Black 99 Bird

iTrader: (31)

I started to change my plugs last night and got half way done (replaced all plugs on drivers side) and decided to wait until today to replace the rest of them. This morning I jumped in the car to run to the grocery and the car ran fine on the way there. But on the way back I decided to get in it a little bit and the car is missing badly above 4500 RPM at WOT. I took a detour to try it out again and it does the same. Before you ask I did not replace the wires and I used NGK Iridium plugs. I falied to use any dielectric (sp) grease on the wires. Does this sound like a plug wire problem? The car ran fine before I worked on it last night, just had a little hesitation, but still ran hard. Now it is running like ****. I checked and rechecked all wires before I fired it up this morning and everything appeared to be in order. The car runs perfect during normal driving but once you get in it and get past about 4500 RPMS it cuts out like a b!tch. Should I pull the wires off again and put some grease in them, could this be the problem? The car did not set an SES light, which I thought was odd considering how it was running. All help is appreciated!

Tom99SS

iTrader: (2)

Make sure the wires are on correctly. Double click at coil and single click at plug. Also, recheck the new plugs for gap. May have accidently closed a gap while installing.

Pegleg

Yea you need to double check everything to make sure its on tight replace the other plugs and check everything again.

TheBlurLS1

iTrader: (8)

It will only set the SES for multiple missfires.

2K2WS6TA

iTrader: (2)

FWIW one of the new plugs could be defective, just because it's new means nothing
Carefully check the white porcelain part of the plugs for cracks, or put the car in a dark garage and rev to 4500 and look for arcing, chances are that will be the bad plug

Black 99 Bird

iTrader: (31)

If I had a problem plug, wouldn't it show up in normal driving? Thanks for the help guys, I guess I'll yank them all and check them out.

SPEEDYws6

iTrader: (9)

Not always... I recently put together a Buick Grand national for a customer and I left one wire lose. The first test drive I didn't get in it and the car ran perfectly. Next time out I decided to get in it and the car would miss badly under boost. Went to check the gap on the plugs and found the lose wire.

At WOT more spark energy is required to ignight the mixture, most likely you have a lose wire and the current is taking the path of least resistance which isn't throught the plug at WOT.

Black 99 Bird

iTrader: (31)

I need new wires anyway, 97K on factory wires. I'll put in a order for some MSDs today. I'll post up if it fixes the problem. Thanks for all the help guys!

shaun

could have also cracked a plug when installing them

Mike02Z

iTrader: (13)

HOLY COW! I chucked my factory wires at 25k! Actually I still have them in case I need one but yea, I'd say replace the wires. The factory says 100k bt that is total BS. I wouldn't keep any wires on that long. I got my MSD's from an ebay seller brand new for 55 bucks. Most places wanted 75-90 for the same set.