What are these 2 metal tubes looks like some sort of vac? Just bought 89 951. Owner told me only mods were some sort of chip with manual control. Any ideas about these 2 tubes with no lines attached? Where do the go? I do have a rough idle at start until car warms up about 30mins later could this be cause?




Thanks for all help.

Will
NPB, FL

Sorry for large pic but first pictur post. I am refering to the two gold metal lines with nothing on ends.

 

The previous owner might have done a venturi delete and run a straight hose from the OAS and back to the J-boot. Most people with early 951 just pull that snake nest of tubes when they do the venturi delete. If they are just open pipe ends then you have some serious vac leaks and i doubt the car would run at all. Maybe this will help you re-route your vac lines.

 

runs fine other than rough idle at start. Where did you get that diagram? Where does part 6&7 connect to can't follow diagram? Would also like to know about part 29?

 

Online PET located here

The banjo bolt (Part #7) connects to the intercooler pipe that goes from the turbo to the intercooler. The Cycling valve (Part #29) is the cars method of boost control. It has three connections. One from the intake j-boot for vacuum, another from the IC pipe for boost and the last from the wastegate. Many people choose to delete these and opt for either inline boost enchancers , manual boost controllers or electronic boost controllers .

 

The diagrams come from a program called PET available at 'various' sources including the dealer. The banjo bolt(#7) and two sealing washers (36) connect to the IC pipe between the airbox and intake manifold. Part #29 is the stock cycle valve (CV) that controls the wastegate/boost level from a DME signal and pressure input. When a manual or electronic boost controller is used the CV is bypassed. You need to find if the CV is still connected to anything and if you have an EBC or MBC already on the car. Does the car make full boost now? Do an 'advanced search' on 'venturi delete' and there's a good vac diagram to explain where all the hoses go.

 

The tube on the lft shold go to the banjo bolt on the intercooler, not a must you can re-route you're own vaccum lines, especially with a boost controller.

The line on the right should be left alone, but are you running a MAF,MAP or still have the stock rubber boot? the line on the right should go to one of those (MAF/MAP/AFM boot) and MUST be plugged there.