just picked up a 91 firebird when im in drive at a stoplight or drive thru i can feel random misfires and the tac dips slightly as its misfiring. Checked timing just now and discovered the timing mark is at the 1:30 gm truck position rather then the above the water pump mark, can the car even run with it being 40 degrees off like that?

 

Is it running?

Yes/no

Yes: it obviously can.

No: maybe not.

Put it where the car runs the best. EFFF abuncha "spec" and "book" and "mark" and "light". Especially when YOU ALREADY KNOW the whole "mark" system is fornicated.

If it RUNS good, it IS good.

That's all you need to know.

 

i want to get rid of the random misfires at stoplights, i ask about the 40 degree because i find it strange its that far off and can still run

 

I should mention, first thing I'd look at for a "random misfire", is the spark plugs. Put in NEW ones. Not, "check"; not, "PO said she just changed em"; not, "they look fine"; NOT NOT NOT NOT NOT NOT NOT NOT. Put in new ones..

"Timing" won't create a "random misfire". Spark plugs will. Use logic and focus your mental energy where it can actually work.

See my signature for some help. "Timing" is NOT an "explanation" that fits ALL the facts for a random misfire.

 

just put in acdelco plugs,new cap rotor and wires

 

Somehow I just KNEW that was coming...

So, since you did it AFTER it began misfiring, did it fix it?