QuestionHaving taken note of your comments, I feel sure like me the local mechanic had never heard of two different types of plugs used by Lexus. I really think it was just the hardware ( be it only plastic ) surrounding/covering the 4 on the side opposite to the battery, which needs removing! I will go look some more on the links you recommend. I could be seeing problems where you don't, if you know what I mean. The plugs I intend to fit are platinum tipped is all I know, ($20 each).
Thanks again,
Ian
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The text above is a follow-up to ...
-----Question-----
Hello,
I am OK with basic tasks on cars, but was a bit shocked when I came to changing the spark plugs on my 1993, LS400.
Before I retired it was serviced by the main dealer (not cheap)but the last time was by a local garage. On the bill I noticed that they had only changed 4 of the plugs but put this down to a typing error, now I think maybe they were telling the truth! If you can help me with any advice it would be great, or where I can download a manual (PDF) online.
Thanks,
Ian Whitley
-----Answer-----
LoL! No problem. We still see this alot. See there are two basic parts makers in Japan for ignition & electronics crap. NGK (honda), and Nippon -Denso (Toyota) (Seen ND on your car, now just Denso. Denso is the world's largest vehicle parts manufactuere by a wide margin by the way.)
Anyways... Japanese ignition systems are ***very*** sensative to plug types. They like very low resistance plugs. They all specify Denso, and NGK plugs regardless of OEM for one reason. Every other plug will run like dogshit within a year if you take them out & compaire them to the specified Japanese plugs.
Now that you know that, I'll explain why they changed 4 plugs.
What happened, is that during 1uz-fe production in the first full generation (89-94). The Toyota plant assembling the engines sorta ran low on Denso spark plugs for whatever reason. So the v8's have one bank of Denso plugs & one bank of NGK plugs from the factory.
Non-Toyota / Lexus mechanics generally see one bank as original pugs & the other as having been changed. So they are prone to changing only one bank of plugs because people are cheap & don't like paying for other things. ;)
Whew!
I digress. They probably put Bosch, or Autolite plugs in there. You'll want those out anyways Ian. ;)
I'm not sure of anywhere to download the factory service manual.
Ask on www.lextreme.com's forum. Maybe try www.clublexus.com also.
If all else fails, Toyota's material network is techinfo.toyota.com
$10 will get you access to download about any information they have on anything they've produced bound for North America since 1990. It's alot of clicking, but if you piece it all together you've got *the* factory service manuals. They even have the training manual for T-Ten. (Toyota's technition training program.)
AnswerThe engine covers? They're just normally held on with afew 10mm's. It shouldn't take a mechanic to remove them to get to the plug wires & plugs. ;)
Take those plugs back. They're bullshit & you're wasting your money.
The pricing goes for both NGK & Denso:
Copper $1.50-2usd
Platinum $2-3usd
Laser cut platinum $4.50-6usd
First generation Iriduim $9usd
Current generation Iriduim $9-11.50usd
You're screwing yourself bigtime on far overpriced plugs that are not going to have a good lifespan. Please trust me. ;)
