can't find what 's wrong, help needed

[vertigone]

hello,

After a lot of research I can't find a cure to this :

533 -Idle regulation adaption limit exceeded (N71)
Adaptation Limit Not Reached INTERMITTENT

When cold the car run perfectly but after some drive, the idle goes very down almost stall engine when stopping ... No more power and boost, running very rough

I've already change 3 times the ISV but no luck

I forgot to say that when i hold Idle at 1500 rpm when warm it goes up and down and show isv defaut code on vagcom
Very Strange ...

[Biggss2]

If I remember right, the g28 aLways flags up with the engine turned off?! I'm sure someone can confirm this

Does the car misfire/splutter under load/acceleration?

Mine done this, with similar codes, ran fine under 3000revs and when cold, then started playing up on boost/warm- it turned out to be a faulty coil!

I don't know if that was of help, but just sharing my experience, not a techi by any means!

[vertigone]

Bigss2 thanks for this imput
on 3b motors it's only one coil with distributor but mine got 215 000 kms, it's perhaps time to change it !

The symptom you describs is correct : car sometimes misfire/splutter under load/acceleration but never in cold conditions !
I've already done boost leak test and nothing found


fi : the G28 comes up when engine is off but trouble code is : 00513 - Engine Speed Sensor (G28): No Signal

[orangepeel]

look on s2 central net .helps put you in the right direction of were to look .and post up what you find

[vertigone]

S2central is already in my favorites bookmarks since i've the car (3 years now)
First thing i'll try : change ECU and coil pack

keep you updated

[orangepeel]

have you looked on sjm auto-technik some good trouble shooting tips on there

[Greg_S]

Have you checked the resistance and condition of cables from ISV etc to ECU?

[vertigone]

Have you checked the resistance and condition of cables from ISV etc to ECU?

nop, I've to say i'm not very familiar with electric things
any help to this ?

[vertigone]

Today I change my ECU to stock one, see if it makes any difference ...

[vertigone]

ok after 2 days runing with stock ecu, it finally did the same tonight
the difference this time is that only one default comes up :

533 -Idle regulation adaption limit exceeded (N71)
Adaptation Limit Not Reached INTERMITTENT

anyone can explain how to test wires from ISV to ECU ?
I must have a short circuit somewhere !

[Greg_S]

If you have a look on S2central.net paul has added wiring diagrams showing the routing for pins on ECU out into the engine bay along with the wiring diagrams. If you take the connector off the ecu and buzz them out from there to the ISV connector you should be able to track down your bad connection.

HTH

[vertigone]

I'm in Holidays Can't check for the moment
But a member pm'd me a Nice Idea :
N80 valve Can cause poor Idle
Have to check This one too

[vertigone]

I forgot to say that when i hold Idle at 1500 rpm when warm it goes up and down and show isv defaut code on vagcom
Very Strange ...

[prj]

Have you tested for boost leaks?
Have you cleaned the ISV?

[UrS4boy]

There is some N71 ISV and N80 Evaporative emissions cannister info in the diagram linked below. Click on the labels near the top right. (all the other labels are "hot" as well for future reference):

http://members.shaw.ca/speedtek/UrS%20Engine%20Bay%20Device%20Map.html