it through. .seems like the coolant temp sensor was the main culprit
So iv replace that along with a new set of pfr6b plugs and the turbo inlet hose (donated by a mate)
As mine was splitting at the turbo end where the jubilee clip sits..
Will post latest emissions data when I get it to show how much difference it has made :-)

 

Amazing a coolant temp sensor can make that Mich difference to the emissions, glad it's sorted, has it passed mot now then

 

Yep iv got a full years ticket now ;-) I couldn't beleive it but heres my emissions pass results..
CO: limit 0.300 , actual 0.268
HC: limit 200 , actual 65
Lambda 0.993

 

Did you put any additive through it, I was looking at a bottle of redex today was half price but decided not to

 

No additives mate, just a few gallons of shell nitro plus and gave her a good half hour run out before emissions test ;-)
But in typical style my fuel pump packed up literally a few hours after being road legal!