my car

[si850r]

evenin folks......


Well i ve managed to do a little clip of my erratic tick over. Today after work I FINALLY managed to get the torx screws out of the spark plug cover and the plugs are in good nick , they are original volvo ones. I gave them a damn good clean and the motor I would say is running slightly better. There is still the misfire fire there tho, but it isnt stalling now. On tick over it is hunting for revs
(this you can see in vid) it also drives like this in traffic (which with an auto box is quite tricky) what s happening as well is in traffic i have very little brakes, but once travelling they are back to normal. I ve cleaned the idle control valve and the flap is moving freely on its own (should there be a buzzing sensation from this? clearly audible with the cover on it) and also cleaned round the throttle housing.

In the vid that is me hitting the accelerator to show what it does after that, every time the revs go up thats when you can here a misfire in the intake manifold.(thats where im guessing it come s from)

The other thing is when I take the maf off the revs drop..


And the flashing arrow has now stopped on the dash...

Heres another question,. could i do my own smoke test to check for leaks? I was thinking of holding a smoke stick (like the ones u use for detecting leaks in sours etc... by the air intake by the front grill, would this affect the workings of ant thing?

Cheers for any advice ...

http://www.youtube.com/watch?v=kc05YcdHz9Q

[claymore]

what happens if you disconnect the lead to the idle control valve?

[HADI]

plug yer seabelt in its annoying :O)

[si850r]

what happens if you disconnect the lead to the idle control valve?
i havnt tried that yet..What should happen when i disconnect it?

[Santa]

i havnt tried that yet..What should happen when i disconnect it?

I believe your revs will jump up but hold there

[si850r]

i ve just tried to disconnect it and the revs drop..

[Santa]

i ve just tried to disconnect it and the revs drop..

How low does it drop? and does it hold there?

[si850r]

i will go and do it again mate...
bear with me on this 1

[nobananas]

Hang on, you have very little brakes when in traffic ?. How do you mean that the pedal is hard or that it travels to the floor before anything happens ?. Reason being is that from what you have said (regarding the poor idle) you sound like you have an air leak, the brake servo takes it's vacuum from the inlet plenum, if there's a leak from the servo pipe or worse if the servo has gone or the seal between it and the brake master cylinder has failed you will have an air leak that could be the cause of both problems. Try disconnecting the brake servo pipe at the inlet manifold end and block off the connection and see if the idle behaves.

[si850r]

How low does it drop? and does it hold there?

right then...It stalls it...Its ticking over at about 900 but you can hear the popping of the misfire sometimes

[si850r]

Hang on, you have very little brakes when in traffic ?. How do you mean that the pedal is hard or that it travels to the floor before anything happens ?. Reason being is that from what you have said (regarding the poor idle) you sound like you have an air leak, the brake servo takes it's vacuum from the inlet plenum, if there's a leak from the servo pipe or worse if the servo has gone or the seal between it and the brake master cylinder has failed you will have an air leak that could be the cause of both problems. Try disconnecting the brake servo pipe at the inlet manifold end and block off the connection and see if the idle behaves.

the brakes are rock hard mate

[nobananas]

...oh there is also a one way valve in the servo pipe to prevent the servo being pressurised by boost, might be worth checking, mine was bleeding boost into the servo.

[si850r]

took the brake servo pipe of blocked the tube with my thumb and where its goe sonto the icv no differance in revs but didnt misfire as much put it back on and still the same?

[silverswedemachine]

Dont know whether its its big enough to affect the tick over but check the small pipe that sits on the left end of the intake manifold, chances are its perished through or come adrift, looks to me like the manifold needs to come fully off to properly check everything is in order... looks defo like an air leak though...

[nobananas]

the brakes are rock hard mate

Brakes shouldn't be rock hard. If you turn off the engine and pump the brakes a few times (to deplete the servo) then start the car with your foot on the brake, the pedal should drop slightly as the vacuum builds in the servo, if not the servo's not working.

[si850r]

Brakes shouldn't be rock hard. If you turn off the engine and pump the brakes a few times (to deplete the servo) then start the car with your foot on the brake, the pedal should drop slightly as the vacuum builds in the servo, if not the servo's not working.

right apart from the neighbours looking behind there curtains and thinking' why does he keep starting his car for?'

Tried that and on start up the pedal does drop slightly.

[si850r]

Dont know whether its its big enough to affect the tick over but check the small pipe that sits on the left end of the intake manifold, chances are its perished through or come adrift, looks to me like the manifold needs to come fully off to properly check everything is in order... looks defo like an air leak though...

I ve just changed the intake manifold gasket cause there was a leak there, had a good look round to and every thing looks good. I cant hear no air escaping either.

[si850r]

would my smoke test idea work to check for air leaks?

[nobananas]

You could block off the MAF intake pipe to the turbo then pressurise the intake system through the servo pipe and then listen for leaks. Another way is to let the vehicle idle then spray aerosol grease or similar around the intake manifold, the grease temporarily blocks the leak and the idle stabilizes OR spray carefully something like easi-start around the area, if there is a leak the easi-start will be drawn in and the engine will pick up on it for a few seconds.

[si850r]

ive tried the spray idea mate. When you block off the maf intake pipe are you on about before the maf ie in the air box?

[nobananas]

ive tried the spray idea mate. When you block off the maf intake pipe are you on about before the maf ie in the air box?

More the inlet into the turbo. I pressure tested my intercooler and pipework a few weeks ago using a plug that goes into the rubber boost pipe that comes from the top intercooler pipe. The plug has a tyre valve in it then I pressurised the system with a compressor up to about 1 bar. Leaks were really easy to hear !. The only reason I suggested the MAF side of the turbo was it also includes the turbo in the pressure test but you can go the other side (boost side) if it's easier.

[nottsgreent5]

my car did exactley the same when i took the inlet off hard breaks that didnt do much tick over was really bad and was reving on its own scary with an auto and it was all down to that little metal tab on gear box side of manifold had traped between head and manifold

[si850r]

i dont think i trapped any tho mate, I gave it a real good looking over to make sure of things like that...Its really pickling me know, I ve put up another vid of inside the engine bay when its misfiring.