StuntmanMike

iTrader: (2)

I was planning on doing the plugs on my Formula today. It's an '00 with 77k miles. I had assumed they'd be the originals, but when I pulled one of them out, it was a Denso. Stock would be a Delco, correct?

Here's a few pics of the Denso (left) next to a brand new Delco Iridium:





Should I change them out, or just leave them in?

bigti99a

iTrader: (16)

if you have everything you need i would just change them. dont forget to put some anti seeze on the new plugs.

stevied916

iTrader: (30)

they dont look bad. check the gap on them though

bczee

iTrader: (12)

looks like you been running a bit rich.. What type of plugs were/are the Denso's ?

The center electro seem ok, but if you got the plugs and some time.. I'd change them anyway if they have been in for a prolonged period of time.

Luder[PAK9]

Some people have reported having their cars come from the factory with Denso plugs, so they could be stock.

z-ya

iTrader: (1)

Denso came stock in my 2001.

StuntmanMike

iTrader: (2)

Hmmm, that's interesting. The wires look to be in decent shape too, they're Delco, so they could definitely be original.

I'll go ahead and do it, it'll give me something to do today. I also have MSD wires to go along with the plugs.

I'm a little mystified though, The car runs a bit rough at idle, and it seems to have gotten worse over time. I thought it was the fuel filter, but I changed that and no change. So then I figured maybe it needed plugs, but these don't look bad at all. I also cleaned the TB a few months back thinking it could be that (I had a similar problem on my Jeep and that cured it).

lovescamaros28

The spark plug looks right on to me.I dont see any reason to change them out.

StuntmanMike

iTrader: (2)

I ended up getting the driver's side done. Not bad at all, took me about an hour, including time spent posting about it here.

I had wanted to get both sides done, but I realized I didn't have the tools to get the EGR stuff on the other side. I just had my small socket set and ratchet with me today, I didn't have a box end or enough extensions to get to the 2 10mm's holding it on the manifold.

Even with only one side done I noticed a difference. I didn't drive it, I just started it up, but throttle response seems much better, it definitely revs much faster.