Stutters when floored

**alkygto** · 01-15-2010

Already replaced fuel filter ( Had to install new pump last year ) How can I check for knock? or is that the KR talking now? it never happened before and I have'nt really changed my combo. I'm gonna check plugs and then swap back to the original coils next. Sorry OP to jack your thread, still on topic though. What is the best all around set of headers and crossover as far as price, fitiment and quality? Thanks

**matt5112** · 01-15-2010

http://www.grandprixforums.net/f81/h...ead-25922.html

Yes, knock causes knock retard.

**alkygto** · 01-15-2010

Originally Posted by badbrad

i put i think msd wires(got them on clearace at advance) long boots. no more glowing ring around plugs...do easy stuff like fuel filter, gotta check for cat operation..new denso(my choice) o2 sensor, make sure u didn't break ceramic around plugs(i have),good wires, check coils, and auto store should be able to check icm.....i think thats it, my head hurts.

Take an asprin lol, I've been chasing gremlins on this car for a while now, had an ABS light and TP light on, just replaced front hubs last year ( also upgraded to the 12" discs

) and thought

, turned out to be a broken wire in the harness.

**alkygto** · 01-15-2010

Originally Posted by matt5112

http://www.grandprixforums.net/f81/h...ead-25922.html

Yes, knock causes knock retard.

I get that, but I really have'nt changed my combo, been running it for years like this. I'm chomping at the bit for the pacesetters now, but I need to get current problem figured out. Car runs fine besides this. Thanks so much for the above link.

**JoelW98GTP** · 01-16-2010

Originally Posted by alkygto

I get that, but I really have'nt changed my combo, been running it for years like this. I'm chomping at the bit for the pacesetters now, but I need to get current problem figured out. Car runs fine besides this. Thanks so much for the above link.

KR can show up with climate differences, fuel octane inconsistency, humidity, etc. Put the headers on. If its KR, headers will help. Invest in an Aeroforce Interceptor if you have the money. You can scan for KR this way and be for sure. KR is probably your gremlin. That's why I still run my stock pulley. My car will run better the way it is with no knock than with a 3.4 with knock. If you don't have the money for an aeroforce, put the stock pulley back on. Your will save your motor if it's KR. If its not KR you're not out anything.

**kamamm** · 01-16-2010

could be your catalytic converter getting plugged

**alkygto** · 01-16-2010

Any quick way to check for the plugged converter? Should it throw a code? Seems everytime I wrench on this thing I get another problem. My GTO has carbs and a magneto, that I can deal with. Anybody know how many miles of wire in a GP?

Love my GP!

**matt5112** · 01-16-2010

Quick check is unbolt the downpipe then try driving like that.

If it no longer stutters, its the cat, if it still does it, reattach and keep looking.