|
S80 '98-'06 / S60 '00-'09 / V70 & XC70 '00-'07 General Forum for the P2-platform S60 / V70 / XC70 / S80 models |
Information |
|
over boost issuesViews : 465 Replies : 7Users Viewing This Thread : |
|
Thread Tools | Display Modes |
May 17th, 2024, 09:13 | #1 |
Premier Member
Last Online: Jun 17th, 2024 22:07
Join Date: Nov 2007
Location: Letchworth
|
over boost issues
v70 t5 2006. I've had over boost issues for a while, I've replaced tcv, map, maf, intercooler, all vacuum pipes and a new actuator.
but still have over boost, yet if I boot the car and the boost goes to 2bar its fine, the moment I hold it at 0.5bar it over boosts. any ideas people. I fone a smoke test yesterday and there is no air leaks on any of the pipe work. |
May 17th, 2024, 16:18 | #2 |
Premier Member
Last Online: Today 10:51
Join Date: Aug 2013
Location: Emsworth,hants
|
Hi , what tools have you got, have you got vida,
with the ignition on but with the engine not running, look at the MAP reading VS the ECM Atmosphere sensor it should be the same, The 2 bar you take the boost to ,is this including the atmos psi, is the car re-mapped for this psi, when you changed all of these sensors , are they all original, or cheaper ones, look at wiring for any damage, at/from sensors test that all sensors are working as they should, is the TCV actuator working correctly, i fitted a new one, cheap from china that worked very well, but then parked the car up for some time (a few weeks) and when i went to use it , i had no boost control, and i could only get a small bit of boost at higher revs, i tested the TCV actuator and it was not moving, it was stuck at no boost, it could had been the other way, so i fitted a original one, and all is ok, can you pressurise the intake and read the MAP Pressure is reading the same, Thanks and good luck, Dave |
May 17th, 2024, 18:03 | #3 |
Premier Member
Last Online: Jun 17th, 2024 22:07
Join Date: Nov 2007
Location: Letchworth
|
all new sensors are bosch, wiring is fine, been on vida everything was fine.
it's a expolice training and mapped by frf swansea for the police, I've had the car for ten years Last edited by wise old monkey; May 17th, 2024 at 18:18. |
May 17th, 2024, 20:57 | #4 |
Member
Last Online: Jun 19th, 2024 10:53
Join Date: Sep 2021
Location: Bath
|
That's a lot of boost!
How does the car actually drive? Does the ECU throttle it back or does it just feel/ look wrong? Did it suddenly start doing this or was it progressive? It sounds like a wastegate issue. Basic checks that I suspect you've already done so apologies in advance: 1. Is it the correct Pierburg TCV? Correctly plumbed in? Are the lines good quality/ right size? 2. Is it the correct wastegate actuator? 3. Is your wastegate free to move? 4. What preload is set on the wastegate actuator? |
May 17th, 2024, 22:02 | #5 |
Premier Member
Last Online: Jun 17th, 2024 22:07
Join Date: Nov 2007
Location: Letchworth
|
1. yes
2.yes 3. yes 4. 7.5psi going to try another actuator tomorrow |
May 18th, 2024, 09:49 | #6 |
Member
Last Online: Jun 19th, 2024 10:53
Join Date: Sep 2021
Location: Bath
|
I assume the car came with the actuator set at his PSI to go with the tune and it moves correctly when pressurised (guessing you have Mitivac or similar).
You could try carefully running at the overboosting threshold with the yellow clamped off to see if it behaves the same without the TCV controlling the wastegate, ie: is the TCV actually opening it. Don't boot it, however! How's your bypass/recirc valve? |
May 18th, 2024, 13:41 | #7 |
Premier Member
Last Online: Jun 17th, 2024 22:07
Join Date: Nov 2007
Location: Letchworth
|
stripped it all down again this morning, the hose under intake on the turbo had come off, swapped the actuator out for my expensive forge motor craft actuator, now its got no over boost, but won't go over 0.5bar, so I guess I need to setup the actuator.
can not get to the recirculating valve to check it |
May 21st, 2024, 15:16 | #8 | |
New Member
Last Online: May 23rd, 2024 18:00
Join Date: May 2024
Location: Indianapolis
|
Quote:
Preload should be 3 turns on the nut then snugged down. TCV will handle the rest. |
|
The Following User Says Thank You to precisionguesswork For This Useful Post: |
Currently Active Users Viewing This Thread: 1 (0 members and 1 guests) | |
|
|