D5 (D5244T to 2005) - VNT & TCV test in VIDA - ECM 6805 (again!)

Newbie Tony · Jun 24th, 2022, 20:12

Hi again guys!

You've maybe seen my recent post resulting in a successful replacement of my servo unit following fault code ECM 6805. All was well for a few days but driving along with the window open a couple of days ago I heard what sounded like a hose or connection blowing off and the "engine service required"/ ECM 6805 re-appeared driving to the shops.

https://www.volvoforums.org.uk/showthread.php?t=132443

I've been working my way through this thread above which is really useful though sadly the pics are no longer available. Is it possible to get them again? Just for info, the output from the vac pump is good, as are the hoses between vac pump, turbo control valve and the engine pads. I bought a new TCV recently as the response from the TCV output was sluggish on the vacuum tester gauge and I suspected this was faulty. The new one is behaving just the same though. I'd like to test the VNT governor using VIDA but cant find where the test process is. Can anyone help please? I have a 2003 XC90 D5 by the way. Also I've had a really good look but I cannot see the vacuum actuator on the turbo, so any help with location would be much appreciated!
Cheers Tony

Newbie Tony · Jul 1st, 2022, 07:52

Hi guys just thought I'd post an update. I've started fault tracing again and have bypassed the control valve and engine pads taking the output from the vacuum pump directly to the vnt governor. All is well. I'm puzzled because the hoses and pads are all holding pressure. I'm thinkin. I'm thinking there maybe a fault with the electrical signal to the control valve or bad connections. I can't think what else it could be??

Newbie Tony · Jul 2nd, 2022, 10:17

So...... for the first time since bypassing the control valve and engine pads, the "engine service required" message popped up. I pulled over, switched off and restarted and everything was fine again. I obviously have something else on the edge of breaking down. More investigation necessary! :-)

SnineT · Jul 4th, 2022, 19:08

Check any rubber hoses on the induction side of things especially turbo related, they will need a rub of a finger to detect splits but the giveaway will be oil residue where there should be none.

Newbie Tony · Jul 5th, 2022, 07:42

Thanks SnineT. Both hoses from the intercooler feel quite soft but not apparently leaking. Some months ago when I started having the ECM 6805 code I found the rubber elbow into the VNT governor was perished. I did a repair with some fuel hose and when I inspected that again yesterday the hose came away in my hand. I temporarily used a smaller diameter hose and the car went well. I've just bought the proper elbow from Volvo so am hoping they will solve my issue. I'll keep you posted. I might replace those intercooler hoses anyway......but one thing at a time for the sake of diagnosis!

Newbie Tony · Jul 6th, 2022, 07:14

Morning all! So yesterday I fitted a new elbow on the input to the VNT governor and I also fitted a new one on the output nipple of the vacuum pump as they're the same. Performance of the car was strong on a test drive after so hopefully that's it sorted. It's maybe worth noting all the bits I've replaced which have thrown up the ECM 6805 code:
1. Unblocked the VNT governor
2. Replaced the two rubber elbows
3. Replaced the front engine pad
4. Replaced the brake servo unit
5. Replaced the rubber connector on the input of the TCV valve

I think it will be worth replacing all the hoses and connections in the vacuum circuit soon anyway.

Jun 24th, 2022, 20:12	#1
Newbie Tony Junior Member Last Online: Jan 14th, 2024 10:38 Join Date: Nov 2019 Location: Yateley	VNT & TCV test in VIDA - ECM 6805 (again!) Hi again guys! You've maybe seen my recent post resulting in a successful replacement of my servo unit following fault code ECM 6805. All was well for a few days but driving along with the window open a couple of days ago I heard what sounded like a hose or connection blowing off and the "engine service required"/ ECM 6805 re-appeared driving to the shops. https://www.volvoforums.org.uk/showthread.php?t=132443 I've been working my way through this thread above which is really useful though sadly the pics are no longer available. Is it possible to get them again? Just for info, the output from the vac pump is good, as are the hoses between vac pump, turbo control valve and the engine pads. I bought a new TCV recently as the response from the TCV output was sluggish on the vacuum tester gauge and I suspected this was faulty. The new one is behaving just the same though. I'd like to test the VNT governor using VIDA but cant find where the test process is. Can anyone help please? I have a 2003 XC90 D5 by the way. Also I've had a really good look but I cannot see the vacuum actuator on the turbo, so any help with location would be much appreciated! Cheers Tony

Jul 1st, 2022, 07:52	#2
Newbie Tony Junior Member Last Online: Jan 14th, 2024 10:38 Join Date: Nov 2019 Location: Yateley	Hi guys just thought I'd post an update. I've started fault tracing again and have bypassed the control valve and engine pads taking the output from the vacuum pump directly to the vnt governor. All is well. I'm puzzled because the hoses and pads are all holding pressure. I'm thinkin. I'm thinking there maybe a fault with the electrical signal to the control valve or bad connections. I can't think what else it could be??

Jul 2nd, 2022, 10:17	#3
Newbie Tony Junior Member Last Online: Jan 14th, 2024 10:38 Join Date: Nov 2019 Location: Yateley	So...... for the first time since bypassing the control valve and engine pads, the "engine service required" message popped up. I pulled over, switched off and restarted and everything was fine again. I obviously have something else on the edge of breaking down. More investigation necessary! :-)

Jul 4th, 2022, 19:08	#4
SnineT Extrahumanestrial Last Online: Feb 13th, 2023 19:02 Join Date: Jun 2022 Location: Budapest	Check any rubber hoses on the induction side of things especially turbo related, they will need a rub of a finger to detect splits but the giveaway will be oil residue where there should be none.

Jul 5th, 2022, 07:42	#5
Newbie Tony Junior Member Last Online: Jan 14th, 2024 10:38 Join Date: Nov 2019 Location: Yateley	Thanks SnineT. Both hoses from the intercooler feel quite soft but not apparently leaking. Some months ago when I started having the ECM 6805 code I found the rubber elbow into the VNT governor was perished. I did a repair with some fuel hose and when I inspected that again yesterday the hose came away in my hand. I temporarily used a smaller diameter hose and the car went well. I've just bought the proper elbow from Volvo so am hoping they will solve my issue. I'll keep you posted. I might replace those intercooler hoses anyway......but one thing at a time for the sake of diagnosis!

Jul 6th, 2022, 07:14	#6
Newbie Tony Junior Member Last Online: Jan 14th, 2024 10:38 Join Date: Nov 2019 Location: Yateley	Morning all! So yesterday I fitted a new elbow on the input to the VNT governor and I also fitted a new one on the output nipple of the vacuum pump as they're the same. Performance of the car was strong on a test drive after so hopefully that's it sorted. It's maybe worth noting all the bits I've replaced which have thrown up the ECM 6805 code: 1. Unblocked the VNT governor 2. Replaced the two rubber elbows 3. Replaced the front engine pad 4. Replaced the brake servo unit 5. Replaced the rubber connector on the input of the TCV valve I think it will be worth replacing all the hoses and connections in the vacuum circuit soon anyway.

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