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Discussion Starter #1
Hi peeps,

OK bare with me, but I need a bit of help.

I took 1 standard R32 that was running fine. I had it chipped to remove the speed limit and the boost limit and tweek the fueling and ignition a tad.

We then fitted a bleed valve between the standard boost solenoid and the actuators and tweaked the boost to 1 bar.

Start the car all is fine, but after a while (and this while totally varies) the boost drops down to 10 psi and the idle raises to about 1100rpm. The idle also seems a little rough even though it is above the 950 rpm norm.

If I stop and restart the car all is fine again for a while.

Oh the only other thing I did was fit a pair of Apexi air filters.

The car drives and sounds perfect apart from what is described above.

My thoughts are:
An air leak (I have checked everything that is accessable, and it odesn't do it all the time)
Faulty standard boost solenoid?
 

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Discussion Starter #2
Do people normally bypass the standard boost solenoid altogether. when they use an sftermarket boost controler or bleed valve or whatever??

All sugestions, greatly received.

Cheers

Sean..
 

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May help if you do an ECU reset.

Disconnect the battery. Leave it for half an hour. Pump the brake pedal a bit (trying to illuminate the brake lights will discharge and residual power left in the car). When you reconnect the battery the ECU will have reset and may (or may not ;) ) sort itself out.
 

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Discussion Starter #4
Cheers matey, sounds easy enough.

Any more sugestions as to what could be causing the problem????

Sean..
 

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Have to say though, that an air leak is the prime culprit. When you pressurise the intake system with positive boost you're losing some of the air meaning your car can't hold 1 bar - it's eeking down to 10psi. Similary an intake leak can produce high idle and rough running, as unmetered air is getting into the engine.

Similarly, it sounds like it may also be something that is brought on by heat - possibly expansion of something or other.

You can spray round all the joins in the intake piping with carb cleaner to see if the running engine draws any in and you'll then hear the idle rise momentarily (the prime place to check this is around the intake plenum/throttle plates - this is where you'll get an air leak if an intake gasket's gone). Alternatively, you can remove the intake piping from the air filter up to the entry pipes for your turbos, buy a couple of pipe caps and jubilee clips and tap in an air valve into one of them. Use the caps & jubilee clips to seal off the turbo entry pipes and then use a pump to pressurise the whole intake system via the air valve you've tapped into one of those caps. 20psi should do it and if your environment is quiet enough you should be able to hear any leaks, thus allowing you to track 'em down.

Have you got an atmospheric dump valve fitted? Another possibility is that it may be leaking (quite common)...
 
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