I just bought AC Delco Plugs

I just bought AC Delco Plugs for my 1999 SL1. I took them out of the box and the washers were seperate in the box. I put the washers on the plugs ans noticed there was 2 different sides to the washers. Does it matter on the way the washers go on the plug?

Called local garage and was told flat side towards head.
Installed plugs andWOW!!! what a difference!
It had platinum plus 4 plugs. Thet were black on one leg of the plug, but clean. No oil or grime. But I got Alot more power now!
Runs smoother also!!
Ac Delco is the way to go with gm products.

I"m with you. Price is great and works better than platinum. NGK are oem tho.

well there was your problem, bosch platinum 4s let alone its a bosch plug. they dont last more then a week. they are junk. sometimes they seem to work fine in euro cars, like bmw, but not american or japanese. im running ac delco rapidfires and so far out of all the plugs ive tested, its the best. ive ran ngk v-power and they were fine but no where near as good as the rapdifires. i also have a set of denso u-grooves to test when i want to pull my ac delcos, which i dont. i test many spark plugs, because they are cheap and i just like to have fresh ones quite often.

now hearing the plug being black, yes its a bosch but still, you might want to look into a bad ects too. just a side note, car can run fine with a bad one but gas mileage wont be so great. if you do replace it go with dealer part and probably the connector too, since they tend to corrode up in the connector and down the wire. but its your option, might have been just the boschs were so crappy they got that way.

now hearing the plug being black, yes its a bosch but still, you might want to look into a bad ects too. just a side note, car can run fine with a bad one but gas mileage wont be so great. if you do replace it go with dealer part and probably the connector too, since they tend to corrode up in the connector and down the wire. but its your option, might have been just the boschs were so crappy they got that way.

I did replace the ects, but that was before i found this forum, so I dont know if it is brass or not.
I just replace a o2 sensor that " was slow to respond" according to autozone reading the code. I cheaped out and bought universal ( it was the one before cat).
gas mileage was down tho, last tank I only got 34mpg last tank, it was consantly 38mpg before the check engine light.
That makes me think the platinum cant handle any variation off perfect on fuel mixture. Then again I had a fiero that had a msd rapid fire ignition and ac delco and was "hell on wheels" and those " gimmick" split fire and plus four" was a piece of s*** compared. [B]So Im sold on ac delco on all my gm products!

sounds like its doing fine then. but platinums have never been an issue with me or in my saturn or any car. i think most guys were saying platinums suck in saturns because they were using bosch plugs, which just plain out suck.

sounds like its doing fine then. but platinums have never been an issue with me or in my saturn or any car. i think most guys were saying platinums suck in saturns because they were using bosch plugs, which just plain out suck.
the saturn ignition system fires plugs completely opposite of how platinum plugs needs to be fired. that's why they don't work.

well then i dont own a saturn. platinum plugs arent an issue. and this talk about saturns arent meant to fire platinums?????? any car can fire one. the only bad thing going for a platinum is the fact it has the most resistance. if you want least resistance, go buy silver ones which also have the lowest melting point and is next to last in hardness.

Well The car had platinum in it when I bought it. I have put 20,000 miles on it and the plugs were not missing, the car just didnt run right. It was sluggish and jerking on acceleration. And were blck looking when I took them out. No oil or grime on plugs, acually they were clean except for the fact they were black. I have found over the years that gm products work better for me with GM parts.
not to say others don t work, just not as good as oem.

I have used bosch 4s in my wife crown vic with no issues. They were extremely pricey and did not improve the mileage as claimed. The car ran fine tho.

I have a sc2 that i run ac delcoes in. They run fine and are a third of the cost of the platnimum bosch plugs. The explanation I have read about not using platinums in the saturns has to do with the ignition system firing on both the compression and exhaust strokes. Also something about the firing is in reverse, jumping the spark from the center electrode to the smaller prongs, which doesn't work well for one reason or another. Can't say I totally understand it but I won't waste the extra money for something that offers no additional benefit.

I have used bosch 4s in my wife crown vic with no issues. They were extremely pricey and did not improve the mileage as claimed. The car ran fine tho.

I have a sc2 that i run ac delcoes in. They run fine and are a third of the cost of the platnimum bosch plugs. The explanation I have read about not using platinums in the saturns has to do with the ignition system firing on both the compression and exhaust strokes. Also something about the firing is in reverse, jumping the spark from the center electrode to the smaller prongs, which doesn't work well for one reason or another. Can't say I totally understand it but I won't waste the extra money for something that offers no additional benefit.


well the only real benefit from platinums is the life of the plug. thats pretty much it. ive ran platinums in my car and didnt notice any increase in gas mileage, throttle response was same or better depending on the plug, and always ran fine.

My 2 cents...
I bought 4 Bosh Platinums for an old car, figuring those plugs would last the life of the car. They were the plugs specified for the engine.
The car started smoking badly after a while (can't remember how long, less than a year). I took out the plugs, to find that 2 plugs had dropped the insulator into the engine. I put the old plugs back in, and added "no-smoke" type stuff to the oil for the rest of it's life. I won't buy Bosh plugs again.

Plantinums suck, thery will work fine for maybe 5-8000 miles, then they go poopy. NGK coppers only! V-powers!

Plantinums suck, thery will work fine for maybe 5-8000 miles, then they go poopy. NGK coppers only! V-powers!


no they dont, BOSCH platinums go out that quick. with good platinums they will do fine and last long.

everyone who doesnt get it, its not platinums, ITS THE BRAND!