Replacing Spark Plugs 92 Lumina Z34

[apurgert]

I'm giving my 92 Lumina Z34 (3.4 liter V6) some new spark plugs but I'm having trouble with the last three. They are in the back of the engine and I can't reach them because they are angled towards the back of the car giving little room to get to them. I was using a ratchet with about three extenders on it and a swivel but I can't get them out. Any ideas?

Thanks

[Manny_boy]

You have a few options here. You will probably hear that you can remove your front dogbone and tilt your engine. Nope. 3.1's only. If your 3.4 engine rocks forward when you remove your dogbone, RUN, don't walk, to the nearest parts supplier, for your lower engine mount is shot. For us, the book method is to remove your plenium.

However, if you still have your weatherstripping along the top edge just behind the rear head, removing that may give you some clearance. It wasn't enough for me, so I notched the sheet metal above the rear head to give me enough clearance. The part that I notched is flush with the bulkhead. A cutoff wheel or die grinder will work good for that. Changing my plugs now is about 5 minutes or so.

That sheet metal back there is thin. I've heard of others just bending it up with a pair of water pump pliers, and then bending it back in place once they were done. That's if cutting your sheet metal gives you the willies, and you want to preserve the "integrity" of your car.

Good choice on the 3.4. Plenty of mechanics act like they're scared of them. Ha! I love mine. (Take that with a grain of salt, for I am a gearhead. If you cut me, I bleed 5w30!)

Oh yeah, there's also a spark plug socket with a 15" (approx.) extension and swivel permanently attached. Works well for cars when your spark plugs are in a deep well.

[apurgert]

Thanks Manny_Boy, I just notched it like you did and plugs went in without a hitch. I thought about bending it but then I thought it would weigh less with it notched. Few more engine problems to take care of and it will run again (PCV valve and new air filter. I think I'll just put in a K&N). And I agree with you, 3.4 liter all the way.

[jeffcoslacker]

'Till you pop a timing belt, DOHC boys. Then it is we 3.1's who will be laughing. 170 reliable hp is better than 215 hp hanging off the back of a wrecker...

[Manny_boy]

Jeff's got a good point. Happened to me when I first bought the car. (He's got jokes today, too) Owning a 3.4 is like having a high maintenence girlfriend. isssss gonna cost ya.

I don't wait for 60K now though. I change my T-belt once a year as routine maintenence. Thats a good time to check your idler pullies and your timing actuator. Some say that's overkill and a waste of money, but I drive an AWFUL lot. Plus the added benefit of a fresh belt. Nothing like that off the line bark from a fresh t-belt!

[apurgert]

Yeah I should check it since I bought the car only four months ago and when I showed my uncle the spark plugs it turns out they were original to the car. Would it just be a good idea to get it changed? I've never done it myself is it hard? Or should I just take it to a specialist? Any other things I should look for? Car's got 77,400 (bought it with 76,200) and it seems that I'm 60-70k maintenence. I already replaced the fuel filter, air filter (only had to clean it the person before me had a K&N already in there), spark plugs, new tires, and new muffler (I only have one on because unfortunatly I could not afford to get the other. When I get some more cash I'm just going to replace the whole exhaust). Thanks guys.

[Manny_boy]

Definately check your T-belt. Take off the inspection cover on the front bank of cams (two 8mm bolts) If you find excessive (you're bound to find a few) shavings (looks like hair) inside of the inspection cover or your belt seems smaller than usual, change it asap. The usual reason for the belt snapping, besides high mileage, is worn idler pullies. Over time, the orginal idler pullies get kind of a slope on the outer rim. This allows the belt to ride to one side and "shave" off. The idler pullies (2) are hard plastic, and if you find excessive belt "hairs", thats a good indicator that your idler pullies need to be changed too.

Your tensioner pulley is steel. I've heard that you should change that too, but I didn't and have had no problems. The actuator is the spring that puts tension on the pulley. I would check it too. If the rubber boot that fits over the actuator is torn, replace the actuator. The actuator is oiled internally, and without the boot retaining the oil, is prone to fail.

I gotta be honest, replacing the belt the first time on this car can be a real PITA, but after your first time,I guarantee you'll never have another problem replacing it. Might take you about 2-3 hours your first time to get the timing right. If you need help there, let me know.

Watch out for the rear brakes on the pre '96 w-bodies. The original rear sliders have a tendency to freeze. If your rears have ever been done and the sliders were not cleaned and relubed, you will eventually notice your brakes don't work as well as they used to.

This problem has been corrected, if you purchase new or remanufactured rear calipers, the sliders are brass now, to prevent seizing/galling of the slider/cylinder. (the new brass sliders are blue in color).

Upper lower intake manifold gaskets should be changed at some point if they have not already. The orginals GM provided on most if not all W-bodies are prone to crack and cause vacuum and coolant leaks.


The tube that feeds your heater core, starts at your lower intake. The connector for this tube, actually screws into the lower intake. It is made of cheap pot metal, and over time can leak. (This one really had me buggered, cause you can of course smell the antifreeze, but never see a leak.) That is, until you see the white antifreeze trail on your exhaust manifold x-over. There's a permanent fix for that.

Before your next Spark plug/oil change, get some GM Top Engine Cleaner. Do a search on this forum, you'll find plenty of info on how to use it. It basically cleans your intake and the tops of your valves. But the reside ends up in your oil and the process can foul your plugs- so do it just before.

That's all I can think of right now... Oh, if you haven't purchased the Haynes/chilton manual for this car, spend the $15.00, its well worth it.