Not building full boost
08-16-2019 | 06:57 PM
#1
Thread Starter
Burning Brakes
Joined: Jul 2013
Posts: 789
Likes: 11
From: Lafayette Louisiana
Not building full boost
So it appears I cannot build full boos in my 86 951. I used to be able to get to 2 bar. But now I’m only getting to about 1.7 so it appears I cannot build for boost
it has a Vitesse (<sp?) chip.
I have a Lindsay racing wastegate as well and I cannot find any vacuum leaks. All my vacuum hoses appear to be plugged in and in good shape.
The boost build all the way up to 1.7 and then just stops and holds. I’m not sure what the most efficient way to check this is.
I have a smoke machine can I use this to check for exhaust leaks but where would be the best place to plug it in. Also is there a way to use the smoke machine to check for exhaust leaks in the exhaust system.
What is the easiest way to check the turbo to see if it’s worn out. It’s not blowing smoke or anything else.
it has a Vitesse (<sp?) chip.
I have a Lindsay racing wastegate as well and I cannot find any vacuum leaks. All my vacuum hoses appear to be plugged in and in good shape.
The boost build all the way up to 1.7 and then just stops and holds. I’m not sure what the most efficient way to check this is.
I have a smoke machine can I use this to check for exhaust leaks but where would be the best place to plug it in. Also is there a way to use the smoke machine to check for exhaust leaks in the exhaust system.
What is the easiest way to check the turbo to see if it’s worn out. It’s not blowing smoke or anything else.
08-16-2019 | 07:55 PM
#2
Three Wheelin'
Joined: Jun 2010
Posts: 1,736
Likes: 36
From: Northern California, '86 951
You can check the turbo by disconnecting the hose at the banjo bolt. You can just untwist the banjo bolt, remove the eye bolt, and replace the banjo bolt. The hose leads to the cycling valve and is necessary for the computer to make vital determinations, so you should use this method very sparingly (ie once). Leave the banjo bolt in because it will help cap boost pressure. It might go up to 16 psi but the engine will not have an ideal air/fuel ratio form what I understand.
You could plug the smoke machine into the vacuum hose at the brake booster, ie the one that runs from the booster toward the passenger side and then under the intake manifold. Needless to say, you cannot drive with the booster unplugged like this.
How are you sure there is no vacuum/boost leak? There are so many hoses that can't be seen. I just fixed a boost limit like the one you described. I made a thread. The hose from the control line/cycling valve to the J boot was busted. Replaced it and all is well.
Good luck
You could plug the smoke machine into the vacuum hose at the brake booster, ie the one that runs from the booster toward the passenger side and then under the intake manifold. Needless to say, you cannot drive with the booster unplugged like this.
How are you sure there is no vacuum/boost leak? There are so many hoses that can't be seen. I just fixed a boost limit like the one you described. I made a thread. The hose from the control line/cycling valve to the J boot was busted. Replaced it and all is well.
Good luck
08-16-2019 | 11:13 PM
#3
Thread Starter
Burning Brakes
Joined: Jul 2013
Posts: 789
Likes: 11
From: Lafayette Louisiana
@bonus12
speaking of banjo bolts, I just checked the vacuum hose going to that fitting and lo and behold the hose was cracked through. Cut the bad part off and reattached and car is back to normal!
I like these types of fixes
speaking of banjo bolts, I just checked the vacuum hose going to that fitting and lo and behold the hose was cracked through. Cut the bad part off and reattached and car is back to normal!
I like these types of fixes