I'm planning to change the plugs in my 2000 2.9 s80 this weekend.

It looks very straightforward - any nasty surprises waiting for me?

 

Not a hard job at all. If they have been in a long time, squirt a little blaster down the plug so that when you loosen them, there is some lubrication. I've seen these things done with no anti-seize paste and you can really gall the threads. Make darned sure you put anti-seize paste on the threads of the new plugs.

Use an old section of vacuum line to start the thread in the head.

 

+1 Tony1963

 

Surprisingly non-eventful!
Plugs came out no issues, back in with no issues (and anti-sieze paste). Way better placement of plugs than the last car I had which had a sideways v6...
Got a good look at the timing belt - if it's really got 80k on it it sure doesn't look like it since it looks like new. I got the car with about 65k on it and I have not put a new one on.

 

it's not so much the timing belt but the tensioner that fails, may be time to change.

 

I changed mine years ago with fancy platinum (single electrode) pluges. Simple process but the car ran bad when cold. I replaced with multi-electrode plugs and all was well.

Careful in what you replace with.

 

I replaced mine with bosch +4
Hopefully that was a decent choice. So far it hasn't seem to be any difference which is a little disappointing - if anything, it seems like my mileage may have gone down a bit recently.
The plugs that came out said Volvo on them and had 3 prongs and with 80k on them and looked pretty clean. Probably didn't need to change them.

 

good luck ..u can make a DIY with pictures

 

http://www.matthewsvolvosite.com/for...p?f=11&t=17431

 

Silicone spray inside plug boots is a good idea! Knowing the heat range of plugs is important. Sticking with Volvo recommended parts from dealer or parts store is safer. Some more exspensive plugs can be bad for your engine performance, personal exsperience proven!

 

I use NGK iridium plugs in my 01 s80 2.9L with 186K and get 27mpg highway/ city ? usually 23-24 mpg to the tank.

 

Lunger,

If I am reading you correctly, your saying your switch to the NGK iridium plugs gets you 27mpg highway/city (combined) where you usually only got 23-24 mpg?

I have 120k on my 2002 S80, and I am guessing they have never been changed, so I am looking for recommendations on plugs.

 

follow up: We just did a 600+ round trip and mileage seems to be back on track with about 27. I think I had a bad tank of gas around the time I changed the plugs along with having 0 highway miles around that time, either that or the car's computer was adjusting to the new plugs somehow. Just glad I don't need to pull the new plugs and hunt down something else.

 

no I was saying that I get 27mpg highway. I wasn't sure what the city was but that I usually average 23-24 mpg per tank so that would mean city would be around 21 or 22mpg

 

Thanks for the clarification Lunger. I have a 2002 S80 (2.9 non-turbo) I traded for when it had about 90k miles. No service records came with the car. I assume it has never had the plugs changed. Now has 119k miles.

Highway it will do 30mpg on regular gas, which is not bad at all, but city it is not so great. Looking here and elsewhere, people seem to be getting better city mileage than me, so...

I was thinking of changing them. But, no way am I going to put in expensive $8.00 Iridium plugs if they wont do better than what I have now. I was looking at some Bosch or NGK Platinum at the parts store for $3.99 or $3.19 each, respectively.

Open to any and all suggestions.

 

for your reference

https://volvoforums.com/forum/volvo-...-fusion-43334/

https://volvoforums.com/forum/volvo-...s-volvo-13280/

https://volvoforums.com/forum/volvo-...k-plugs-12777/

see reviews tab
Bosch Platinum Spark Plug

 

I got the iridium plug for about $6 ea. I went iridium due to their projected longer life span. Just because NGK is manufactured in Japan does not mean they won't work fine in a Volvo. Look at the P.O.S. GM transmission they put in the things. I try to stay away from OEM volvo parts because they are too expensive and their quality seems to have deminished over the years. I'm using Bosch coils though. I've used the multi prong plugs before in other cars but will never use them again. Just my opinion so you are free to use your own judgement. I'll always spend a few extra dollars to ensure I don't have to worry about having to redo anything again for at least another 50K-100K miles. Simply because high mileage vehicle often have one thing after another go bad. So fix it right the first time and forget it is the best way to go.

 

Lunger, I tend to agree with most of what you have said.

I have a GMC pickup with 5.4L and before I changed the factory AC Delco Iridium plugs I did the same research on GM truck forums. What I found was everyone who used anything different than the factory spec AC Iridium plug had poor results- especially the multi prong plugs. They got poor mileage, misfires, etc.... Turns out that this setup uses a resistance measurement across the plug to adjust the ignition. Alternative plugs offered different resistance measurements, fooling the computer and causing ignition problems. For the record, I received a tip that NGK made the AC Delco plugs, and they would work. I used them because they were a few bucks cheaper than the AC plugs, and they have worked OK. However, since I do have some cold start, low speed miss from time to time, I would probably go with the AC plug if I had it to do over again.

I realize this Volvo probably doesn't have as sophisticated an ignition system. But still, I don't want to do this job twice, or waste money on plugs that don't perform at least to factory specs. I have never been a fan of multi-ground electrode plugs, and am surprised Volvo uses them. I have always thought they tend to shroud the spark.

On the other hand, I cant see Volvo using a plug (at time of manufacture) that would not get top performance. That is not to say there is not a plug made today that could do better, which is why I am asking these questions. I dont even know if Iridium plugs existed in 2002 when My car was made.

While you make the comparison with using the GM supplied transmission, I would point out that it is far easier to change plug suppliers or specifications to get the best performance, than to find a transmission to fit your engine/chassis. BTW- didn't Volvo use the GM trans first, and later switch to a Volvo manufactured unit? Is the Volvo unit better?