Well, I happen to be one of the lucky people who do the most obvious and cheapest replacement first but it never solves the problem.

My vehicle is a 1997 Pontiac Firebird Formula. I bought it used with about 40,000 miles in the summer of 2001.

I have read on this board for months and months since this problem started happening to my car last summer about so many different things that could be causing the bad performance stumble.

Optispark
Bad Spark Plugs
Bad Spark Plug Wires
Exhaust Leak
Plugged EGR Valve
Fuel Filter
MAF Sensor
MAP Sensor
Intake Bellows
Plugged Cats
Bad O2 sensor(s)

Well, I have replaced a few inexpensive things in the past few months: Fuel Filter, Intake Bellows.

But

I decided to bite the bullet and replace the spark plugs and wires as the first major overhaul of the Formula. I purchased MSD 8.5mm wires with the Boots for the LT1, and Splitfire Triple Platinum spark plugs. Well, I found a local mechanic who said he could do it, but it would not be cheap. I said no problem, have at it! Well, I stepped out and walked out to do some other shopping and grab some lunch. I came back about 3.5 hours later and he was just fininshing up on the passenger side plugs and wires. The drivers side was not even done yet! I asked him how much longer he thought it would be - he said probably another hour. Well, The plug under the alternator (I have no idea of the plug #) was the hardest for him to get to. But he had a suprise in store for me.

The stock plugs for this car were AC DELCO platinum plugs. Well, the other 7 plugs were autolite plugs, the one under the alternator was....... the original stock spark plug. So, someone tuned up the car before me without changing that plug. Well, the little platinum puck was gone from the terminal, it was glazed from top to bottom, and the gap measurement was insane!

Well, he changed out the passenger side, then the drivers side and got everything connected, he brought it down from the lift and I took it for a test drive. I have two words to explain what I felt when I mashed on the gas.

HOLY SHNIKIES!!

There was no hesitation in first gear anymore, there was no simulated "rev limiter" miss at the top end of second and third, and the high gear miss was gone too (When you are in 5th or 6th gear travelling 40-60 mph and try to accelerate - the car would buck like a bronco)

If you guys have the means and the money (this little upgrade cost me $275 for the install, $72 for the wires, and $48 for the plugs), I highly recommend replacing your plugs and wires ASAP!

Adios!

CCRJon

 

I'm glad to hear you got it running just right. Sometimes it is the simple inexpensive things that go bad and cause a costly and serious problem for the owner.

I've heard the "repair shop spark plug" story a few times. I am amazed that so many repair shops cut corners and shaft unwitting customers.

 

i've heard of people not changing that one plug. thats the biggest bunch of crap i've ever heard. its really not that hard to get if you pull the alternator and put an open end wrench on the 6-point end of a spark plug socket.

 

This is very common, 4 of the 8 plugs in my car had the pucks missing after only 25,000 miles.

 

That's the way I do it. Not hard at all.

 

Its easyer if you have headers, or if you drill a hole in the side of the wheel well and go in with a swivel socket... Just be carful of your Air Condintioner lines.

 

I had a similar problem with my 94 z. Except my story goes that a chevy dealer put the cheap ac plugs back in instead of the correct platinum plugs. I had a miss after warming up as well.
$275 for that was not bad I recently paid 300 for the exact same job.

This past weekend I went to a new car show and I looked at the 50th ann. corvette with the ls1. The plugs could be changed by goober pyle of mayberry - there right there toward the top where they should be. It really angers me that we go through such problems just changing plugs and wires.

 

$300 for a plug change? the garage i always take my Z to charges me $80. i always buy AC Delco Platinum's and just drop the car and the plugs off with it. I'm glad my garage hasn't heard what everyone else is charging for plug changes. i also ALWAYS make sure that i tell them to put the old plugs back in the box so i can take a look at them. never had a problem and i guess i can now say i get a good deal. glad you got your miss fixed!

 

$300 DOLLARS!!! Good grief!! I did my plugs and wires in 3 hours using some ramps, swearing and BEER!! If you want, I'll change your plugs and wires for $100 dollars an hour!! Honestly, I would suck it up, buy some $25 ramps, take a Saturday morning (that way you're running by evening) and do it myself. I can definitely think of a better way to spend $300 (cat-back, 1.6 RR's ?)

 

Well, let me clear up something i left out. The 300 also included labor for putting on new plug wires. I provided the plugs and wires. But you still got a great deal labor for the plugs alone was about 150. This was at a chevy dealer - so I knew I would get a new one ripped for me - if you know what I mean. However here in rural MS, about 90 percent of the shops have never worked on a z 28 - the v 6 cars are a big challenge to many of them. That's why i wen to the chevy dealership.

The bright side is both our cars are running good. Next week I am going to geet a new set of z rated tires and get rid of those h rated i am riding on now.

 

I'm in the same boat up here in rural SD, and they are actually SCARED to touch a 4th gen!! I went in this weekend about getting a new exhaust from the y-pipe back, and they actually tried to talk themselves out of it!! Can you believe that? One shop said that if I went with a 3" I-pipe, I would actually LOSE power! - That is, until he looked in his "manual" and found that it is acceptable!

 

You must understand I normally do these things myself, but the weather here has been terrible rain and cold. The camaro is a standby for my wife who is working and finishing a degree. She drives my 92 chevy truck with 250000 miles. So it does have a little wear. Bought new in 92 oil change every 3500 miles, 30,000 mile tune ups and only replaced an alternator and clutch one time each. Still getting 20-22 mpg on highway and that is with the mighty 350.

 

On a couple occasions I have stopped to get gas or an inspection sticker when I have been out of town, and people woould ask what kind of car it was (my z 28). They thought it was a foreign job. Typical non car people. I am probablly going to get an slp loudmouth for my car soon I have a k and n fipk and the rest is stock.

 

I would go with the MAC. It sounds better as well as looks better, same price.

 

I can say it until I'm blue in the face. Plugs & Wires should always be the first thing to check. I went through the same thing 2 summers ago. I had new plugs & wires on the car & didn't think it was my problem. I mean no way. They were new. Well my #7 & #8 plug wires were cracked with hairline cracks thay you could not see unless you bent the wires a certain way. I changed them all & new plugs & like you said. Holy Shnikies!!
And that was after the dealer said my opti was shot & nailed me with a new one!!!!

Always check Plugs & wires first.