TCV boost pressure solenoid

[aquacultureman]

Originally Posted by IainG

Hi
I have this diagram copied from the forum, if any help?
I had a feeling there are 2 down below the alternator, or in that area, it is a while since I was playing with these!!

Iain. Many thanks. Thats supurb info. Already replaced the top one and now swapping the bottom front one out now. Incidentally, I remember getting codes read some months ago for something else, and remember getting one code related to the the throttle body sensor - so perhaps one or other (or both!) of the TCVs connected to that (as per your diagram) need replacing.

Ill update this week.

[IainG]

Whilst you are delving down to the solenoids it is worth checking all the vacuum pipes and rubber elbows. I had an elbow that had split causing intermittant issues.

Vague memory. I priced up the solenoids and I believe they were about £60 each. I then was told a part number for a solenoid with all the vacuum pipework for £30
The same solenoid with all the pipes at half the price of just the solenoid!!
I will look out the numbers in case they are still cheaper.

Just found 30757740. It was £29 + VAT in 2013 !! (Solenoid and hoses)

Just re found this !!
https://www.volvoforums.org.uk/showt...errerid=116256

[aquacultureman]

Originally Posted by IainG

Whilst you are delving down to the solenoids it is worth checking all the vacuum pipes and rubber elbows. I had an elbow that had split causing intermittant issues.

Vague memory. I priced up the solenoids and I believe they were about £60 each. I then was told a part number for a solenoid with all the vacuum pipework for £30
The same solenoid with all the pipes at half the price of just the solenoid!!
I will look out the numbers in case they are still cheaper.

Just found 30757740. It was £29 + VAT in 2013 !! (Solenoid and hoses)

Just re found this !!
https://www.volvoforums.org.uk/showt...errerid=116256

Thanks Iain.
So got the bottom solenoid changed, and it appears to have sorted the issue. On your advice Im going to check the elbows when I get a chance all the same.

[aquacultureman]

Spoke too soon. I'm still getting loss of acceleration on the higher gears (5th and 6th) around 1600 rpm. Foot to the floor and nothing happens. Hopefully hooked up to Vida tomorrow although my mechanic is starting to lose the will with this. I'll update later.

[IainG]

Hi aquacultureman

Quite often you won't get any fault codes when there is a vacuum problem. Have you tried a vacuum gauge as mentioned previously, T 'd in next to the vacuum pump? You can actually have it on a long tube so you can see whilst driving. Just to see if the system is actually maintaining a vacuum?

[aquacultureman]

Originally Posted by IainG

Hi aquacultureman

Quite often you won't get any fault codes when there is a vacuum problem. Have you tried a vacuum gauge as mentioned previously, T 'd in next to the vacuum pump? You can actually have it on a long tube so you can see whilst driving. Just to see if the system is actually maintaining a vacuum?

Hi Iain. Yes, I got the tcvs and turbo vacuum tested. 2 tcvs were losing pressure, so had them replaced. However, I did a further smoke test after that, and there was also a slight leak at the base of the join between the throttle body and the intake manifold. The gasket was hard so ordered a new one from Volvo, fitted it today, and the car seems fine now. Hopefully! Multiple issues at once I guess. Will keep and eye on it.

[aquacultureman]

Originally Posted by aquacultureman

Hi Iain. Yes, I got the tcvs and turbo vacuum tested. 2 tcvs were losing pressure, so had them replaced. However, I did a further smoke test after that, and there was also a slight leak at the base of the join between the throttle body and the intake manifold. The gasket was hard so ordered a new one from Volvo, fitted it today, and the car seems fine now. Hopefully! Multiple issues at once I guess. Will keep and eye on it.

Update: I spoke to soon!!! This cars a nightmare. Now have the dreaded 'Engine system Service Required' light on and off, with temporary loss of acceleration. Running out of ideas with this. 2 x turbo control solenoids, 1 x MAP sensor, new throttle body gasket, turbo and throttle body boosters pressure tested - good pressure.
Does anybody have any ideas other that going to Volvo to get the codes properly read and diagnosed?

[IainG]

Hi
I would be very tempted to run a vacuum gauge into the car so it can be watched whilst driving (Passenger watching). Only a piece of clear pvc screenwash tube needed, t piece and vacuum gauge. Just "T" in next to the vacuum pump
I just used a basic Gunsen vacuum gauge(or loads of others on ebay)or borrow one. Just to see if the vacuum is actually there all the time whilst driving. As far as I know the car can't monitor the vacuum. It can only bring up faults with other errors indirectly.. It would be a good starting point.

[Simmy]

a short drive with vida might help diagnose the problem. do you have acess to vida or other good diagnostic tool ? did you replace the sensors with genuine parts ie pierburg .when i had similar problems i bought a cheap sensor which made the car worse to drive. so i sent back the cheap ebay one and sourced a oem pierburg one which cured my problem

[aquacultureman]

Originally Posted by Simmy

a short drive with vida might help diagnose the problem. do you have acess to vida or other good diagnostic tool ? did you replace the sensors with genuine parts ie pierburg .when i had similar problems i bought a cheap sensor which made the car worse to drive. so i sent back the cheap ebay one and sourced a oem pierburg one which cured my problem

Unfortunately dont have Vida or any Volvo scan tool. The TCVs are Pierburg replacements at least. I going to give the local Volvo dealership in Belfast a call in the morning to get it diagnosed. £95/hour last time I heard here, but they diagnosed another issue correctly last time at least.