Well the misfire is Still there the SES light came on this evening and i had it checked..Still #4 cylinder misfire..I guess i will be getting another engine ordered..Lets hope this one wont be bad too lol..Thanks everyone for the help.

*I'm Still not 100% convinced its a mechanical problem* I will probably run some more tests...To be continued!

 

Have you pulled the valve covers, removed the rocker arms and checked the push rods?

To check the cam lobes, you can pull the valve springs on the #4 cylinder and another cylinder for comparison and install a light spring in its place (just to add tension, but not overcome the lifter), then run the cam through a cycle, measuring the lift with a dial indicator at the valve and comparing it to another cylinder. You could also do it at the lifter, but that would require you to either remove the intake or have a VERY long dial indicator tip.

As far as it being something other than mechanical, that is a possibility. You would need to get someone that really knows what they are doing with the appropriate full feature scan tool to monitor sensor values. A misfire would be detected by the CKP/CMP sensors as a lack of acceleration of the crank when a particular cylinder is supposed to fire.

Is this 95 a full implementation of OBD2 or is it the mix-match typically referred to as OBD1.5? Full OBD2 would have the PCM on the passenger fender underhood. OBD1.5 would have it under the dash.

 

It is OBD2 the computer is on the passenger fender..as far as "digging" deeper into the engine to actually remove or unbolt any parts i will have to check with Marshall engines because all the bolts are marked with paint and i don't want to void the warranty..If i still lived Up state NY i'm sure my problem would be solved (I'm originally from the Binghamton area)...anyways..
I may for S***s and giggles go to the dealer and get an AC Delco cap with Brass inserts just to ease my mind.

 

Started up to go to the store and got about 30 feet out of the driveway and the SES light went out and it's still out as of now, but still feel misfire at idle.I'm thinking there's an intermittent problem..gonna go drive it with scan tool hooked up.Am I overlooking something so simple and stupid? Like i said i'm not 100% it's mechanical

 

Did you change the Ignition Module/Control Unit
ACDelco $122.00 at advance auto parts. Good Luck.
Check all ground connections

 

Kyle What is a CASE relearn? and how is this done
Thanks GS

 

all the grounds have been tested and are fine
I haven't changed the ICM as i was under the impression it would give a no start condition when hot..i have a misfire at idle

The SES light has been out for the last four days and came back on while sitting in traffic..now it's off again lol

 

Hi, sorry about the mis info on the spark control module I was sleep deprived.
I believe I may have your answer, but I may be wrong. This problem is not electronic in nature. Think hard about what part of your motor gets stressed the most. Answer coming soon.

 

let me know when you think you have the answer lol

 

is it a bad piston??