Ok guys and girls..need your technical help.
Have put off asking on here first,because I thought my local garage would have an idea, but they seem stumped and talk about heat soak and suggest all kind of wierd and wonderful heat shield/boxes etc, which I dont think is the answer.
The problem
In this warm weather, scoob builds up the engine temp quite quickly especially when idling in traffic (london). Engine temp gauge (not the main one, the oil temp gauge in a cluster of three linked directly to oil sump by sandwich place)
When oil temp reads anything between 90-103, car develops this problem.
Start moving and once it comes on boost, i get a strange whistling/sucking noise and i have no boost. the car feels sluggish and wont go over 3.5/4k revs. Tends to happen in 3/4/5 gears and I have to just idle along until the temp drops to around 85-90. only then do a get a little sort of hesitation and all of a sudden boost is back and I am back to normal.

suggestions so far

Apart from people suggesting heat soak, other suggestions have been leaky or holed radiator hose or a problematic hose somewhere in the system, leaking coolant etc.

I have checked the coolant and seems fine.
I dont know whether this will happen in colder weather, but TBH i cant wait until it gets colder to see if it goes away..this i feel is not related to the weather.

I have done some major mods over the last 5 months, but I feel they are all improvements rather than problem bringers.
I have an uprated STI intercooler (not the sti8), Powertec induction kit, TD028 turbo, downpipe is lagged etc etc.

So any bright sparks out there had similar problems or have any clues??
It is doing my pigging head in, so any help would be appreciated.

 

Sounds like u have a boost pressure leek when your car is getting hot, could be a pipe opening up when hot then closeing when cool.???? Worth a try good luck.

 

Sounds like your car is running in 'safe' mode, thats why it won't rev. Also check the boost solenoid, that could have something to do with it. Get really bunged up on some cars, need blowing thru with high pressure air.

HTH

Dan.

 

thx for the replies so far
will check out those ideas, dont think its running safe mode, as the rest of the time it runs fine, normal boost, normal power.

any other bright sparks?

 

Are you able to do an ecu fault check on your cars (I know you can on alot of cars) it might point you in the right direction.

Does sound like abit of a boost leak. They can play havoc sometimes.

 

Have a bump matey... we need to resolve this one

 

cheers si, need all the help i can get

 

major mods....there,s your problem new turbo... start there, intercooler..next....induction kit.......


glad you lot dont work in mass production .....if your going make changes, do it in steps, that way you can easliy identify where and when aprob occurs....

incidentally, did you actually check that the mods are compatible with each other?? does the ic flow enough air? too much? does the obrut need a set boost pressure?? is the maf fubarred? you see! too many mods & permutations

sell it and by a nova

Mart

 

cheers for that mart you numptie...
You started off so well, giving what sounded like good advice and then ruined it all...waste of time writing all that.

All the mods done are all well within the tolerance of the engine and are more importantly all chnages which have been done countless amounts of times by other owners on here, albeit not exactly in the same manner or combination as myself.
All the airflow modifications were added after careful advice and inline with some common sense. In fact my recent map was carried out with the airflow setup that I had on the car and during the map, I experienced no problems whatsoever with boost.
This problem is one that has just manifested recently and probably compounded by the hot weather.

To be fair to your comments, the MAF sensor has not been checked and that may be a likley candidate, as are the possibilities of leaky pipes and boost solenoid.

My question was really aimed at anyone who has experienced similar issues, me listing the mods I had done was more to give people a better idea of the setup in case there was the remote chance that there was something blindingly obvious (though I am sure it would have manifested itself earlier)

 

Wow someone else is having the same problem as mine ,

I'll start by saying it REALLY doesnt sound like anything to do with the mods youve had done mate , i've been having the same problem on my 03 wrx and that is pretty standard ( at the mo ) all i have is a h&s bb and panel filter ,

And on my way to and from leman this year i had the same problems , like you say it comes and goes but still quite worrying , and when you do finally get boost and revs did you find it was like being thumped in the chest and you was away ,

I'll keep a close eye on this thread as i too have not identified the problem as yet ,

hope this clears up the mods thing ... Dave

 

thank god (not in that way mate, you know what I mean) that someone else has the same problem as me. I thought it was me going slightly mad and everyone i spoke to just seemed to either have no idea or thought i was losing the plot !!!

didnt think it was the mods i had put on, but obviously i couldnt rule them out.
really need to get to the bottom of this, as i dont want to go anywhere near santa pod until it is sorted.

if i get the problem sorted, i will keep you informed

 

same as mate olney scoobies are having mine on wednesday for a diagnostic hopefully be clearer then .i'll do the same as you and i'll let you know whats going on

Dave

 

Do you have an aftermarket dump valve? The piston in the dump valve may be expanding under heat and getting stuck slightly open.

 

yes i do, please dont tell me that is it, some ppl i know would have a good laugh if it was that !!!
its a bailey one

 

This is just too uncanny tony i took my bailey dv12 dump valve off after speaking with you earlier and so far so good , i cant beleive it could be that and theres two of us sh#tting ourselves over the same thing .

I'll keep you posted on the cars aparent resolved problem , ( fingers crossed )


Dave

 

cheers dave, you may be a ray of shining technical brilliance amongst all the rest of mad idea's

i will doing exactly the same as you suggest and putting the dump valve back to standard tomorrow (thx god i kept the original)
if it dosent work, then nothing ventured, nothing gained, but if it cures the problem, then i owe you a pint

thx
chris

 

dave and davey
well done you two
Problem solved, it was the bailey dump valve sticking. have put the recirc one back and all well. only thing is i need the VTA to flame . so will run it like this for a while until I can source a better dump valve. liking the forge ones, bit pricey, but seem stronger springs.