I have a 1994 5.8L EFI and it tends to surge in neutral after being run for a while. It doesn't do it all the time though. I've changed the fuel filter/water separator and all the necessary tuneup parts. Also, after running for a while it can be hard to start. Lots of turning over but it eventually starts. It doesn't do this when it's cold though. Could I have a fuel pump problem? Are these issues related? Thanks in advance for any info!