> At 95,000 mile the check engine light came on the subject van. The
> > guy at the parts store read the codes and indicated cylinder 4 -
> > misfire. I proceeded to change the wires and spark plugs as it is
> > almost time for the 100K tune up. I reset the codes and the car ran
> > fine! Nice and smooth! Problem solved? I wish!!! My wife drove
> > the car about 30 miles on the highway and the light came on again. I
> > took it to the parts store and I got two codes (EGR - malfunction and
> > cylinder 4 - misfire). I inspected all the vacuum hoses to the EGR
> > valve and determined that the EGR (original equipment) must be bad.
> > So I replaced the EGR and reset the codes. I added fuel injection
> > cleaner to a full tank of gas and hoped that the problem was solved.
> > Again the thing ran really well after resetting the computer and I
> > thought the problem was solved. WRONG! My wife took it our on the
> > highway and low and behold the light is on. I have not read the
> > codes as of yet and I am wondering if anyone has any suggestions. >
> Since you tried the standard plug and wire fix I would bet the injector on
> cylinder 4 is on it's way out. The way OBD II works a misfire needs to only
> happen once for it to set a code. The injector is probably working fairly
> well but on occasion fails, setting a code. A misfire MAY cause an
> emissions code to be set also, but most emissions codes take two drive
> cycles to set. Do you know what the codes were? It's going to be a pain
> but you will most likely need to test that injector.
>
>