Valve cover gasket/coil pack replacement (1 Viewer)

[Moxlandia]

Hello all, first post on the forum. Bought my 99 cruiser 2 years ago and I love it. I appreciate this forum as it has been a HUGE help.

The valve gaskets have been leaking a very small amount until recently. I’ve ordered all the parts and plan to replace. However last week it started to sputter/misfire at acceleration. I’ve read here that this is probably a coil pack(s) since a leaking gasket can cause damage to them.

question: I’m trying to figure out the order in which to tackle these jobs. I plan to first replace the gaskets with a kit from Witts End. But not knowing if or what coils are bad, should I drive it to the auto parts store after gasket replacement to let them run the codes and just replace the bad one(s) or possibly replace all? It has over 200,000 miles on it and the previous owner only did maintenance when something broke. I will be replacing all spark plugs as well.
Thanks for the help!
Mox

 

[3_puppies]

MHO would be just to change all the coil packs and plugs at the same time and be good for a long, long time

 

[JunkCrzr89]

MHO would be just to change all the coil packs and plugs at the same time and be good for a long, long time

x2 - I agree. Also make sure you get new spark plug tube seals for the valve cover, a new PCV valve and grommet, and a tube of FIPG.

 

[94SRUNNER]

x2 - I agree. Also make sure you get new spark plug tube seals for the valve cover, a new PCV valve and grommet, and a tube of FIPG.

x3. Additionally, make sure you get the torque on the spark plugs good (no anti-seize on the threads). The plugs in the 2UZ have a track record of loosening over time. The FSM calls for 13ft-lbs, but the consensus seems to be that around 16-17ft-lbs keeps the plugs where they should be. Then periodically checking the torque (I check them every oil change)

Ticking time bomb TICK TICK TICK: Spark plugs Alert Alert Alert!

TICK TICK TICK POP POP POP is a ticking time bomb, often mistaken as exhaust manifold crack or gasket leak leak. ALERT, ALERT, ALERT: Spark plugs are working themselves loose. "Walking Out" Then blowing out of head, taking their female threads of head with them! Very damaging! You think TICK...

forum.ih8mud.com

 

[thabruiser]

Breaking ranks with consensus. In my humble opinion, I would find out which cylinder is misfiring. It is possible and likely that if you have a misfire, it is a coil pack. But I have done several of these valve cover gaskets and discovered the spark plug tube was full of oil, causing the misfire. I am of the mindset that you should not replace something that is not broken. Many times we inadvertently introduce a problem into the system that wasn't broken, usually due to sub-par replacement components (i.e. aftermarket). If you replace everything with Toyota parts bought at a dealer or from a dealer-sourced supplier, you will be fine 99.9% of the time. But IMHO why replace 8 coil packs when it is only one causing the issue? It And it is also possible that it is just a worn-out spark plug. I love new parts, but I also like to know that I know why the thing broke, and what I did fixed it. Hope this helps!