With some time on my hands now, I'm going to be tackling some things on my '98 LC with 250k miles that I've been meaning to get to. I've noticed my driver's side valve cover gasket is seeping oil, which got me thinking about doing my ignition coils and plugs while I'm in there. First off, would I be wise to do both of my valve cover gaskets even though my passenger side isn't leaking? Secondly, while the major maintenance has been documented on my LC, I have no records of when coils and plugs were changed last. Periodically, especially on colder mornings, the truck has stalled out when shifting to reverse (I'm assuming due to the RPM drop) if I didn't allow it to completely warm up. It can also tend to be a tad rough at idle from time to time. This sounds like a bad coil to me, but due to the unknown maintenance history of the coils and plugs, would I be wise to change out all 8 coils and plugs? Or is the common practice to narrow down the bad coil and just replace as needed. Any input will help, thanks!
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Trunk Monkey
Moderator
^that. Replacing all 8 coils is spendier PM than I can swing. Start with simpler maintenance items - clean the MAF and throttle body.
careful tightening them down. look at the torque spec. you can't torque them properly with old gaskets but basically re snug them. wrist tight is too much. you could crack the valve cover.
it will buy you time. I did it on my tacoma nearly 2 years ago and it hasn't returned yet. but I'll tackle it one day. that said, this is the perfect time to do the job right if you got the motivation.
coils are good until they're bad. thats the conventional wisdom anyway.
it will buy you time. I did it on my tacoma nearly 2 years ago and it hasn't returned yet. but I'll tackle it one day. that said, this is the perfect time to do the job right if you got the motivation.
coils are good until they're bad. thats the conventional wisdom anyway.
I just did new coils/plugs and cleaned throttle body this week and happy I did. I wasn't having any major issues with cold starts, but a little uneven idle. Motor pulls a little better between 2-3k now and idle issue is gone. Expensive PM but the motor seems happier for it.
JunkCrzr89
Competent Ignoramoose
If you’re replacing DS VC gasket, might as well replace the PS, too, which is easier than DS. As others above noted, replace all the plugs (inexpensive) but inspect coils and replace coils as needed. Keep in mind that you can also buy a reboot kit for the coils, which can extend their operating life (and your money). Part #: Denso 671-8184
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Do NOT buy cheap coils. They often work at first, but then cause issues later. Sometimes quite quickly. If they are less than about $60 a coil, they are probably fake.
- Thread starter
- #8
If it were any other time, I would definitely just tighten them up and keep an eye on it. But considering the gaskets are pretty cheap and my time is free (and I've got plenty of it these days), I'll likely replace the gaskets. Thanks for the input!
- Thread starter
- #9
Awesome, thanks for this.
- Thread starter
- #10
The previous owner told me he replaced a coil within the last few months of his ownership. Wasn't able to remember which one he replaced, but the coils he bought came in packs of 2 and he gave me the remaining one and it's a cheapie. I'll definitely be going in there and finding the one he replaced as well as any others that are bad and replacing with Denso coils. Thanks!
Here's an easy way to spot a new coil
JunkCrzr89
Competent Ignoramoose
OEM Denso coil can be had for $48-50 now.
The best price I had found was usually JEGs with a coupon code. Where did you find them for under $50? That would be great.
I bought mine on Rock Auto and had them all done at once. Also had the injectors flushed and cleaned the throttle body. Maybe it was overkill, but now I know I don't have to worry about it for a long time and the rig seems to be happy.
JunkCrzr89
Competent Ignoramoose
RockAuto
JunkCrzr89
Competent Ignoramoose
Definitely not overkill to clean injectors and TB. Arguably critical to a happy running 2uz.
We cannot order from Rock Auto in Denver anymore
Stupid tax collecting laws.Thanks for the help
JunkCrzr89
Competent Ignoramoose
Communists. Next best is Amazon for $53:We cannot order from Rock Auto in Denver anymore
Thanks for the help
Amazon product ASIN B002Y37M0W
With free shipping, might actually come out better than RockAuto!
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By the way, I made the mistake of ordering a separate boot set, which was unnecessary as the new coils came with new boots.
