Trout

iTrader: (1)

Benny Boy managed to con me - well Truda - into forking out £25 for Training WRX.

It's actually a good read, probably a bit light for Firefox, but for most of us ignoramii it's certainly worth it.

For example, it tells you how to do an ECU diagnostic without the Select/Detect monitor - it also explains how to properly reset the ECU, takes about 5 mins. I guess I can't post it here as I would be infringing copyright but you could email me...

Doing this has helped me confirm my cold start problem is due to a faulty sensor, although I don't know which one at least I can be firm with the grudge when I take it in to be checked!

Cheers,

David

PS So, Benny, that'll be 15% off the clutch then

[This message has been edited by Rannoch (edited 25-11-1999).]

firefox

Dave..

You should be able to tell which sensor by reading the error code off the flashing MIL (engine light)

I can give you the codes if you want..

I'm not above any book or source of info... I'm not a tuner.. or mechanic.. just an enthusiatic Scoob owner... :}

Pity ya not local.. we could have plugged the Select Monitor in...

J.

ps - Have you confirmed its not the idle valve ? what was the duty cycle of it when cold ?

Trout

iTrader: (1)

Well...

...to start your list a 23 on an STi V is a faulty AFM

Jay, still waiting patiently by my inbox for the codes of an STi V - looking forward to confirmation of what Park Lane think

David

[This message has been edited by Rannoch (edited 26-11-1999).]

DYNT

Code 23 - there might be an air leak somewhere ... might not be the AFM fault.

This happen a few time to my customer Subaru. So have it check ... all the joint.

AFM .... is expencive.

Cheers.

Trout

iTrader: (1)

Dynt,

sounds like a good idea - is it possible that with the increased air flow from the Induction Kit that it might fool itself into thinking there is a leak?

Cheers,

David

PS Can you confirm that 23 is AFM/Air leak?

Mark Barrett

Guys,

Sorry for my ignorance, but where have you managed to get information on Scooby Codes/ECUs etc??

I have been looking for this kind of info and failed miserably so far.

Any pointers would be appreciated.

firefox

*Grins*

What Year/Model ?

I'll email them to you..

J.

DYNT

Trouble code 23 - Mass Air Flow Sensor

Content of dignosis - 1. The MAF signal is abnormal.
2. The harness connector between the ECU and MAF sensor is in short or open.

Trouble Symptom - 1. Erroneous Idling 2.Engine stalls 3.Poor driving performance

Anything else I can help u wit????

Trout

iTrader: (1)

DYNT,

thank you very kindly for the update - unfortunately none of these symptoms are obvious except for poor start on very cold days.

The car runs very strongly once warm, idling is fine and it never stalls.

Stumped.

Thank you anyway for your help.

I will check all the wires and hoses and let you know if I fix it.

David

Bob Rawle

The maf usually has built in temperature compensation, if this is playing up then it will think that the air temp is different to reality and so the cold start mixture will be wrong. As the engine warms up the temperature compensation becomes less important as the underbonnet temp is then higher and hence the temp. of air flowing thro' the maf.A small amount of callibration error could cause the effect that is descibed.

Just a thought

[This message has been edited by Bob Rawle (edited 26-11-1999).]

Trout

iTrader: (1)

Bob,

thank you for that. It is quite possible that this has been a problem from new as the car was acquired in March and barely used until May - and then it was driven a lot - but the weather was warm(ish) until I noticed the problem the first frosty day in October.

I presume there is no long term problem with this?

Cheers,

David

firefox

Howdy...

If it is the temp compensation...or anything to do with the MAF...

Then the long term solution is ....erm.. a new MAF..

J.

ps - Assuming you cant clean it (if it is dirt related)

Trout

iTrader: (1)

Howdy doody,

plugged in select monitor today - a big thanks to Merv at Power Engineering who was very friendly and helpful...

Read memory showed code 23, but when car was running there were no faults showing at all. All sensors, idle control valve, everything was working A OK!

Will try and swap out MAF for an alternative to see if this is the fault, or it is something else.

Bluddy complicated cars these. Not like my Mini Cooper

Rannoch

Benny Boy

David

Everything was working fine no doubt as the car was warm.

I meant to say that you would have to do it from the cold start. That would entail leaving the car overnight in their garage so that when they started it for the FIRST time they could run a diagnostic.

Ben

Ben

firefox

Howdy...

Was the car cold when you were at PE?

It does sound like a duff MAF...

You need to check the idle valve when cold...check the duty-cycle of it...

Changing the MAF should eliminate that variable once and for all

J.

Trout

iTrader: (1)

Thanks guys,

I am arranging to leave it overnight later this week.

Then we'll know once and for all - possibly.

I only went in today to have a general health check with the select monitor to make me feel comfortable with the car generally - which Merv did.

Cheers,

David

Bob Rawle

A temperature compensation problem will not necessarily show up on the select monitor,if you still don't get the result then try a substitution ... try and find someone to let you try their maf instead of yours.

Trout

iTrader: (1)

SORTED!



My car started first time this morning and is now showing no faults in read memory.

The problem - the HKS Air Fuel Ratio module!

The only reason why I had not thought of this earlier was that I thought that it was spliced into the Lamba circuit, not the MAF circuit. However, perusing the HKS catalogue last night, and being prompted by Firefox, I unspliced it and the car started first time.

This would explain why the problems were asymptomatic for a MAF, although the MAF circuit was the read memory fault.

So, it has taken a long time for me to fix it, and I have learned a lot about the car - thanks to all of you who have shown patience in volunteering your views and potential solutions.

Took the car for a long blast with no problems and read memory was clear. No faults.

Cheers,

David

[This message has been edited by Rannoch (edited 28-11-1999).]

firefox

HOORAY!!!!



J.

ps - Another happy customer