I have owned this vehicle since new. 99% of time vehicle is great. Recently I noticed that if it was warmed up and idleing it would start to miss. Notice this mainly at stop lights. Almost died this morning. I have replaced fuel filter and done all regular maintenance on schedule. Was tuned up recently, within last 6 months. Have never replaced fuel pump. Any way to test to discover problem before it dies in traffic? Thank you.
Put a fuel pressure gauge on it.
At some point when it is idling roughly, pop the hood and give the idle air control valve a good whack with the handle of a screwdriver. See if that does anything - if it does then the IAC may need to be cleaned or replaced.
Did the “tune up” include new plug wires? Or just plugs? Does it have a distributor? If so, how about the cap? If it had coil packs have those checked out.
Is the check engine light on?
It does have a distributor and it had a full tune up, plugs, wires, cap, PCV valve. Engine light has not come on yet but I was surprised it didn’t this morning. It felt like it was running on 4 cylinders and about to die. Never that bad before. I will have to sit in the driveway and hope it does it there. So far it has only happened at lights. I was going to replace the fuel filter tonight just in case.