I have a 98 GS400 and I wanted to change my own spark plugs to save some money. I was pretty confident after what I've searched and read in the forums. Here is what happened.

First of all, I read over BananaGS's tutorial on his website on changing spark plugs.
- I followed every step....removed the intake, engine cover, etc..
- Unplugged all 8 connections
- Unscrew the 10mm bolts for the boot plugs
- Pulled out the boot plugs

Now here is where the trouble started. I tried to remove the spark plugs but didn't get anywhere.
Which way do I turn to get the plugs out? counterclock wise? I've tried to turn it, but it didn't budge. I didn't want to break the plugs so I didn't venture any further. Another big problem was that the socket got stuck in the spark plug chamber a couple times and kinda freaked me out when I couldn't get it out. It took some patience but at least I got the sockets out of the engine block. My question is which way do I turn to get the spark plugs out and is there anything out there that I can use to make it easier to get these things out? I just gave up after a while and put everything back together.

Also, I had 2 engine code errors and they were P0171 and P0300. Can anyone tell me what these are?

 

The plugs follow the righty tighty, lefty loosy rule. That is you turn them counterclockwise to get them out. They're stuck because the last person turned them in too hard and/or forgot to use antiseize on the threads.

Before you get out your breaker bar, try these things:

Reattach the plug wires and warm the engine. Then try again. It's possible that the different expansion rate of the plug base and head will help you out.

If that doesn't work, then try again with the engine at operating temp. This will make it a little uncomfortable to work around but it might help.

Finally, put a small amount of penetrating oil arount the base of the plugs so it will run down and around the threads, Leave that in there overnight. Then try again.

As a last resort you can try more torque but you may break a plug and they're real hard to get out after that. I'd suggest taking it to a pro.

George

 

No offense, but if you don't even know which way to turn, you really shouldn't be doing this. Leave it to a pro.

Also, use compressed air to clean the area around spark plugs before proceeding. This is to prevent dust/debris from falling into the cylinders.

 

Take it to a pro!
It sounds that you will save more money that way.
Also, if your socket gets stuck in the chambers (BTW, it's the heads and not the block), you are not using the right socket fo rthe job.
Good luck.

 

To elaborate on what Rice said, if the socket got stuck, that's a sign of the socket being slightly too loose and beginning to round the 6 corners of the spark plug. If you're gonna try again yourself on a hot engine be sure to use a socket that feels tight and securely grabs all 6 sides of the plug- you don't wanna round the heads.