DOHC rear plugs, easy solution

[Psych0matt]

So after some fidgeting around I finally found the perfect combo to get the rear plugs out. This can be done without removing anythings, without rocking the engine, without cutting the firewall lip. I did all three of my rear plugs in under 15 minutes, and the hardest part was just getting the wires back in because of the goofy plastic tubey thingy that they go in.

Here's what you'll need:
1/2" socket wrench
1/2" 5" extension



1/2" to 3/8" socket adaptor


3/8" universal joint



3/8" 3" extension


3/8" extension connected to your spark plug socket




Here's what you do:

First remove the plug wire. You may have to use a little bit of force and some twisting and wiggling, but it can be done. With the socket and first extension already connected, lower it into the plug hole enough so that you can still hold it with one hand (and not drop it in). Once you have it down far enough for the second 3" extension to be down past the lip, pop it on to the first extension. Drop it a little further so you can get the U joint on. At this point you should be able to get the socket most of the way down onto the plug. You should be able to now pop the adaptor on, and then the 5" extension. Once you do this, it's pretty self explanatory. You'll have to loosen the plug and then reverse the process (removing each section), but then you should have your plug out, and installation of the new plug is reverse. Again, took me all of 15 minutes to do all three, and half that time was probably fighting to get the wires back on

[94 olds vert]

Good idea, if you don't want to rock the engine. I just removed my dog bone and rocked the engine, didn't take me that long either.

[GOT2B GM]

Or, disconnect the dogbone, and back the car up onto ramps, shut it off, and put it in park or 1st gear allowing the weight of the car to roll the engine forward.

Then you don't need a universal joint and the spark plug boots are much easier to get in.

Also taping your socket / extensions together is a good idea so your socket doesn't fall off the extension when down there.

[Psych0matt]

I know, I know, there are other methods! For me this is by far the easiest. I don't want to to use ramps to do spark plugs though, or disconnect the dogbone if I don't have to. I kinda did this writeup just so in a year or whenever I do this again, I don't have to do any of that, and I don't have to scratch my head trying to remember! Just seemed like a good alternative for someone who doesn't like taking crap apart to do something that shouldn't require taking crap apart

[fastbird232]

I know, I know, there are other methods! For me this is by far the easiest. I don't want to to use ramps to do spark plugs though, or disconnect the dogbone if I don't have to. I kinda did this writeup just so in a year or whenever I do this again, I don't have to do any of that, and I don't have to scratch my head trying to remember! Just seemed like a good alternative for someone who doesn't like taking crap apart to do something that shouldn't require taking crap apart

You've pretty much nailed it. This is how I did my LQ1 plugs, and there's really nothing to it.

[Red Nightmare]

ON my LQ1, I have never had any real problems getting the back plugs out. tight squeeze yes but seems just enough room that with the right extensions you can get to them. Sometimes I rock the engine but even that is not really necessary. Is my 94 GTP set up in some fashion that is not usual?

For rocking it, I just rock the car and apply the park brake when it is forward.

[carkhz316]

Cut the half-circle slices out of the weatherstrip flange on the front of the cowl. Works like a charm and can be covered back up with the weatherstripping. Tis what I did on my '92 when I had it at school. I then did my engine-bay jamming/ painting, and it looks like they're supposed to be cut like that. No U-joints or adapters required as it's a straight shot at the plugs then. Just my .02

[Psych0matt]

Yeah, all good options, not arguing that, but again my main issue was the concept of why should you have to modify something that you should be able to do without modifying? Just my opinion on what's best/easiest for me

[virtuetovice]

1. Remove dash
2. Put 3 holes in firewall
3. Remove plugs
4. Install new plugs
5. ?????????????
6. PROFIT

[94 olds vert]

5. ????????????? = Install DIS and UB3.

[99screaminregal]

Thas' how I did mine. Just took the weather stripping off and went to town on it.

[Steel Head]

Yes very easy using the right socket extensions and swivel, designers should really have some knowledge in mechanics so they can design cars better. Something as easy as changing spark plugs should not be so difficult IMO

[95pghvert]

im having a hell of a time with the rear plug wires on my cutty...i got her back today and changed them but now it runs and spits n pukes, Iam thinking i didnt get the plug wires all the way down on the plug....So basically you disconnect the dog bone and it will rock forwards? Iam afraid of doing that but is it just that simple ( im no where near a mechanic is why i ask) i just like trying things first before i pay someone to do it

[GOT2B GM]

Unbolt the dogbone and you can pull it forward, try a ratchet strap, or park it facing downhill so the weight of the car pushes on the parking pin in the trans and rocks it forward. You won't hurt the car.

[Psych0matt]

i once connected a strap to my brothers jeep and then threw the jeep into neutral and let the weight pull the engine a bit. Worked like a charm