Tune Up Done....

RyanZ71 · January 2, 2005

Last night I decided it was time to change the spark plugs and plug wires on my 99 Silverado with 91,000 miles. I thought it would be painless but boy was I in for a night. I thought I had all the right tools, spark plug socket, socket extenders, adaptors, etc. I picked up a set of spark plug wires from PEP BOYS a few weeks back along with a gapper tool. Off of E-Bay I purchased 8 Iridium AC/Delco 41-985 Spark Plugs. I logged onto the AC/Delco website to determine the proper gap of the new plugs, it said and I quote: "GAP .040 DO NOT DEVIATE FROM PRESET GAP .040" well these plugs that I purchased didn't come gapped at .040! More like 0.30 unless of course my gapper tool was off which is possible since it was a $2.00 part but was the best one they had, seems hard to find a good quality spark plug gapper... So I gapped them at .040 and then went out to the garage and proceeded to remove all the coil/plug wires (whatever the proper term was) and started on removing the plugs on the drivers side. WHAT A PAIN IN THE BUTT! Those things must have been torqued at 100 lbs at the factory! Not to mention even having all the socket tools, adaptors extendors etc still made it VERY difficult. The plug on the drivers side closest to the firewall was so hard to get loose and out of there the plug cracked and broke and I think I might have cracked the new one when I attempted to tighten it down. Then came the Passengers side, they were ok except for that pesky one nearest the firewall. I SPENT OVER AN HOUR GETTING THAT THING OUT AND TRYING TO GET THE NEW ONE IN!!!!! The old one broke in half and I had a heck of a time trying to get the spark plug socket on it once it had broken in half! I ended up having to crawl under the truck reach my big hands up around the exhaust and heat shilds and whatever else is under there in order to get the socket onto the spark plug!! Add to that the socket falling off a few times and hitting me in the forehead! Finally was able to get it to stay on while I crawled back into the engine compartment to finish removing the plug. With that done and the new plugs in, I put on the wires, Re-connected the battery and said a silent prayer and fired her up. To my suprise she started right up and sounded smooth. I performed the idle re-learn procedure and took her out for a spin. She seems to be a bit more responsive and idles smoother now. The old factory original plugs looked very nasty, I am glad I decided to change the plugs now instead of waiting for 100,000 miles. I plan on replacing the new set of plugs at 150,000 miles as I do believe that 100,000 miles is just too long of a time to wait no matter what the so called experts say. I will however have a mechanic/dealer perform the work as I need my hands in as good of condition as I can for my job! My advice is if your thinking about replacing your own spark plugs, don't do it, take it into a mechanic to do it who can get the truck on a lift, has more tools and more patience.

JCedar · January 2, 2005

Use anti-seize man, they'll come out no problem.

99silveradoz71 · January 3, 2005

Nothing wrong with being a bit early on some of the service.

rkn2903 · January 3, 2005

Ryan how do you perform the idle re-learn procedure, because I done my tune-up a few weeks ago, with the same plugs off ebay but I didn't know anything about the idle re-learn procedure.

rkn2903 · January 3, 2005

Just found how to do the idle re-learn procedure.

az'03Silverado · January 3, 2005

Sounds like a fun experience! I used to have a '98 S10 Ext cab with the 4.3L V6 and a 5 speed. I decided to change the plugs one day and 5 of them went fairly easily but the one in the middle on the driver's side is right behind the steering shaft. It friggin sucked. One trick I learned that I'll pass on. If the plug is in a tight space, put the plug socket on the plug (it should stay with the rubber piece inside). Then, use one of those short-handled wrenches (not the ratchet) on the spark plug socket. It should have a hex shape on the end. This lets you work in a tight spot a little easier. I know this tip does you no good now but maybe some time in the future.

But, look on the bright side. The job is done. The truck runs better. And you learned something in the process. Well worth the frustration. Oh, smart move changing the wires while you're in there. Lots of people forget those and then have problems later.

HDChuck01 · January 3, 2005

I need to tune up my 96. Is it any different on the 5.7 vs. 5.3? I'm worried now that i might have a hard time. I have 103000 miles on it and i think it's time. Stealer wanted $400+ to do it for me!

Ddexter · January 4, 2005

So, how is the idle re-learn procedure done?

Forget it .. I did a search and found it.

rkn2903 · January 4, 2005

My plugs where pretty easy on my 99 SLT 5.3L.

RyanZ71 · January 4, 2005

My plugs where pretty easy on my 99 SLT 5.3L.

<{POST_SNAPBACK}>

What do you mean pretty easy!? Its the same truck as mine with GMC on the front of the Grill and different looking headlights! How was it easy!?

thirdgoat · January 4, 2005

OK, I give up. Idle relearn procedure? I checked my shop manuals and they make no mention of it. I recently bought new wires and plugs for my 99 Tahoe, read Ryan Z71's post, but now I am confused about the procedure. From what little I can find, it is to be done after disconnecting the battery, but again, no menti0n in my shop manual?

What is the procedure, or do you have a link?

Thanks!

kdm101 · January 6, 2005

I replaced my plugs around 45K. Wasn't that hard to get out at all. I've seen on past posts, that the longer they've been in, the harder they are to get out. I did use a dab of copper anti-seize on the new ones before the new ones went in. Should be just as easy to get out next time.

Even at 40K, the plugs looked like crap. Some, possibly from day 1, were way off on the gap.

igbig · January 6, 2005

I agree with RKN 2903 . Ive changed my spark plugs twice and my wires once. and they were pretty easy. with the exception of the passenger side one closest to the firewall. I use a "wiggler" with a piece of duct tape wrapped around it for almost all eight plugs. The tape helps it from moving too much but still lets it bend and get into position. Im not trying to flame you Ryan but I think it just depends on a persons mechanical skill level. If you think the plugs on our trucks are difficult to change try doing it to a 1992-1997 Z28.

On a scale of 1-10 for dificulty i would say changing the plugs on our trucks is a "4 ". ands thats only because of the difficult one by the passengerside firewall. otherwise it would be a "3".

Bill55AZ · January 6, 2005

One thing that helps with tight plugs, use compressed air to clean debris from the area around them, then spray some WD40 or equvilant and let it soak. Sometimes they come out easier if the engine is still a bit warm.

And if the 3/8" socket set won't do it, get out the 1/2" stuff, including the breaker bar, and use 6 point impact type socket. I swear the lighter duty tools flex and bend, preventing you from getting good leverage.