On my 94 2.0l the idle will jump up to 2000 rpm for a second and them back down to 400 rpm and levels at 900. it does this on occasion and not every day. It shows no code and is driving (pardon the pun) me crazy. I have taken it to part stores and no codes. Has anybody experienced this problem? I don't want to replace a whole bunch of stuff if I don't have to. Thanks. Tony.