General: - v70 2.4t 51reg awd boost intemitent - Page 3

jameshaw · Jan 26th, 2011, 21:28

yeh its next on the list

jameshaw · Jan 27th, 2011, 16:37

right,tested waistgate,it is ok,put boost gauge inbetween tcv and waistgate and nothing even all the way up the rev range,so either the tcv is not working,i have swaped it for working one,so what tells the tcv to open,it must be the atmospheric boost sensor in the intercooler pipwork? does anyone know what the resistance of the tcv and boost sensor?

princepugh · Jan 27th, 2011, 19:42

Hrmm, interesting - the MAP sensor will supply a reading to the ECU (along with other sensory inputs) in order that it can determine the TCV duty cycle so it's certainly a suspect but would have thought it might throw a code?

Can't comment on resistance I'm afraid but you could see if a member is prepared to hook a VCT2000 up so you can get manifold pressure readings?

You might also want to consider routing the TCV hose which comes off the compressor (red), direct to the wastegate nipple, this is a 'safe' routing so you'd expect to see low, safe boost as the more the turbo spools, the more pressure goes directly to the wastegate. If you don't see safe boost in this configuration, you know you've not got sufficient pressure from the compressor hose, if that makes sense? Unlikely I'd have thought but it might be worth a try just to eliminate?

jameshaw · Jan 27th, 2011, 20:03

yeh ive got a manual boost controler hooked up set on low boost so it drives ok and is working as a turbo car should iam running 6-7psi ish and it drives as it should ,i am tempted to get a map sensor they are about 60 quid,not alot else it can be

princepugh · Jan 27th, 2011, 21:02

The MAP sensor is fairly easy to get out - you could give it a visual inspection and a soaking in electrical cleaner. Still think you should hook up some diags which will show you manifold pressure before you shell out.

jameshaw · Jan 27th, 2011, 21:21

yeh could do with live run data

deathrider311271 · Jan 27th, 2011, 21:24

just read this post and as far as im aware your car should only be running 6-7 psi anyway, it should not have been running 14 psi, a standard T5 only runs 12psi, so i wouls suspect the ECU is cutting the boost back and chucking a load more fuel in to try and compensate

jameshaw · Jan 28th, 2011, 11:01

thats what makes me think its the map,because whatever tels the tcv to open the waistgate isnt..so it must be a boost sensor(map)

Jan 26th, 2011, 21:28	#21
jameshaw New Member Last Online: Mar 28th, 2011 21:07 Join Date: Dec 2010 Location: bournemouth	yeh its next on the list

Jan 27th, 2011, 16:37	#22
jameshaw New Member Last Online: Mar 28th, 2011 21:07 Join Date: Dec 2010 Location: bournemouth	right,tested waistgate,it is ok,put boost gauge inbetween tcv and waistgate and nothing even all the way up the rev range,so either the tcv is not working,i have swaped it for working one,so what tells the tcv to open,it must be the atmospheric boost sensor in the intercooler pipwork? does anyone know what the resistance of the tcv and boost sensor?

Jan 27th, 2011, 19:42	#23
princepugh Senior Member Last Online: May 29th, 2013 23:24 Join Date: Jul 2010 Location: Sheffield	Hrmm, interesting - the MAP sensor will supply a reading to the ECU (along with other sensory inputs) in order that it can determine the TCV duty cycle so it's certainly a suspect but would have thought it might throw a code? Can't comment on resistance I'm afraid but you could see if a member is prepared to hook a VCT2000 up so you can get manifold pressure readings? You might also want to consider routing the TCV hose which comes off the compressor (red), direct to the wastegate nipple, this is a 'safe' routing so you'd expect to see low, safe boost as the more the turbo spools, the more pressure goes directly to the wastegate. If you don't see safe boost in this configuration, you know you've not got sufficient pressure from the compressor hose, if that makes sense? Unlikely I'd have thought but it might be worth a try just to eliminate?

Jan 27th, 2011, 20:03	#24
jameshaw New Member Last Online: Mar 28th, 2011 21:07 Join Date: Dec 2010 Location: bournemouth	yeh ive got a manual boost controler hooked up set on low boost so it drives ok and is working as a turbo car should iam running 6-7psi ish and it drives as it should ,i am tempted to get a map sensor they are about 60 quid,not alot else it can be

Jan 27th, 2011, 21:02	#25
princepugh Senior Member Last Online: May 29th, 2013 23:24 Join Date: Jul 2010 Location: Sheffield	The MAP sensor is fairly easy to get out - you could give it a visual inspection and a soaking in electrical cleaner. Still think you should hook up some diags which will show you manifold pressure before you shell out.

Jan 27th, 2011, 21:21	#26
jameshaw New Member Last Online: Mar 28th, 2011 21:07 Join Date: Dec 2010 Location: bournemouth	yeh could do with live run data

Jan 27th, 2011, 21:24	#27
deathrider311271 I've Been Banned Last Online: Jun 21st, 2022 19:26 Join Date: Mar 2010 Location: Grimsby	just read this post and as far as im aware your car should only be running 6-7 psi anyway, it should not have been running 14 psi, a standard T5 only runs 12psi, so i wouls suspect the ECU is cutting the boost back and chucking a load more fuel in to try and compensate

Jan 28th, 2011, 11:01	#28
jameshaw New Member Last Online: Mar 28th, 2011 21:07 Join Date: Dec 2010 Location: bournemouth	thats what makes me think its the map,because whatever tels the tcv to open the waistgate isnt..so it must be a boost sensor(map)

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)