idle and boost problems

[patto1234]

Ok I know there are many threads about idling problems and all that but I can't seem to make sense of any of it.

Yesterday when i turned my car on it idled really rough. The car was shaking heaps and i swore the car was gonna cut out. It continued throughout the day whenever i pulled up at the lights. I just bought the car off a friend and i don't think its been serviced for at least 5000km so I am assuming a general service should fix it up?? Is there something more major that could be wrong?

Added to this problem i was pushing my car today, foot the floor and it wouldnt go past 5psi!!!! This is a worry since I have the bastard tuned to 12psi. Is this connected to the idle problem or could this be something completely different? Whats wrong?

I need help!!!

[Zahos]

could be lots of things

if they are related, you might have a leak somewhere in your intake hoses.

if seperate it could be an ignition/spark issue + a boost controller issue

You should check all intake hoses/pipes, and all hoses on your plenum to see if they are loose, disconnected or cracked. This is a good place to start.

[Oosh]

if visiual inspection of the intercooler piping turns up nothing, try this: get a spray bottle full of water and a little detergent, spray it over all the hose clamps etc. give her rev and any bubbles will show there's a leak.

Hope it is something simple like a boost leak.

[ScottKing GTS-4]

Try getting some spray type Carburettor cleaner, taking off your airpod/filter and gently spray/mist the cleaner into the Air Flow Meter. Dont hold the can too close when you do it or you will destroy the A.F.M., hold the can about 10cm's away from the little grill that covers the A.F.M. you can see when you take the air filter off.

[WazR32GTSt]

when you say 5psi boost, do you have an aftermarket boost gauge, or are you talking about on the stock gauge?

becuase 5 on the stock gauge is 5 * 100mmHg which is about 9-10psi which could be close to 12psi given human error in estimation

as for the idle, i would check all connections in the engine bay especially AFM (air flow meter)

next i would check all hoses for air leaks (as stated already). it may be as simple as a loose clamp

if fails, i would try changing the spark plugs (NKG coppers part no BCPR6ES work well and cost $3-4 each). the plugs may be fouled or just stuffed.

if this doesn't work then unless you have a good knowledge of your car (which i'm guessing you dont) take it to the mechanic

good luck!

Waz.

[patto1234]

Thanks for the help guys

Yeah i have an aftermarket boost gauge so there is something wrong. Theres a hose going to the boost gauge which is on its last legs (its all held together with tape at the moment).I think its the vacuum line or something along those lines. I was thinking this could be the cause of the crappy boost?

Just gonna take it in for a thorough service..guess thats the best thing for it...

cheers for the help again