SwedeSpeed - Volvo Performance Forum banner
1 - 13 of 13 Posts

·
Registered
Joined
·
4,640 Posts
Discussion Starter · #1 ·
1998 V70 AWD with '02 RN Motor, T5 ECU, White Injectors, 13T Turbo, stock otherwise



So I got the car running with the RN motor a few months ago, slowly working out the bugs since then. Managed to get it on the road and through inspection last week, overall everything is going great and it's a pleasure to drive but I am having some difficulty getting the boost up to where it should be.

At first I had a bad WG actuator that wouldn't hold more than 1psi or so, replaced that along with a brand new OEM TCV and it's now peaking at 8psi and holding at 5psi.

In some of my troubleshooting I disconnected the WGA and it made about 13psi very easily before I let off. So the turbos working, no boost leaks that I can find, etc.

But then I route everything back through the TCV and it's not making the 10psi I expect with the T5 ECU.

I still need to make sure my WGA is set dead on, what should it be set too for an application like this?

Has anybody else had problems using the TCV and had to go to a manual controller? I would think the TCV should have no problem at this boos level but I am getting a bit flustered.

I appreciate any and all help with this matter, let me know if you need more info or what I should be testing.

Thanks very much guys!

Have a good day,
NJGB
 

·
Registered
Joined
·
4,640 Posts
Discussion Starter · #2 ·
Figured I'd update here.

Yesterday I spent a few hours trying to get this boost problem fixed and made some progress but not quite there yet.

I made a boost leak tester out of a metal cylinder, hose coupler, de-coredtire stem and compressor. This fit right onto the turbo inlet.

First found a big leak on the bottom of the intercooler, the weep hole. I hear this is supposed to let water drain out of the intercooler but mine was blown wide open and dumping tons of air, almost as fast as my compressor could fill the pipes it would rush out of the weep hole. Maybe mine has been tampered with or blown out, I don't know but I plugged it.

Found the two big leaks around the IAC valve( I think that's what it is, by the throttle body). Found a vac line that had a bad check valve and fixed it.

When I started to test for leaks I couldn't seem to pressurize the system more than 1 psi, weird it seemed to me as the car had built 13psi with the WG unhooked. I guess the turbo can generate a lot more CFM than my compressor and was able to overcome the leaks.

By the end of my boost leak testing I still could only get the system to hold about 6psi before it would drain out in a few seconds. I kinda thought I'd be able to hold more psi in the pipes during the test...



So then I out it back together, set up with the wastegate running directly off of the compressor line and went for a drive. It held a perfectly steady 4 psi.

Went ahead and re-plumbed the TCV and went for another drive. Now it makes 10psi at first but settles to about 7psi at WOT.

I swapped in my GLT ECU just to see what happened and it only makes 5psi. Back to the T5 ECU and I have spikes of 10psi settling to 7 or 8 psi and holding.

Seems to me that I am still missing a few psi. And fyi I have seem the same CEL twice now for Bank 1 System too rich, that seems to go along with the missing boost pressure.

I am a bit tired of this problem and could really use some help, either in advice or someone lending a hand to actually help me fix this. I just want my new wagon to run the way it should. Ugg.


Sorry for the rambling post but I need some input.

Thanks in advance.
 

·
Registered
Joined
·
4,640 Posts
Discussion Starter · #3 ·
I'd rather not just use a MBC as a band aid, especially if it's not running 100%.
 

·
Registered
Joined
·
305 Posts
what exhaust? clogged cat can prevent proper boost production

Sent from my rooted, rommed Galaxy Nexus....
 

·
Registered
Joined
·
4,640 Posts
Discussion Starter · #5 · (Edited)
Stock crappy "S" downpipe that was soaked in oil and coolant from old engines headgasket failure. The car would smoke when it got hot as I think the cat was soaked in oil and had to burn off over the course of 20 miles, it seems to have stopped smoking entirely by last week. It has a somewhat funny smell to the exhaust though.

That thought crossed my mind but it was able to hit 13psi with the WGA disconnect, maybe just because the turbo was spooling to the max? I guess can unbolt it from the turbo and see it it makes a difference?
 

·
Registered
Joined
·
305 Posts
you getting any oxygen sensor codes?

what is the wastegate set at?

Sent from my rooted, rommed Galaxy Nexus....
 

·
Registered
Joined
·
305 Posts
7 or 8 psi on a 10 psi tune isnt out of ordinary, especially considering some of the previous issues. A little gunk in the lines will create some pressure loss. .5 to 1 psi is about the normal drop with stock intercooler.

Sent from my rooted, rommed Galaxy Nexus....
 

·
Registered
Joined
·
4,640 Posts
Discussion Starter · #8 ·
So then I out it back together, set up with the wastegate running directly off of the compressor line and went for a drive. It held a perfectly steady 4 psi.

And fyi I have seem the same CEL twice now for Bank 1 System too rich, that seems to go along with the missing boost pressure.
I just chopped the cat out of the downpipe, going to Advanced to pick up some pipe and gonna weld in a straight pipe. I'll let you know what happens..

Thanks!
 

·
Registered
Joined
·
4,640 Posts
Discussion Starter · #9 · (Edited)
I'm a newbie welder but get seem to get by. This is where I cut it and started the straight pipe, did my best to give it a smooth transition. This section gets tucked up and bolted back to turbo after I finished welding it up.





 

·
Registered
Joined
·
305 Posts
well?

Sent from my rooted, rommed Galaxy Nexus....
 

·
Registered
Joined
·
4,640 Posts
Discussion Starter · #11 ·
haha just got back from test drive. It's better alright, seems to roll easier and hit 11-12psi when i floored it and held 8-9psi. I think it's pretty close, I know I still have a boost leak at the intake manifold gasket and injector orings. I bet if I get those leaks fixed it will hold 10psi.

:thumbup:
 

·
Registered
Joined
·
2,238 Posts
Even though I don't have any input, following this is helping me track down a similar problem. 14psi tune, but only getting 10-12 max, usually less. I'm interested in following your progress to see what helps the most.
 
1 - 13 of 13 Posts
Top