Thread: Ses random misfire cylinder 1 and egr code

So ive had the random misfire code for cylinder 1 and a egr code as well I replaced my plig and wire for cylinder 1 and my light went off for 78 miles now lights back on... Tried impliging egr valve flashing computer and re connecting but in 11 mi es came back on..... Its coming up as a misfire code but I can tell just by the way tje cars driving its not misfiring.. Couldthe egr issue be setting the misfore code and what simple fixes can I try before I have to buy a new one..... Just bought car and need light off to pass ins... Oh ya I bot a 98 grand prix gtp supercharged

Sounds like a bad EGR. Just replaced mine not too long ago. And the misfire on cylinder 1 could be a bad coil. Maybe swap 2 of the coils around and see if the misfire shows up on another cylinder. If so, then replace that coil.

When was the last time a tuneup was done? Irridium or copper plugs for the Grand Prix's. No platinums.

So I cleaned the egr valve today and the ses light shut off... 36 miles later back on same two codes.... I know its not misfiring my car drives way better no hesitation.. Exceleration is up and since I cleaned the egr my mpg has been up.. According to dic.... Any ideas... Im gonna go to a junkyard and grab a egr valve and a new cpil pack for 1 and 4 tha junk yard near me has two of my exact cars there and if that corrects problem im gonna buy brand new ones.... Oh and im not sure when the last tune up was I just bought the car less than two weeks ago..

How many miles on it? If you don't know when a tune up was done then I would get some Autolite coppers (606's I believe for the S/C cars), some lifetime warranty wires, a fuel filter, air filter and MAF cleaner. Change plugs/wires/filters and then clean the MAF with the spray. And change the EGR out since it's shot. I'd be willing to bet it will run like a top afterwards.

And check the metal accoodian looking tube that connects the EGR to the LIM as they like to crack inbetween the ribs and leak causing issues, and is often overlooked.

A code for a misfire means that it is misfiring, you just may not be able to "feel" it. Oh, and in case you didn't know you MUST run 91+ octane gas at all times or you risk blowing up the bottom end. I'd run 93 if you can get it.

The coil packs are all the same on all 6 cylinders, which is why I said swap the pack for 1/4 with another one already on your car and see if the misfire code changes cylinders. If it does then you know its the pack. If not, then its something else.

first thing in the mornin im hetting a new egr valve and if that doesnt solve the issue Im gonna check coils... Im just not wprkin right now so a tune up isnt exactly possible but it is number one on the list of **** to get done aha

Oh also I know about the 91+ octane gas some as$ hat put regular in on me today luckily it was inly two gallons so I just got 4 more gallons to dilute it

So today I replaced my egr valve got a used one for 25 and then flashed my computer and have been drivin for about 85 miles not one trip highway and city no ses light so hopefuly I fixed problem now one other question when I accelerate I only get about half boost according to my dic