Throttle body problems. HELP!

[karlos1981]

Hi All,
My 2008 93 estate has been ticking over very slow and a little lumpy, so thought i would pop the throttle body off and give it a good clean. All cleaned up nice and shiny, checked the plastic gears and all good in good condition.
Installed it back on the engine and 'Disaster'!!!
It starts then goes straight into limited performance and starts misfiring horribly.
Any ideas what i may have done.

[Digger]

Hi All,
My 2008 93 estate has been ticking over very slow and a little lumpy, so thought i would pop the throttle body off and give it a good clean. All cleaned up nice and shiny, checked the plastic gears and all good in good condition.
Installed it back on the engine and 'Disaster'!!!
It starts then goes straight into limited performance and starts misfiring horribly.
Any ideas what i may have done.

Couple of questions before speculating. Did you lift the end cap to check the gears? Did you pull a battery cable when you removed the throttle body?

[karlos1981]

Hi Digger, yes i lifted the end cap and checked the gears. I removed the battery cable once it was all reinstalled. I can reset the limp mode and it will start and fast idle nicely for about 4-5 seconds before the misfire begins. Then the limited performance display lights up.

[Digger]

Hi Digger, yes i lifted the end cap and checked the gears. I removed the battery cable once it was all reinstalled. I can reset the limp mode and it will start and fast idle nicely for about 4-5 seconds before the misfire begins. Then the limited performance display lights up.

Along with he gears under that cover you have some extremely fine and sensitive contacts that rub against a position sensing disk and opening the case could have caused a fine piece of crud to move. or caused the tip of a worn contact to fall away. These things can be fixed, but you almost need a microscope to see what you are doing, so open it up again, give it a good spritz of contact cleaner and hope for the best. What you do next if that doesn't fix your problem is a coin toss, if you have free or affordable access to a Tech 2 you test before replacing, if having this work done costs as much as the part, you replace the part and hope the throttle body was the cause of your original problem.

[karlos1981]

Thanks Digger, I am about to tackle it again and see what i can do. Ill let you know how i get on later.

[karlos1981]

Body sorted! I didn't have the brass Butterfly set correctly so the motor was unable to fully close. Whoops!
Seems to run slightly smoother but tick over is still very slow (less than 500rpm), i believe this is probably the cause of the lumpy idle.

[swisssaabist]

hope you have replaced the gasket seats under the TB it could cause issues when it's done