Q: New IAC Valve - High Idling but old IAC Valve normal (800/900 rpms) 1993 Saab

asked by on

Good Day,

2 Questions please

  1. I replaced my IAC valve with a new one purchased online. However, the new IAC valve idles at 2000 - 2100 and even when it comes down it comes down much later in the day and still seems high at 1100.

But the old IAC valve starts high and comes down to around 800 - 900 rpms. This one seems fine. -------There doesn't seem to be a vacuum like anywhere.

Should I just leave the old one or have I found more problems with the car?

  1. If I have a fuel pressure regulator problem - would the "ENGINE" light come on?

additional info--Car takes 3 - 4 tries before it starts, which is why I tried putting a new IAC valve. I just installed a new MAF sensor. Still cranks after 4 tries when it's cold.. I think it's the FPR.

Thx a bunch... Shafi
My car has an automatic transmission.

Hello - I think you were on the right track with the idle air control valve. It sounds like your engine is getting extra air from an intake leak somewhere. It’s also possible there is a throttle body problem. The "multiple tries to start" problem sound like the fuel pump check valve bleeding down overnight. The fuel pump has to work extra long on first startup each day to compensate for no residual fuel rail pressure. Putting a fuel gauge on the fuel rail will confirm/reject this possibility. For diagnostic assistance, I recommend a high idle inspection performed by a mobile, professional mechanic, such as one from YourMechanic, who will come to your location, diagnose this problem, and give you an accurate assessment of damage and cost estimate for repairs.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1,000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
  1. Home
  2. Questions
  3. New IAC Valve - High Idling but old IAC Valve normal (800/900 rpms) 1993 Saab

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: Throttle position sensor - 1994 Ford F-150

Hello. The only thing to do is to verify that the TPS was installed in the correct position. Make sure you did not put the little blade on the throttle body behind instead of in front of the sensor blades....

Q: Headlights stop functioning after starting SUV

Hi there, thanks for writing in about your 2008 Saab 9-7x. The circuit protection devices are trying to warn of an issue in the system. The rest of the electronics along the lighting circuit must be inspected to prevent further...

Q: 93 buick century 6 cylinder. Overheating. Thermstat, and fluid serivice done.

Hi there. When the heater is not working and the engine overheats, it is usually due to the heater core being blocked with some sort of debris. Coolant flows through the heater core in order to charge the heater coils...

Related articles

How Do Power Car Windows Increase Passenger Safety?
Power windows are responsible for approximately 2,000 emergency room visits every year. When a power window closes, it exerts enough force to bruise or break bones, crush fingers, or restrict an airway. Though...
How Long Does a Distributor O Ring Last?
The distributor is part of the ignition system in your vehicle and its purpose is to route high voltage from the ignition coil to the spark plug. The spark plug then...
Rules of the Road For Iowa Drivers
Driving on the roads requires knowledge of the rules, many of which are based on common sense and courtesy. However, even though you know the rules in...