V40: - Shut-off valve

sasayu1983 · Jun 17th, 2018, 21:29

Can someone tell me when and how this valve is operated? I know that is vacuum driven by N75 valve and when I manually push it down engine stall.

Can leaking gasket on this valve don't allow me to rev over 3000 because of boost leak? There is also leakage on this junction.

gatos · Jun 18th, 2018, 09:48

As far as i know, the only purpose of this valve, is to shut off the engine when you turn the ignition off. Have you checked if the area on the valve where the air hose attaches is deformed? Sometimes, when people overtighten the jubilee clip, it deforms the valve opening to an oval shape.

Any air leak will cause some loss of power, but you should still be able to go over 3000RPM. I would be rather looking at the N75 valve, or some other component for causing the rev problem

Baffler · Jun 18th, 2018, 10:16

That looks kind of familiar

Have you tried disconnecting the MAF sensor/meter, take the car for a drive and see if it will rev past 3000rpm?

Biotoxic · Jun 18th, 2018, 18:14

If nothing else works then try to source another/check pressure regulator on the bulkhead.

sasayu1983 · Jun 18th, 2018, 21:19

@Gatos: Yes, this shut-off valve is oval in shape, but plastic hose fits well.

@Biotoxic: Boost pressure control valve is brand new - 10 days old.
There is vacuum on air filter side and turbo actuator going up and down with revs. But I can't see when shut-off valve is operated.

I think that this revving issue is clutch related because when going up hill rpm rises but speed stays nearly constant.

V40T4R · Jun 19th, 2018, 00:06

Quote:

Originally Posted by sasayu1983

@Gatos: Yes, this shut-off valve is oval in shape, but plastic hose fits well.

@Biotoxic: Boost pressure control valve is brand new - 10 days old.
There is vacuum on air filter side and turbo actuator going up and down with revs. But I can't see when shut-off valve is operated.

I think that this revving issue is clutch related because when going up hill rpm rises but speed stays nearly constant.

You might be in the presence of clutch sliping

gatos · Jun 19th, 2018, 01:24

Even if the clutch was slipping, the car should receive over 3000. Try disconnecting the MAF as Baffler has suggested. If you can also get your codes read, that could help.

Finally, it may sound silly, but have you plugged in the replacement N75 valve? If not plugged in, the ECU can't control it and therefore can't control the turbo either

sasayu1983 · Jun 19th, 2018, 07:17

N75 is plugged in. And turbo actuator going up and down with revs. Check engine is not lit.
Checked the MAF with multimeter: 2V on idle and growing up gradually with rev up.
Also checked IAT sensor (integrated in MAF): 2.14V at 20 C
MAP: 1.9V on idle and grows up with engine load.

Baffler · Jun 19th, 2018, 13:05

Quote:

Originally Posted by sasayu1983

@Gatos: Yes, this shut-off valve is oval in shape, but plastic hose fits well.

But I can't see when shut-off valve is operated.

Ok...lets just confirm something here...is the shut-off throttle closing when you switch off the engine? And fully reopening ~ 15 seconds later in preparation for the next start up?

sasayu1983 · Jun 19th, 2018, 14:03

No. It's not closing when I turn the ignition off. I'll check the vacuum hose going to shut-off valve. The hose was loose last time I checked.

Jun 17th, 2018, 21:29	#1
sasayu1983 New Member Last Online: Nov 24th, 2022 10:38 Join Date: May 2018 Location: Belgrade	Shut-off valve Can someone tell me when and how this valve is operated? I know that is vacuum driven by N75 valve and when I manually push it down engine stall. Can leaking gasket on this valve don't allow me to rev over 3000 because of boost leak? There is also leakage on this junction.

Jun 18th, 2018, 09:48	#2
gatos Premier Member Last Online: Nov 15th, 2022 21:34 Join Date: Apr 2010 Location: London / Essex	As far as i know, the only purpose of this valve, is to shut off the engine when you turn the ignition off. Have you checked if the area on the valve where the air hose attaches is deformed? Sometimes, when people overtighten the jubilee clip, it deforms the valve opening to an oval shape. Any air leak will cause some loss of power, but you should still be able to go over 3000RPM. I would be rather looking at the N75 valve, or some other component for causing the rev problem __________________ Current car: 2002 S40 1.9D, 1992 240SE Nullius in Verba

Jun 18th, 2018, 10:16	#3
Baffler Premier Member Last Online: Today 14:06 Join Date: Dec 2002 Location: Co. Limerick, Ireland	That looks kind of familiar Have you tried disconnecting the MAF sensor/meter, take the car for a drive and see if it will rev past 3000rpm? __________________ Liam... '96 854 TDI SE, '99 V70 2.5D S, '05 C70 2.0T Collection, '05 S80 2.0T SE, '15 V70 D4 SE Lux Nav.

Jun 18th, 2018, 18:14	#4
Biotoxic Master Member Last Online: Dec 30th, 2018 08:33 Join Date: Oct 2010 Location: Craigavon area	If nothing else works then try to source another/check pressure regulator on the bulkhead. __________________ Useful threads and information Guide: How to change/adjust timing belt Guide: Fitting LED's This is how S40 1.9 TD engine components looks like Information regarding EGR, problems and solutions A.K.A. Hesitation, sluggishness etc.

Jun 18th, 2018, 21:19	#5
sasayu1983 New Member Last Online: Nov 24th, 2022 10:38 Join Date: May 2018 Location: Belgrade	@Gatos: Yes, this shut-off valve is oval in shape, but plastic hose fits well. @Biotoxic: Boost pressure control valve is brand new - 10 days old. There is vacuum on air filter side and turbo actuator going up and down with revs. But I can't see when shut-off valve is operated. I think that this revving issue is clutch related because when going up hill rpm rises but speed stays nearly constant. Last edited by sasayu1983; Jun 18th, 2018 at 21:22.

Jun 19th, 2018, 01:24	#7
gatos Premier Member Last Online: Nov 15th, 2022 21:34 Join Date: Apr 2010 Location: London / Essex	Even if the clutch was slipping, the car should receive over 3000. Try disconnecting the MAF as Baffler has suggested. If you can also get your codes read, that could help. Finally, it may sound silly, but have you plugged in the replacement N75 valve? If not plugged in, the ECU can't control it and therefore can't control the turbo either __________________ Current car: 2002 S40 1.9D, 1992 240SE Nullius in Verba

Jun 19th, 2018, 07:17	#8
sasayu1983 New Member Last Online: Nov 24th, 2022 10:38 Join Date: May 2018 Location: Belgrade	N75 is plugged in. And turbo actuator going up and down with revs. Check engine is not lit. Checked the MAF with multimeter: 2V on idle and growing up gradually with rev up. Also checked IAT sensor (integrated in MAF): 2.14V at 20 C MAP: 1.9V on idle and grows up with engine load.

Jun 19th, 2018, 14:03	#10
sasayu1983 New Member Last Online: Nov 24th, 2022 10:38 Join Date: May 2018 Location: Belgrade	No. It's not closing when I turn the ignition off. I'll check the vacuum hose going to shut-off valve. The hose was loose last time I checked.

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