Old spark plugs,how much can affect performance?
08-16-2007, 11:09 AM
#1
Le Mans Master
Thread Starter
Old spark plugs,how much can affect performance?
I got my corvette last weekend,the idling is really rough and the power is not much outstanding,i ve been told that the spark plugs havent been replaced since 2002,i will change them asap
but how much can affect on a ride having old spark plugs ?
thanx !!!!
but how much can affect on a ride having old spark plugs ?
thanx !!!!
08-16-2007, 11:12 AM
#2
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It depends on how many miles are on them. Also if there have been fuel related issues that caused a plug to foul. they should be replaced. In any event, after 5 years they should be changed.
08-16-2007, 11:17 AM
#3
Race Director
Five years is not old for a plug, how many miles? They could cause a rough idle but I would bet it is something else. They are cheap and not to hard to change though.
08-16-2007, 11:54 AM
#4
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Age and mileage don't necessarily dictate plug life, however they are both factors. Usage can erode the electrodes and increase the gap. Deposits and contamination can foul the plug and short circuit the gap or insulate it, preventing the spark from igniting the fuel mixture. Otherwise if they are still clean and firing, they are probably OK. The plug goes ZAP then the A/F mixture goes BANG. That's all it takes. Your problem could easily be plugs... or not. The plugs in my old carbed '78 pick up, factory built with no smog equipment, haven't been changed in this millennium, but it still passes the smog test for my EFI Corvette.
RACE ON!!!
RACE ON!!!
08-16-2007, 01:03 PM
#6
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What shape are your coil and ignition wires in? The O.E.M. ones are good for 60,000 miles tops.
08-16-2007, 02:12 PM
#8
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Originally Posted by Calderone
They are good they look good
i will replace them anyway
i will replace them anyway
RACE ON!!!
08-16-2007, 02:20 PM
#9
Race Director
Why waste the time and money if that is not what is causing the problem. You want to fix the issue right?It sounds like it is back firing? Or is the exhaust just hitting something?
08-17-2007, 10:45 AM
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Open your hood at night or in a dark garage with the hood lamp fuse pulled and start the engine. Look closely at your coil wire and ignition wires.
If you see the dreaded electrical creepy-crawlies, it's time to replace your wires. You can also mist 'em with water from a spray bottle to spook any wiring gremlins you might have.
If you see the dreaded electrical creepy-crawlies, it's time to replace your wires. You can also mist 'em with water from a spray bottle to spook any wiring gremlins you might have.
Last edited by onedef92; 08-17-2007 at 10:48 AM.
08-17-2007, 11:38 AM
#12
Le Mans Master
You also might want to check the resistance on your injectors, my 89 started missing bad last week and someone on the forum said to check the injectors and sure enough one was reading 8.5 instead or 16.5 like it should have been. WW
