Hope someone can shed a light on a recent problem on my 99 Sti wagon
About 2 months ago car was mapped by JGM and achieved 368/347
All was great since , apart from the last few days when I am now getting the these problems

1) under normal driving , when coming to a stop or coming up to roundabouts/ lights etc, once car is in neutral it's bringing on the ignition lights as if it wants to cut out , revs dip to nearly zero, then most times it picks up and sits at about 750rpm, when it was mapped, revs at tickover were about 900

2) car was boosting no problem and was mapped to 1.5-1.55bar , it's now hitting fuel / boost cut at 1.4 under acceleration

Car has performed great with no other issues until now
I've checked pipes for splits and loose connections , icv but seem to now be at a head scratching stage
Can any one help with either of these issues and point me in any other direction as to what to check next??
Thanks in advance

 

What ecu are you running ?

 

If we ignore the fact its been mapped then those are the same symptoms I had and required a new MAF and lambda sensor.

 

I had a new maf fitted at the same time as the mapping
The ecu is a apexi FC, with a avcr also fitted

 

Anyone?

 

Is the spark getting blowen out....take a look at the plug gaps...that worked for me..

 

Cheers matey I will check these, abiet these wee new plugs fitted just before mapping and have been fine for about 2 months

 

Could be a fuel pressure problem. Do you have an uprated fuel pump?

 

Assuming tmic - have you checked the pipework underneath?

 

It has a new Scoobyworx250 updated pump and I'm running a fmic with all pipes/ joints have been checked

 

Thanks for that , I will take icv off and clean
I don't have the hand controller to alter parameters with the apexi ecu only the avcr

 

What was it

 

Did u rectify the problem..im having same symptoms,been told by zen performance it needs a new maf...ordered one for tomorrow..will let u no..once thats sorted ans a vf35 i will get it mapped

 

Not fully sorted at the moment
Car is booked in for JGM to check apexi ecu and see if anything is wrong
I have took off the dump valve and blanked off the outlet it fastens to the fmic pipe work , that seems to have cured the 'cutting out' at low revs
But I'm not 100% it's that
Checked all I can including icv, all hoses on fmic, from turbo inlet manifold , injector seals etc for air leaks and nothing
My naff was a new one one the day of mapping , so it's only 3 months old max
It may be that or boost solenoid or ecu based
But it still ticks over when warm 200rpm lower than it did when it was mapped
Plus the over run pops n banks have also disappeared !!
I will let you know after Wednesday what the outcome is
Neil

 

if pops and bangs have gone sounds like a fueling issue for def, maf can be a week, a day or a year old and still fail so dont assume its ok.

my classic blew 3 of them during mapping before i went to mafless autronics, mine was a 99 uk trubo, but pretty sure its the same maff isnt it? (someone correct me if im wrong)

 

Check the vac lines located at the left side intake manifold piping. It certainly screws with idle and running.

 

Well car is now finally running perfect!
Simon had the car over at SRR today and found the small vac pipe off fuelab pressure reg wasn't airtight
And the major thing wrong was.........
The ecu had got wet! And totally lost its previous map
So must have been on a standard base map !!
Thanks to simon, Charlie , CJ it had to be repaired and re install a map to suit all my mods
As ever they went above and beyond to help
Car now drives perfect and now has 374.9bhp !

 

What you want on that is a sc40 billet lol good to hear she sweet again and nice figures

 

This is the graph from today

 

Lol cheers
I have to justify today's spending with her indoors , let alone another turbo !

 

Say to get through next mot I need a turbo lol. I know exactly what you mean

 

how did it get wet?

 

Water ingress from either floor or down window seal or another way in
Still not fully located where from,
Heater matrix is all good with no leaks

 

so no we patches or anything like that?

 

Slight wet on the carpet under foot mat
No pools of water tho
Will be exploring where it came from over weekend
But is it advisable to cover ecu with some sort of bubble wrap or plastic to stop any moisture????