less boost after wastegate adjustment Topic is solved

[j-john20]

thanks in advance for helping, i have a 1998 s70 glt, i attempted to adjust the wastegate back to stock as it was "tweaked" per previous owner-so instead of applying pressure i applied vacuum to the wategate and adjusted it completly rong-broke tcv vacuum lines in the process-drove it home with broken vacuum lines- properly adjusted wastegate per turbo 102 video and chart at 1.8 psi-replacedtcv with ipd unit and vacuum hose kit- boost is at 5 psi now and has no power - before i couldnt keep traction off the line and had no turbo lag-great power and LOVED the car, now ive spent more money and it is not the same car at all i dont have anything else to try and am so confused i did have it diagnosed by volvo dealer and was told to replace the tcv so any help is so greatly appreciated . i now know that the rod being shortend within reason will not hurt it and i wish i had left it alone, also the car was holding 10 psi and now at 5 and i have tried adding a couple of psi to the 1.8 wastegate setting and still nothing,the wastegate line off i can get close to 10 psi but it does have turbo lag and not as much power as before and obviously cant keep driving without the hose thanks again for the help,

[JDS60R]

put the stock TCV back in

[j-john20]

sure ill give it a try, i adjusted the wastegate before i replaced it. the only difference is the vacuum hoses are replaced now,also is the ipd unit not suffiecient just curious ill try to return it if not or is this just for diagnosing purposes because i was told it was bad from the volvo tech thanks again for the reply.

[j-john20]

i tried the stock tcv problem still persists any other suggestions. thanks.

[jblackburn]

The IPD unit needs to be "taught".

You should have got instructions with it, but as I recall, you need to hold the car at half-boost for 10 seconds at a time, let up, and then go at it again 4 times. It's been so long since I did that, you should not trust me to remember that off the top of my head and find the instructions though.

[JDS60R]

Ok - assuming that the original TCV worked fine before replacement and both TCV have produced a bad result we can move forward.

I need you to perform some checks and adjustments.

1.Check the routing of the TCV hoses to make sure they are correct ( many have made this mistake thinking they were sure they had it correct.) Get the diagram and check them to remove it from the diagnostic list. Check for any hidden leaks and pressure bleed of devices. I usually use a pressure pump to assure the wastegate is working correctly.

2. Reset the wastegate to just below the pressure threshold. you will need a pressure pump or supply to do this. Some have mistakingly thought the spec to be vacuum -it is not- it is pressure. ( I believe you know its pressure but I think you threw in an extra turn and we don't need that variable right now)

3. Check all of the turbo hoses for a good seal and connection

4. Reset the computer and then drive it for a few hours with the good original TCV in place and the wastegate set per Volvo spec.

Let us know the result including any different noises you may be hearing.

[j-john20]

ok ill give that a try and let you know, yellow to wastegate, red to turbo and blue to intake hose is how the routing reads also when you say below pressure threshold do you mean just less than 1.8 psi as that is what is factory by ipds chart thank you so much

[JDS60R]

let me know your engine you have and what your tcv looks like (round or square) . I will get you the spec from volvo

[j-john20]

also jblackburn thanks for the input. i did teach it per the instructions and still the same result, thanks.

[JDS60R]

Volvo instructions are in Kpa
1kpa = 0.1450377psi

12.5 kpa = 1.812972 psi

15 kpa = 2.175566 psi

18 kpa = 2.610679 psi

30 kpa = 4.351132 psi