The CPS is a fairly expensive piece ($140ish on Fastlane, $131 on Foreigncarpartsonline.com) so you might want to try to ovp and other associated relays which can be easily had at a junkyard.

If you are going to do the CPS though, your best bet is to get to it from underneath the car. Its held in by 1 5mm hex bolt, and its kind of a pita to get out - I ended up sending it to my mechanic to replace, because I couldn't get the thing out of its seat at the flywheel. Also, if you have good spark, then this can't be the issue, because of the way a CPS works. It shouldn't be bad if you have spark. There is an article on here in another thread that explains all about it.

The rough idle/hard start can be an expensive problem to just throw parts at, so your better off doing tests on different components to rule things out. I would guess that its not a fuel delivery problem, but there are ways to test that as well without throwing parts at the car.

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