After reading a bit of what search found me, i felt it time to explain my issues and take a poll on where to go next. My pal Chris and I have been building up my 96 850 R wagon for the last several months, and finally installed a digital boost gauge about a month ago, and were kinda shocked at the low numbers. The car is pretty much at stock levels, solid 10psi range ( shift spikes are in the high 11s ) This was before and after some of my recent mods... heres my list:

96 850R wagon

IPD ecu ( should be in the high 15s psi- Proven 17psi in Chris 96 R)
3" True CAI ( cone filter sits below the battery tray )
MSD blaster ignition
IPD wires with new cap and rotors
3" Downpipe
Magnaflow Race cat ( ceramic substrate)
2.5" cat back with high flow "turbo style" muffler
TurboXs BOV

Here's what ive done:

Removed and inspected ALL charge pipes
Replaced all found vac leaks ( there were 2 minor ones) a quick starter fluid scan of the engine says no more..? )
Replaced both vac lines to the BCS
Replaced BCS with a junk yard one, then again one from our T5 wagon
Tightened up spring pressure on BOV ( it had a small amount of loose "play" under heavy throttle *not under load*
Hand felt tension on the wastegate actuator ( felt like decent spring, but perhaps need to replace? )

Next step IMO would be swapping the WA

Perhaps there are some more ideas out there?
I feel like ive read all the common low boost threads that a basic search could find, but i'm also noob-tastic.

Thanks super much!

-Grae

 

Did you block off the factory Bypass valve when you installed the BOV?

Did you drive it with the waste gate hose off?

Are you sure the BOV isn't the problem?

 

TurboXS BOV's are known to be a leak source. I would remove it and see what you got after that.

 

- Yes, its blocked off with a plate and a ton of rtv
- NO. Which hose should i remove and what is the procedure for this test? what is the desired effect? disable the wastegate?
-"Pretty sure" its not the bov. How would I make 100% sure? (other than a different BOV )

- Yes ive heard this. Remove and cap the bung somehow?

Thanks Tech and S70, im still new with boost. : )

 

Welcome...

Where do you have it attached to? If it is on the Upper IC pipe I would suggest getting a replacement Upper IC pipe. Erie VoVo, FCP Groton should be able to supply it to you for a decent price.

I wouldn't remove the BOV and cap the flange. Why? Because you still have a place that may leak. Buy purchasing a new or used Upper IC pipe it is a solid piece and shouldn't have any defects in it or holes. Thusly giving you the best chances for no leaks.

 

I see what you are saying, but sadly this is not my case... In waiting for an opportune aluminum welder to drop into my life, We welded a bung to a 5 inch piece of pipe, cut the upper intercooler rubber pipe that connects to the top of the intercooler( not upper IC pipe/ metal/ connects to turbo) .... sleeved it in and clamped it. I did check all of these fittings in my work the other day, But i imagine anything could evade me, seeing that im new with this, and there's really no way to put my head in the bay while under load ( save a dyno)

Just reading this fellows thread, and came across another idea, what if i adjusted my wastegate rod TOO much? Honestly, I might be about 5 turns into it.. could that create an overboost scenario?

https://volvoforums.com/forum/showth...egate+actuator

 

Any adjustment out of suggested limit on waste gate is definately going to give you overboost. Try going back few threads and check where it operates and do some hit n trial adjustment attempts until you reach a balanced setting.

 

1. Never ever mess with the wastegate, bad idea.

2. So you hooked your BOV up to the Upper IC turbo hose, fine. Get another turbo hose hook that up and check.

 

IF you adjust the rod 1 turn is the max!!

Also if you disconnect the hose to the waste gate then when you drive it you will be at Max boost. But that is only to test.

 

I messed with it today, back and forth a bit, going back tword "stock" gave me less overall boost ( far from the end of the gauge)

im a horrible person. Sorry, i messed with it.... YES on the turbo hose, easy as pie. My pal chris has a whole extra set after rip kit. ( or I can steal from the t-5 wagon)

So how much of this adjustment and need thereof is to increase the factory settings, and how much is to compensate for worn parts/ springs ect ... ?

Disconnect the hose and let it hang? or cap the nipple on the wastegate and BCS ? does it matter?

THANKS!

 

Well, I popped off the DP this morning, it looks good and clean, so no issues there, it seats up well and doesn't look bend or burned up. So now for the even better new, I disconnected to vac line to the actuator and did a ginger test drive. With a small punch my tires were spitting rubber and the needle was almost to the temp gauge. Kinda scary. Drove home with no boost....

So, next step, replace the actuator itself or do a pressure test to verify its set properly?

Sounds like its not the BCS since ive swapped that multiple times.

 

I would say you over adjusted the waste gate arm.
I would adjust it back to where the arm hole is about half way over the pin. This way you have to pull the arm just a little bit to put it back on.

 

Tech, yeah thats about where its sitting currently. Could it be possible that it was just so worn that a major tightening is needed? Or perhaps it was replaced and never adjusted properly to begin with....

Also, did a quick test of the BSC, i bybassed the BCS by just joining the 2 vac lines together and i was hitting around 5-6 lbs... flat on her face... So could a BSC be "going bad" but not totally dead? Or is it a dead or alive type of failure?

Thanks Guys! Im definitely getting somewhere.

 

I think it is just not adjusted properly.
Does it do it with Just a MBC and EBC bypassed?

Also do you know the proper way to adjust the waste gate properly?
I think I still have the instructions saved for doing it but you will need regulated air pressure to set it up correctly.

 

Here is how you need to adjust it properly.

 

SUPER HELPFUL DIAGRAMS! thumbs way up sir!


MBC: manual boost controller......?
EBC: electronic boost controller...?

I think I get what you are asking... Will it boost to the desired levels with a manual boost controller in place of the stock "EBC".... is that what you mean?

If so, I don't have an answer, since i've not run it with an MBC yet. If i did, how would i bypass the EBC? where is it located ect?... Sorry super noob questions.

 

When you hook up a MBC you take the hose from the compressor side and waste gate and put the MBC in between those 2 hoses.
Leave the EBC plugged in electronically so it will not throw a code. Pull the other hose from the EBC off of the induction hose and put a cap on the induction hose so there is no vacuum leaks and all will be good.

 

Oh ok, so by EBC you are meaning the BCS? The one test I did do with this, was ran the compressor side straight to the actuator side, bypassing the BCS completely, but I had no MBC involved. When I did this, it was boosting about midway up the white part on the stock gauge, and no further. ( lets call this 5 pounds of boost) This should have given me the bone stock value that the turbo puts out correct? which im told should be about 8 lbs?

Is there a missing link somewhere in these numbers? perhaps the turbo is not outputing the proper pressure?

In related news, ive been fiddling with the WGA arm in the mean time and it seems im gaining boost as I tighten it. I got this statement from another forum member:

"My stock R was running 10 psi 9.5 turns later it's at 15 psi. Volvo quality control sucks."

Leading us back the though that id could have just been grossly mis-adjusted.

 

My Yellow R was only boosting 7 PSI stock.

The way the system works is less pressure to the waste gate the more boost. That's why when the hose was off all the way you had MAX boost.

All if the cars are different with the start boost level. Mine should have been atleast 10PSI stock and was only 7. Thats why I went with the chipped ECU and MBC. Now I am boosting 14 PSI.

If you have an ECU install a MBC and set to the boost level you want and go.

But get the waste gate arm adjusted properly and you will be good.

About that comment from the other forum He did not know anything about what he was doing. You really are not supposed to adjust it at all. But I usually go 1 turn and that's all. That makes the boost come on a little smoother and that's all.

Going more than that can cause damage and mess things up.

 

So, i thought having a flashed ecu was supposed to compensate for all of the settings... Making an MBC defunct in the system... Can you expound on this topic?

RE, the waste gate adjustment, is this a tool i can make rather easily, or do they have them as a kit? where should i be shopping for this ?

thanks!

-grae