mikegbuff

I replaced an ignition coil after the check engine light came on in my 2007 RX350 (60k miles) and all seemed to be well after that. However, after running through 3 tanks of gas, I am down consistently about 6-8% on fuel mileage for city and highway driving. I did not change the spark plug for the bad coil or any of the other plugs because the skip went away and all seemed ok. I didn't see how the bad coil could affect the plug and the code was only saying the coil was bad. Does anyone have any other ideas what could be the issue? Should I change the spark plug for that cylinder or anything else? The book recommends changing the plugs at 120k miles.
Thanks.

lexus114

Did you try resetting the ECM ? That might help.

mikegbuff

Is that something I can do myself? If so, how?

lexus114

The best/safest way is with a scanner/code reader. If you dont have one,or have access to one,you can disconnect the - battery cable for at least 10 minutes. But just to let you know,that is not a preferred method.

mikegbuff

Yeah, I disconnected the battery for a while, which took care of the check engine light, so I would assume that reset the ECM also, is that correct?

lexus114

It probably took care of it then. Did you have to reset your sunroof/window`s after disconnecting the battery ?

mikegbuff

No, I didn't have to do that. There is a sticker under the hood and it also mentions in the manual about having to initialize the windows and sunroof after disconnecting the battery, but I didn't have to do anything, so I didn't really understand how you "initialize" them. I had to replace the battery a couple months ago and didn't have an issue with the windows or sunroof then either. Any idea what the "initialize" means and whether or not I truly reset the ECM since I didn't have to initialize them?

lexus114

I`m sure I`ll get slack for this, But the only true way to reset the ecm properly is to use a scanner, or code reader if you have codes in the system. OBD II is much different than the earlier systems used on automobiles. As far as not having to re-initialize the the window`s/sunroof, I dont know. You got lucky I guess. I had to re do it when I changed my battery last year. I even had to re-do the rear lift gate. Stupid little thing`s allways happen to me,so I`m used to it. For instance, a few month`s ago I ran over a rubber bungie cord and did $1,800.00 worth of damage to the Rx....Only me.

mikegbuff

Two questions for future reference:
1) Can they reset the codes with the scanners at autozone/advance or do you have to go to a dealership or other repair place?
2) How do you reinitialize the windows and sunroof? I couldn't find it in the book.
Thanks for all your help.

lexus114

A) or # 1 as you have it. AZ will usually only reset it if you have a code.

B) #2 It`s in the manual (some where) because I used that reference when I had to re-set mine.

Best advice I can give you is: pick up a scanner when you can. Their not all that expensive any more, and you will be able to help all your friends out when they have Check Engine lights on. (96 and newer) "Impress your friend`s, fun at parties" Michael Keaton Beetle Juice.