I just purchased an 89 Honda CRX, DX model with A/T and 155K on the OD. When driving at a constant speed the engine surges. It will rev up 250-300 RPM for a few seconds and then back to normal, then up, then down. This will continue and eventually the CEL will illuminate which will stop the surging but it then seems to drive at the higher RPM and my MPG's go in the dumps. Although the RPMs raise when it surges it does not change the vehicle speed. Also once the CEL illuminates it raises my idle speed from 750 to approx 1200 when it is in park.

I Figure that I should be getting a MINIMUM of 35MPG. 2 fill-ups ago was 33.1MPG and last fill-up was 28.5MPG.

When I shut off the car and start it back up it the CEL will be off and then the surging will start. It only happens when you are at any constant speed be it 40 or 75. The CEL may take 1 or 2 miles to illuminate or it may drive for 20 or more miles before it comes on.

I checked the ECU (OBD0) and the LED is flashing code 17 which is the VSS. Could a bad VSS cause the issues that I am having?

What other items should I check? The igniter? The coil?

Lastly, I went to Autozone and they did not realize until they looked in their test book that they could in fact check an igniter. If the igniter has an intermittent problem will it test bad at Autozone?

Thanx in advance for any help you can give me...