[godwinaustin]

Hey everyone , man have I been enjoying my Aero. High speed highway driving from Wyoming to Utah to Colorado , anything from snow to mountain passes to ice to curves this car has been flying and I have been getting 35 MPG, and I’m driving her pretty hard. These 9000s are awesome freeway cars! Also once I fixed the vac leak on the boost gauge I have cruise control back. It’s hard to explain but I love the feel of these cars. I still love the C900s but they are just different beasts. On a highway trip I’d choose this 9000 almost every time I think.

On to the MAP line... So I blew the vac line off under full boost and stuttered and limped a couple miles home before finding out what the problem was. I reattached the line but it was stretched and dry rotted so I went by Napa yesterday and replaced the line. But I have since searched a bit and found that these lines need to be a specific length and diameter and material , or are supposed to be at least.

I didn’t measure the old line and the replacement line is a bit narrower in diameter. Should I order the part from Saab or just keep my existing fix? She seems to be running fine but I don’t want to have timing or mixture errors from the line being wrong and feeding the wrong pressures to the MAP sensor. Experts chime in! Thanks and hope everyone had a wonderful Thanksgiving.

 

[Doug]

Congrats on the car. Looks great!

People use either 3 mm or 4 mm internal diameter silicone vac tube so I don’t think that’s critical. Never heard of the exact length being an issue either, although one presumably cuts the new piece the same length of the old. If tube deformation under -ve or +ve pressures is in fact an issue, there must be loads of cars out there with inaccuracies going on!

I took out the original evap lines in the 2004 9-5 to replace with the post 2005 version, and thought fuel hose would be sufficient. The bit from the evap valve to the NRV near the power steering reservoir sucked itself flat. So it can be an issue.

Perished original rubber vac tubing will deform, I’m sure. What I don’t know is what the result is, because I would think that after the deformation has happened, the pressure would stabilise anyway?

Regards - Doug

 

[godwinaustin]

I used regular vacuum tubing initially , from NAPA, but have since purchased and installed the factory line ( had to order from Sweden) seemed to be running ok with the normal Napa vac line though.

 

[Ryengoth]

The MAP sensor will respond faster to pressure changes the shorter and larger the line is. The diameter will have some affect on the MAP's accuracy but only during pressure changes. Static pressure will be the same on each end of the line regardless of length and diameter. Why is it not in the surge tank? That sounds like a problematic turbo management design. My 9000 is NT so I don't have to deal with that.

 

[rawill]

Nice car. Always loved the CS shape.
Sadly mine is a CSI, not an Aero.
Mine has 370,000km, no engine work done, but needs new HG, oil leak, and timing and balance chains..

 

[KaMiKaZi_t0M]

Sharp car man! I wouldn't lose sleep over the diameter or length. Allow a bit of slack to the hose, keep in mind the engine will torque back and forth; however the MAP sensor is bolted to the strut bar which won't.