Hello all. I installed new plugs yesterday, and the car runs smoother, more powerful and has a smoother idle. BUT now the SES light has come on. It stays on steady.

Used NGK TR55's, car has 43,000 miles on it. Checked all wires and they are secure.

I did not swap out plug wires, they looked good. They are the factory wires.

Any ideas on what I can check before I have to take it in to get the code read? I read on here that someone took their car to AUTOZONE to get a code. Do autozones provide that service for free or do they charge something?

 

it is free at Autozone.

 

Thank you PJB.

 

Just FYI:

I went under the hood and unplugged and re-plugged every wire I could find. When I started the car again the light was still on, but a couple of starts later and it was off. I drove around for about an hour and the light has not come back on.

Hopefully that will be the end of it. Just a wire I had not re connected well I guess.

The car is running stronger and smoother than ever.

 

I am in the middle of installing ngk tr55's and msd wires too. My car has 43,000 miles on it to hoping I can get the same results you did. By any chamce did you have burnt oil residue on the old plugs?

 

No, no oil residue at all. In fact, they were really whitish-grey. I think that means it was running lean, or too hot? I'm not sure. There was some carbon around the edges where the plug meets the head, but no oil.

Did your old ones have some burnt oil on them?

Also, let me know how you got plug 8. That thing took me over an hour to get ahold of just to turn. I used spark plug socket, 1 inch swivel extension, 3 inch extension then the ratchet. All 3/4 inch. I almost left it in it was that hard, but when I crawled under the car a second time I could see I had turned the plug by the writing on it! So that kept me going. Good luck and let me know how you make out.

 

8th cylinder is a the easiest to get! From under the car anyways, I use a lift at work, but I could see it being just as easy under the car on the ground. The rest of them are the hard ones..

 

i do believe that a ses light means you have an emissions snafu. did you loosen your air pipe during the install? might wanna check that. fwiw, i installed the # 8 plug from underneath and it took like 10 minutes. just drove the car up on ramps.

 

That is what everyone tells me, that #8 is easy from underneath, but I put mine on ramps as well to try from underneath. I could see #8 plain as day, but the exhaust is so close to the wheel well my hand would not fit up there to even grab the ratchet. Believe me, I tried. Maybe mine has a different exhaust set up? And the starter is in the way for #6 from underneath.

It was not easy doing from above, that is for sure.

 

I was installing kooks lt's when I changed my plugs so everything was really open and easy to get to.

 

#8 is one of the easiest plugs from the top .... actually they are all easy with the QTP headers
Takes 30 to 45 min to gap the plugs and do a full swap.

 

Changed mine a while back-It was the best use I ever got out of my BMR STB-you gotta climb in there. Oh yeah, number 8 from below on jackstands. Its tight but with the right combo of extensions, swivels and wratchet sizes it went surprisingly quick.

 

i've got skinny forearms so it was easy for me to do. the cat was even a little hot when i changed it. so how'd you get it? take the coil packs off, and from the top? i've heard some gm techs won't mess with #8. i know there are differences between 98-00, just not the particulars.

 

I got if from above. Removed all the coil packs except #8, because that would be impossible. Removed AIR tube as well. Used spark plug socket, 1 inch swivel extension, and ratchet. Took 40 minutes to get it out. It was not fun and my hands look like they went through barbed wire. I will seriously consider taking it to the dealership next time.

 

The 98's exhaust manifolds make it difficult to get to # 8 , compared to the other years. My 99 with headers takes all of 15 minutes for #8. Headers make it easier on all the years.

 

Sweet, I now have documentation to show my wife that I have a mechanically necessary reason to install headers! Thanks VIPER!

 

No problem, and write the board back if you need help!!

 

Hey Viper,

How can I be sure when ordering headers if they will bolt right up to the factory cats? I want to do headers first. Then cats with Y pipe. Then exhaust. I have to do them one at a time due to $$$. Some of the headers I look at online look pretty dang long. Do I want to avoid the "long tubes"? I assume when I get ready to order I can just call up and ask the retailer I guess?

 

As far as I know, only shorty headers ( JBA, couple of others ) will bolt right up to existing cats. I vote don't bother; save for a set of longtubes and get Random Tech cats. The shorties have helped some , but unless you're worried about emissions ( California requires shorties I believe ) go longtube as the gains are awesome ( 20-30hp depending on factors like what year car, aftermarket cam, intake etc. ). Again with emissions, you can go no cats if you don't have testing. You can also contact Stainless Works, a vendor on LS1Tech.com and ask for Al Noe; he's a personal friend and will set you straight. If you call, mention me ( John Tokar ).