1991 saab 900 rpm's drop down when idling, what does this mean?

order it online for around 200 and labor will be about the same, http://www.carid.com/1991-saab-900-performance-master-cylinders

Look for a test port on the fuel pressure regulator. It will look similar to the valve stem on your wheel where you add air to the tire. Connect a test gauge there..

The only thing I can this is a vacuum leak, either a hose or egr valve.

I hope this helps!

1991 SAAB 900 2.0L 1985cc L4 MFI Turbo (L) [B202L] DOHC : Electrical-Switch & Relay : Ignition Starter Switch Wiki Price STANDARD MOTOR PRODUCTS Part # US704 Intermotor
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$36.79 Add to Cart

could be EGR, Idle air control valve, is it running rough when driving or is there any white smoke out the tailpipe

sounds like you have to adjust your idle, fuel injected or carburated?

You need to change all of your wires, there may be one or two of them gone bad. "Check it at nite to see wich one is sparking fire from the wires"..

Because the car has adaptive technology, it may take a while to reset and adjust to the new, cleaner and better conditions than those to which it had previously adapted.

Did you change the cap and rotor? if the plugs needed replacement, likely they do too

Possible other causes include:

loose or corroded connections to any electrical component you disturbed (make a checklist and tick them all off as you check them);

mis-reinstallation of any F.I. part disturbed(checklist again)

obstructed water flow through the AIC valve;

improper voltage output from the AIC valve (for LH 2.4 systems, should output 8 volt at idle, dropping as load increases; for LH 2.4.2 system output 7 volt at idle etc; testing between terminals)33 and 17 at disconnected LH connector;

possible problem with MAF.

Hope this helps

Saabreur

needs to be idled down-- Connie

no it is the power steering pump. the pump is worn so at low rpm or low speeds it is real tough to steer. but when the rpm is picked up the steering gets easier.

Also check belt tension but at high rpm speeds the belt would slip and squel real loud. so i would point the problem to the power steering pump.

hope this fixs ya!!!!!!!!!!!!!!!!!!!!!!