fuel air hose

[tom's dad]

Having today taken out the old wrinkly air ducts through to the plenum and replaced the filter I took the car for a spin. being a 4.3 it has always sounded good, but now it sounds as though it is on nitrous or something ! and crackly on acceleration.
The old tubing had collapsed and was probably only 50% effective. It runs and accelerates much better than it has been recently.

Why the sound/noise difference?
Could it be running too weak? And other questions.

[T1pper]

I have just brought some new induction hoses for my Griff 500 as the old ones are looking a bit tired, I will report on any difference.
I will be fitting them at the weekend.

[rigga]

T1pper said:

I have just brought some new induction hoses for my Griff 500 as the old ones are looking a bit tired, I will report on any difference.
I will be fitting them at the weekend.

Which type and from where?

[T1pper]

ACT performance parts

If you google them they have a whole range for the Griff and they are on ebay as well, I also got a silicone coolant set complete with the stainless tubing.

They look good, will fit them up at the weekend.

[blitzracing]

Having a collapsed inlet hose does horrible things to the fueling. When the throttle is wide open the inlet manifold should be near atmospheric pressure. The fuel regulator measures this, and raises the fuel pressure so the correct amount of fuel is supplied by the injectors / ECU for the RPM and AFM readings (or engine load). If the inlet pipe collapses the inlet vacuum remains higher- even when the throttle is fully open so the fuel pressure is held lower than it should be. The AFM flow will be lower also, but the throttle pot will say the throttle is wide open and the combined effect is outside the ECUS's normal range of parameters, so it throws a fault code, (possibly based on lean lambda readings) - In the example I came across it constantly flagged low fuel pressure, which is completely wrong. The car will also not run well under load as the air is being restricted. Had us foxed for some time as we were looking for the wrong fault.

[T1pper]

rigga said:

T1pper said:

I have just brought some new induction hoses for my Griff 500 as the old ones are looking a bit tired, I will report on any difference.
I will be fitting them at the weekend.

I finished up fitting the induction hoses last weekend, the long one from the air filter to the AFM was worn through to holes on the underside where it could not be seen so air was being sucked in after the filter. Also the flat panel air filter was filthy! I felt happy to have found something and not just an engine bay tidy up.

At the same time I fitted a new Bosch coil, magnecor leads, spark plug extensions, new air filter, Lucas rotor arm and a set of standard NGK plugs.

The car now sounds really punchy and responsive and I am noticing a smoother pull at lower revs.

Before the engine would start hot or cold with no problems and not a missfire in sight but the improvement was vast, just by swapping out old components even though working gave a noticable improvement.

Lastly the ACT hoses fitted well and looked good but there was no detectable difference in the sound of the engine