When I start my car the revs shoot up to over 2k and then drop back down causing the car to stall. If I keep my foot gently on the gas I can keep the revs up and prevent the stall from happening.
Once I get into 1st and start driving the problem disappears. However if I don't do this as soon as I let my foot of the gas, the revs will drop again and cause a stall.
The car is an 03 Honda Civic which is fuel injected (I thought this could be the problem). Has anyone come across anything similar?
I had one a similar problem. The contacts of temperature sensor plug where corroded, plugging the sensor in/out several times solved the issue. I would suggest you to clean the contacts of the sensor. If that does not correct the issue: Check the resistance of the temperature sensor with a digital multimeter and report the values here.
Background: On cold start the ecu tries to correct the injection amount based on engine temperature. Should the temperature sensor report overly low temperatures values the injection amount would be too high, resulting in a high revving engine.
Does your engine have an Idle speed control valve? These are usually driven by a solenoid, they can get full of carbon causing a fully open fully closed scenario as your describing.
