2007 Rx350 Spark Plugs & Ignition Coil Replacement

[RX350Girl]

My CEL & VSC came on & I determined it wasn't an issue with the gas cap. Went to AutoZone & diagnostic threw 7 codes. Need to replace all 6 spark plugs & 1 ignition coil. I've only had this car since July, so I haven't gotten my hands dirty with it yet or even looked under the hood for that matter. Too busy to be crazy into my cars now. Anyway, my question is will I be able to change all the spark plugs myself, or will I need to take out the intake to get to some of them? Also, will I be able to easily replace the ignition coil myself?

Thanks!

[RX400h]

As far as the sparkplugs go.......I'm not sure if this Canadian version is exactly like yours, but one thing is for sure about it - it is not exactly a quick procedure.

http://www.clublexus.com/forums/rx-second-generation/609747-lexus-rx350-3-5l-nap-made-in-canada-2008-spark-plug-change.html

...not sure about the coils, though.

By the way, how many miles are on your RX?

[RX350Girl]

right now there is a little under 87,000 on it....I hope mine is not the same as the one you linked to lol...definitely don't have the time to do it myself if that's the case...more money out the window womp womp. In your opinion: If I need to replace one ignition coil do you think I should just replace them all at this point considering the mileage & the car has not yet had a tune up? All other routine services have been done on the car according to the carfax I was given when I purchased it.

[lenore]

I would only replace the bad coil. As for the plugs they generally last an easy 125k miles. I would go after the bad coil and stop at that point. I seriously doubt the plugs are bad.

[RX350Girl]

diagnostic came back with missfire codes for all 6 spark plugs...so in that case should i pursue lexus to replace? Factory warranty is done.

[lenore]

That is weird, would love to see what codes you have. Missfiring on all is not usual. That is why We like to see all codes. The code will tell us which coil, if it is a front of engine one it is a piece of cake to replace, the rears are on the other hand not easy....Replacing that coil, and reset the codes and see what happens. As for plugs, just don't believe it. Unless somebody else changed the plugs and put something other than iridium Denso or NGK plugs in. That is another story. Never use plugs other than the iridium NGK or Denso. They last a long time. Mine have 144k miles and they look great.

[RX350Girl]

I'm going to have another place run it again & see if the same thing comes up again. They didn't give me the print out of the codes when I went the other day. I believe the ones in the car currently are iridium

[lenore]

The original plugs on all RX's were iridium...They just cannot be matched. Good luck with the codes, once we see them we can tell you which way to go. Example of bad coil would be P0301 code which would be cylinder 1.. When there is a misfire, other codes crop up that don't necessarily indicate the problem. We await your troubleshooting.

[RX350Girl]

Thanks!

[RX400h]

The original plugs on all RX's were iridium...They just cannot be matched. Good luck with the codes, once we see them we can tell you which way to go. Example of bad coil would be P0301 code which would be cylinder 1.. When there is a misfire, other codes crop up that don't necessarily indicate the problem. We await your troubleshooting.

...cannot be matched? Do you mean mismatched or replaced with other types?

I, too think it is unusual for the plugs to be bad at 87,000 miles.

[als47]

I agree with the previous comments. Get the codes. The front ignition coils (cylinders 02, 04, 06) are very easy to get to. The rear ones (01, 03, 05) are unfortunately a pain! Maybe you're lucky. I have the same model, with about 80K miles in it, I have had to replace 2 front ignition coils, but not at the same time; they are about $110-120 a piece.

As to the spark plugs, I have not had any problem so far on my car, and I doubt that all of them would go bad at the same time.

[lenore]

What I meant was the plugs cannot be matched for their quality...Best Plug I have ever used in 50 years.

[RX350Girl]

Sorry for the very long delay. I just ended up driving my other car until I had time to deal with the Lexus. So I went back to a different AutoZone to get the codes & that time only 2 codes came up. P0300 & P0356. Ignition coil 6 was bad, which lucky for me was an easy fix. All warning lights went off after driving about 200 miles. Thanks for all the input guys!

[sam2004]

Cannot believe your spark plugs and a coil is bad. I am driving a 2004 Rx330 with 332,000 Km. Never replaced the plugs. Motor still runs smooth. Never had ant problem with emission. Please check at another dealership.

[RX350Girl]

Sam...the plugs were fine. It was a bad ignition coil. See my post above :)

[Love My Lexy!]

On 5/9/2014 at 10:19 AM, lenore said:

That is weird, would love to see what codes you have. Missfiring on all is not usual. That is why We like to see all codes. The code will tell us which coil, if it is a front of engine one it is a piece of cake to replace, the rears are on the other hand not easy....Replacing that coil, and reset the codes and see what happens. As for plugs, just don't believe it. Unless somebody else changed the plugs and put something other than iridium Denso or NGK plugs in. That is another story. Never use plugs other than the iridium NGK or Denso. They last a long time. Mine have 144k miles and they look great.

Mine to did the same thing today all misfires!

[Love My Lexy!]

On 6/19/2014 at 9:01 AM, RX350Girl said:

Sam...the plugs were fine. It was a bad ignition coil. See my post above :)

Did you have like a rumble feel when you where going down the road?

[Mommalud]

I'm having the same problem...CEL and VSC light both on. Codes say all 6 misfiring. I am hesitant to give to mechanic he wants to replace all 6 and plugs. I have 116,000 miles on my 2007 RX350. Should I start with the spark plugs first?

 

[Love My Lexy!]

No! It more than likely the ignition coil. Auto zone shot out the same thing on mine and they said computer was bad...etc But I had a code P0301 which was ignition coil one was bad. Did mine 2 weeks ago no problems since had to have the light cut off but it has not returned yet have drove over 1500 miles since! It only cost 75.00 for the coil.

[als47]

Very unlikely for all coils to go bad at the same time. Have it rechecked. I replaced twice a coil, luckily both times they were in the front bank of cylinders. Never had a problem since, about 3 or 4 years.

[Mommalud]

Thanks everyone. I'm having it looked at today. I will let you know the outcome.