My automatic 1994 940 starts very rough--it's idling around 500, and when the engine first starts it will not accelerate above an idle speed. I can push the accelerator to the ground with no response. Sometimes leaving it in park and revving the engine gets it going, sometimes I just need to wait a couple of minutes. It's a new-to-me car, so I don't know if this is a new problem or not, but it's July, so I know it's not related to outside temperature.

Definitely follow the good advice given above! Get the car up to a baseline.

Any codes?

If it were my car, I'd start with the easy stuff - look for an air leak. Once found usually a pretty easy fix. Check the air intake hose, look for damage, splits etc. Check all air hoses and vacuum lines. If nothing there, I'd next move on to the idle air control valve. Give it a good cleaning!

No codes. I will definitely check for an air leak and give it a good cleaning as suggested by others.
Thank you!

Dear MorganM,

Hope you're well. Further to j.pelchat's excellent points, I suggest use of an aerosol electrical contact cleaner (e.g., DeOxit or similar). The reasons: (a) an invisibly-thin layer of corrosion can disrupt a circuit (things can look fine, but aren't); (b) it is very hard to clean the contacts inside connectors with steel wool or fine sandpaper, but a spray will reach and clean those.

On connectors in the engine bay (or other exterior areas) a thin coating of di-electric (tune-up) grease on the connectors' metal contacts will keep humidity away from cleaned contacts and so slow renewed corrosion.

If You've not done so, replace all working fluids (coolant, oil, brake fluid, automatic transmission fluid and differential oil). This site's FAQs (upper left) provide guidance as to the doing of these things.

Hope this helps.

Yours faithfully,

Spook

As the car is new to you, you should begin by doing a good deal of maintenance. You will find a lot of advice here on that. Remove, inspect and clean all air intake. Inspect all vacuum lines. clean idle air control valve. Change fuel filter. Clean and treat grounds and electrical connections. Any one of these things and more may help, but you want to get the car to a good base level of maintenance so going forward you will know what you don't need to do
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89 240 wagon, 94 940, 215K, 94 940, 141K