Misfire after plug change, need expert help please!

Anyways, stay away from the NGK G-Power plugs (not to be confused with the V-Power ones, that apparently work). And always try the simple things before suspecting the DIS etc.

Thanks for all the continued help from everyone, always a pleasure!

-Derek

super old post but just thought i would add... its funny, I used the G power plugs for my 95SC that i have now and the car ran fine.... i Put in a set of the V power copper core ones and it has similar problem as you did, massive misfiring. i havent gone crazy yet, but after reading your info, im gonna change plugs again, maybe i got a bad one in there.
 
Help with misfire!

I have a 1992 super coupe, 135k miles. Had a misfire when I got it after sitting for a few years. I changed the plugs and wires, plugged it in to a scanner and it came back as "dist coil" so I replaced the coil, and camshaft positioning sensor. Idles around 600 and only builds about 4 lbs of boost. I've checked the typical vacuum areas also, cleaned the MAF and throttle body... Please help!
 
I have a 1992 super coupe, 135k miles. Had a misfire when I got it after sitting for a few years. I changed the plugs and wires, plugged it in to a scanner and it came back as "dist coil" so I replaced the coil, and camshaft positioning sensor. Idles around 600 and only builds about 4 lbs of boost. I've checked the typical vacuum areas also, cleaned the MAF and throttle body... Please help!

Since you changed the coil & wires...did you confirm the firing order? At least one book out there has the wrong example.

See: http://www.sccoa.com/forums/showthr...re-and-much-much-more!&highlight=firing+order
 
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I have a 1992 super coupe, 135k miles. Had a misfire when I got it after sitting for a few years. I changed the plugs and wires, plugged it in to a scanner and it came back as "dist coil" so I replaced the coil, and camshaft positioning sensor. Idles around 600 and only builds about 4 lbs of boost. I've checked the typical vacuum areas also, cleaned the MAF and throttle body... Please help!

Oh man. I am having horrible flashbacks since you brought this post back to life. I think the SC gave me ptsd. I have since got rid of my SCs but still cringe thinking about all the issues I had to sort out over the years. Good luck with the car.
 
Firing order is confirmed, based on the vin. My next guesses are either a stuck injector, or maybe plugged cats? Someone suggested the ecm but im not sure that's the problem.
 
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My next guesses are either a stuck injector, or maybe plugged cats? Someone suggested the ecm but im not sure that's the problem.

The odds of those suddenly becoming an issue following a plug change are fairly low, I think.

Usually when this comes up, it's found to be one or more plug wires that weren't properly seated (especially given how hard it is to change plugs/wires on an SC and/or cracked plug(s) and/or improper gap(s)/plug type.

If you're discounting those possibilities, I'd at least check for codes.
 
The odds of those suddenly becoming an issue following a plug change are fairly low, I think.

Usually when this comes up, it's found to be one or more plug wires that weren't properly seated (especially given how hard it is to change plugs/wires on an SC and/or cracked plug(s) and/or improper gap(s)/plug type.

If you're discounting those possibilities, I'd at least check for codes.




I was having these problems before the plug and wire change, that's what I thought the problem would be. It sat for 6 years before I got it, only got started every few months. I had it scanned and it came up as a "dist/coil" code, so I changed the coil and cam sensor with no difference. Also when I had it scanned, came up as code "216" and wouldn't let me clear the code.. which makes me think ecm...
 
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