Removing spark plugs
 

Have two '86 944s - just purchased spark plugs. The new ones I purchased take a 5/8 socket. Put the same socket on the ones in the car and it doesn't fit??? I've done plugs in the past for 944s and everything went easy. What socket does everyone use to take out their plugs? Sometimes the easy things become hard for some reason.

The ones in the 944s are 13/16. The 5/8 ones you have may not be the right flavor. I'd verify it before installing them.

Your toolkit should have the tool for the sparkplug included.

Thanks guys.

I was given NGK 3517 iridium plugs. Aren't these 944 plugs?

No, NGK 3517 are BKR5EZ

You want:

NGK (6637) BPR6EIX Iridium
Autolite XP63 Iridium XP
Champion RN8WYPB3 (9804) Iridium
Denso (5305) IW16 Iridium
Denso (4708) IW16TT Iridium TT

I guess that I'm really old school... I still use Bosch WR8DC.

I had a problem with a 944 turbo some years ago that would not boost at all, but would idle just fine. Tried everything, DME, KLR, smoke test, plug wires, etc. Turned out it was the Bosch Platinum plugs... they were worn, but you could not look at them and tell that, they looked just like new ones. At least with the copper plugs you could see the worn out plugs.

Thanks for the info. They did, indeed, give me the wrong plugs. I'm going with the Bosch coppers like you say.

The Bosch always work fine for me; I replace them every 10k or so with no issues.

fwiw I've never found a modern plug that performs as well as the stock Bosch WR8DC and I've given a few of them a chance.

Bosch plugs no 1 on import cars especially made in Germany.ac delco ,champion,autolite are designed primarily for autos made by US manufactures.
You already had the answer from another member.Bosch.NGK mostly japanese
import /cars& motorcycles.
In trade school we had a test on a engine that didn't run.Brand new everything.plugs wires cap rotor coil timing dead on fuel delivery 100% compression excellent new engine .would spin over but wouldn't start.
Checked everything over 100 times.
Ends up bad electrodes in new plugs right out of the box.
Plugs wouldn't fire.
The rest of that day we spent learning a lot about spark plug manufactures.Bosch was no 1 in the 70s and still is for porshe.

You replace them every 10k miles? I've run a set of WR7DC's in my 87 for 100K miles and they were still good when I decided to replace them.

NGK BPR6ES is what my (excellent and very useful, thank you!) Haynes manual suggests so that's what I've always used.
13/16 hex. Copper.

The maintenance schedule calls for 12k replacement intervals but I'm bit of a freak. Don't ask me how often I change the oil...

The 944 replacement schedule for replacing spark plugs is every 12k miles? Wow. That seems tremendously overkill.

The ideological subversion that something more expensive is better is a fail in this case....like buy more and save.

Copper core resistor plugs are two bucks or so.

I thought they always preach now that iridium plugs are better in every way than plugs of yesteryear. I suppose not for every vehicle.

I think the extended life plugs came into play because of accessibility...think Aerostar van or any modern Subaru with 2" between the head and the frame rails.

My specs call for the multiple electrode Bosch and they exhibit better cold start characteristics over NGK plugs or the single electrode Bosch.

They last longer but they don't make the spark more sparky or anything like that. I generally use Bosch coppers as I take them out for inspection (or a timing belt, etc.) often enough that a long life is not a big plus.

I own one of each of those vehicles :D

My DOHC Subaru has so little clearance (not even 2") between the valve cover and frame rail that you have to undo the driver side engine mount and jack up the engine 2-3" on that side to get access for the DS rear spark plug...that was a lot of fun.

Subaru spec's some crazy NGK Iridium in that motor because of the difficulty in doing the job and rates them as 60,000 mile plugs...at $50/set of 4 :eek:

And the Aerostar...to get to the rear plugs you have to be INSIDE the car and remove an access panel under the carpet!

The 8v 944 spark plugs are stupid easy to change but I'm only on my 3rd set since pulling the car from the dirt in 2005.