jolomo

Just finished repairing the passenger door lock, so it’s time for the spark plugs. I have 128,000 miles on the original spark plugs. Besides replacing the spark plugs, I am going to perform the IACV service. I have following questions:

1) Any recommendations as which is the best spark for a 2001 RX300?
2) Should the ignition coils be changed? If so, are there any recommendations? I see coils on eBay ranging from $19.99 to over a $100.

Occasionally, the RX does not want to idle when started after it has been driven. But within a minute will start idling ok. Always starts and idles from a cold start.

Thanks, John

hypervish

The idle issue should be resolved once you clean the IACV.

1) Stick with OEM, so either Denso SK20R11 or NGK Iridium.
2) No. If an ignition coil fails it will trigger a CEL, no need to spend extra money.

IndyRX300

Check out advance auto parts for the plugs. I got mine dirt cheap. Use coupon codes visa or retmenot123. Code Big30 will take $30 off of orders $75 or more. Just mess around with the codes for the best savings. You can use more than one.

salimshah

I would wait for a fail on ignition coil [cel + code] will tell you ... other than an obvious loss of power. Recommended interval to replace spark plugs at 110k miles.

Salim

Rodney79

John,
Just replaced my plugs with NGK GP Platinum - I like them and have used them on several different vehicles. The three plugs in the rear are a bear to remove, but there are great tutorials on this site and advice on this site about that chore - it can be done, but it is not easy.

I would not replace the ignition coils unless they are malfunctioning.

Regarding the idling problem, I had a similar problem a year ago - vehicle would start, but would not idle and would stall unless you kept your foot on the gas. This problem was intermittent - some days there was no problem at all. The cause was a dirty air-idle valve. Repair shop wanted $500 to replace the valve. I removed it, cleaned it with carburetor cleaner, and reinstalled it - car runs like a top now. It took about 2 hours to remove only because I did not have the right tools and had never done it before.

Rodney

jolomo

Thanks Rodney,
I installed the Denso SK20R11, cleaned the throttle body including the IACV, and replaced the PCV valve. The old plugs were NGK, they looked good for 128,000 miles and showed no signs of oil fouling, nice light brown color. The throttle body and IACV were really black inside, especially on the IACV side. I wonder what causes that?

Haven't driven it much but the RX seems to idle fine but appears to idle a little higher than before. I just finished getting the RX back together Saturday afternoon.
Thanks for all your help,
John