[CDirkes]

Hi Gang,

I just bought a '90 turbo convertible automatic which looks beautiful and seems to have been well maintained. It starts and runs well, but compared to the '81 8V turbo I used to own, it's a real slug. You have to FLOOR it off the line just to keep up with traffic. I suspect I'm getting zero boost and have some serious vacuum issues. I just got the car and haven't worked on one of these in years, but here's what I can tell you so far:

1. APC guage doesn't move....ever. Seems stone dead. I don't notice any hissing noise inside the cabin to indicate a line come off somewhere.

2. Turbo does seem to be spinning. If I drive with the top down I can hear a slight whine under hard accelleration.

3. Cruise control doesn't really work. Sets but then slows down.

4. Brakes seem a little heavy compared to what I remember from my old 900T(degraded vacuum boost?).

5. No noticeable cracks in vaccum lines in the engine compartment, but might be a pinhole in the metal pipe coming from the intercooler (seems to have been abraded by hose clamps on top of it moving around).

I don't expect this car to be a rocket, but it's so slow that something's got to be wrong. When running correctly, shouldn't I reasonably expect that this 16V Turbo with an automatic to offer performance similar to the 8V Turbo 5-speed I used to own?

I'd like to tear into it this weekend. Anybody got any suggestions on where to start?

Thanks in advance,

Carl

 

[900t]

1. Check hoses behind cluster

3. Check cruise wiring, vacuum lines

4. Normal.

5. Look at everything, sometimes there are cracks or stretched lines that don't "fit" right

This car should be reasonably fast.

 

[Basre]

Brake Vac booster Leakage has been known to cause base boost conditions. Whine may just be the Trans.. they can make a small noise when stomped on.
Read and DO the Bentley base boost diagnosis.. to the letter.

 

[Jezzadee]

If you haven't got a Bentley Manual you should get one. But in the meantime there's a guide to adjusting base boost here . Save it or print it out as the site will go offline again soon.

 

[trackside]

16v's are a lot smoother in their power delivery than 8v's and often feel slower - until you look at the speedo! Add to this the fact that the auto box sucks loads of initial grunt out of the car and you may be wrong in your assumptions about 16v auto vs 8v 5spd. Turbo auto's are patheticaly slow off the line - dangerously slow in my experience when you are trying to pull out into a gap in the traffic from a junction.

 

[woywitka]

abs brakes are very different from non abs, brake much harder to push. the autobox is very very slow off the line! chances are the guage is dead as if you had no working turbo is should overcome the vacuum anyways. so:
-guage dead
-turbo porb works, get going fast, non turbo auto is very slow up hills, hard to break 60km/h, how does yours do? do you feel any lift once up to speed and you floor it?

 

[900t]

Hi Gang,

I just bought a '90 turbo convertible automatic which looks beautiful and seems to have been well maintained. It starts and runs well, but compared to the '81 8V turbo I used to own, it's a real slug. You have to FLOOR it off the line just to keep up with traffic. I suspect I'm getting zero boost and have some serious vacuum issues. I just got the car and haven't worked on one of these in years, but here's what I can tell you so far:

1. APC guage doesn't move....ever. Seems stone dead. I don't notice any hissing noise inside the cabin to indicate a line come off somewhere.

2. Turbo does seem to be spinning. If I drive with the top down I can hear a slight whine under hard accelleration.

3. Cruise control doesn't really work. Sets but then slows down.

4. Brakes seem a little heavy compared to what I remember from my old 900T(degraded vacuum boost?).

5. No noticeable cracks in vaccum lines in the engine compartment, but might be a pinhole in the metal pipe coming from the intercooler (seems to have been abraded by hose clamps on top of it moving around).

I don't expect this car to be a rocket, but it's so slow that something's got to be wrong. When running correctly, shouldn't I reasonably expect that this 16V Turbo with an automatic to offer performance similar to the 8V Turbo 5-speed I used to own?

I'd like to tear into it this weekend. Anybody got any suggestions on where to start?

Thanks in advance,

Carl

Hey think about this... today I started up my 900 S 5-spd and went for a drive. I got upto 60km/h in 3rd gear, and couldn't speed up! Floored the gas and all I could get was 60km/h or so. Maybe a bit more if I had more space.

I get back, I smell brakes. The parking brake was seized! Might want to check something like that I thought me engine was blown! ;oops:

 

[dljpdx]

-turbo porb works, get going fast, non turbo auto is very slow up hills, hard to break 60km/h, how does yours do? do you feel any lift once up to speed and you floor it?

That's my experience as well - it doesn't skree off the line, nor from lower speeds, but if you're at 30/40mph+ and floor it, you definitely notice it, even moreso once you look at the speedo. I, too, thought something was amiss, but it's just the way it seems to work and feel. Don't reply on it for darting into traffic from a stand-still, but it's great for scooting around someone once up to speed.