Overboosting!!!! oh no!!!

[antgtir]

Recently i have had a bit of a problem with the R i.e. it wasn't ideling correctly etc and it started to kindof miss at heavy loads. As a result of this i changed the leds plugs rotor arm and dizzy for new Nissan ones, this solved the problem, or so i thought.

When i had fitted the parts i tried it out on the road and it ran like a dream, it was picking up really well and felt alot faster than it has ever felt. However i then looked at the boost gauge (standard) and the needle was nearly bursting out of the gauge, on full throttle the needle hits the right hand side of the gauge which it has never done before :? Before the probs it used to sit just shy of the +7 markwhich is about right but now it shoots way past that, the turbo screams and the induction (standard box etc) can be heard very prominantly.

So from what ive done something has changed but just changing the leads and plugs etc surly cant change the boost on the turbo can it????

How do i get the turbo to boost how it used to and what could be the prob now??

Help would be most defo appreciated on this one, thanks alot,

Ant. :?

 

[Mr GTiR]

Sounds like either the standard actulator or boost solanoide has failed. There really the only two things that control stock boost.

Check that none of the pipes have come off or have a split in them.

 

[antgtir]

Sounds like either the standard actulator or boost solanoide has failed. There really the only two things that control stock boost.

Check that none of the pipes have come off or have a split in them.

Thanks mate, do you know what checks i can carry out to diagnose which of the two poss sources it could be??

I thought if a pipe was to come off then the power would drop off rather than increase :?

Is the car still ok for driving as long as i dont stick my foot down??

cheers, Ant.

 

[kyepan]

I thought if a pipe was to come off then the power would drop off rather than increase :?

Is the car still ok for driving as long as i dont stick my foot down??

as long as its not boosting it is fine, too much boost (air), not enough fuel = lean mixutre, too much heat, pre detonation of fuel in the chamber and piston damage. engine rebuild.. argh.

The pressure in the hose coming from the intercooler is sensed by the boost solonoid, which in turn opens the actuator to vent the excess boost when it gets to a certain level to keep it at a controlled level. So a pipe coming off will stop the pressure rising, tripping the solonoid, activating the acutator.. causing you to run unlimited boost.. a very bad thing.

feel underneath the right hand side of the intercooler there is a little pipe there, and another under the back.. or at the top at the back.. check they both have their hoses.

 

[antgtir]

Cheers for that Kyepan, i shall have a quick look now im on my dinner. I take it that if any one of these pipes is off it would cause the probs im experiencing now??

Ant

 

[antgtir]

feel underneath the right hand side of the intercooler there is a little pipe there, and another under the back.. or at the top at the back.. check they both have their hoses.

Right on the button, nice one mate, just looked at the bits mentioned and the pipe at the back of the intercooler was off, that will teach me to do the jobs in the dark

Thanks to all for their help hopefully this will be the cause of the prob which will now be sorted, smiles all round for me lol :lol: :lol:

Cheers, Ant.

 

[kyepan]

8) ur welcome matey

 

[smcnairn]

I also have an overboosting problem i first thought it was the actuator which i have now changed for an uprated one and checked all pipes are in good nick. could my boost solinoid be goosed and would this cause over boosting????. Its getting annoying now its been like this for months now!! :?