The problem ive been having

[NCZ13]

here are the symptoms.

idles at 750. but every now and then, while sitting a stop light the engine "coughs". its a like a sudden thud. the rpm will dip with it. it feels like a misfire. ive searched and searched a read almost every single topic on this. one forum member said he had a similar experience witha cylinder misfire, and replaced all the coils and wires and hasnt had the problem since.

the reason im asking, is because i want to make sure its not anything else.

since ive had the cylinder 1 wire changed, i havent had a CEL.

it cant be low compression right? because low compression would be a persistent problem, and noticeable right away correct?

the first time i had this problem, i washed my engine bay, and later that night it misfired terribly. Reeked of eggy exhaust smell, sounded like lawn mower.

the second time it happened the cylinder 1 wire had was arcing the spark, and the spark wasnt getting to the plug.

now its just a slight engine thud. my cars idle isnt erratic it sits at 750, and will dip in unison when it 'coughs'

anyone have any idea what this is? should i just replace all the coils and wires?

[StealthWyvern]

Go get a can of sea foam and run it though the brake booster line. Sounds liek a Dirty EGR valve to me. Mine Would keep like it would want to stumble and die at lights every now and then tell I ran soem sea foam through it.

[NCZ13]

i was thinking about running seafoam through it just to clear up any gunk...

it doesnt seem like it wants to die tho. it just thuds, and idles normally.

[StealthWyvern]

When I say die the RPM drop below 500 and stumbles as if you almost killed a stick on take off.

[thrasher]

the stumbling & egg smell in my car was resolved by getting a new set of coils from RockAuto.

[BKJT05]

check all you vacume lines. i had this same problem after i installed my CAI and it turned out i pulled a line somewhere. i was going to put my stock airbox on and saw the line disconected, put it where it went and no more problem