MrApex

So the dreaded check engine light came on. Ran over to AutoZone
and borrowed the code reader. Misfire code on #1 and #2.
p0300, p0301, p0302.

Symptoms were a very rough idle, but the car was still driveable.

Pretty sure I had bad coils. Talked to my Mazda Master Tech brother...
he said coils do have a tendency to die out. I went ahead and ordered 3 new
coils since the rears were difficult to get to.

Toyota moved to a new PN 90080-19016 I paid $90 each.
I believe there is a TSB on this issue.

Well I had to dismantle alot to get to the back plugs!
I guess I had a lot of practice with tight spaces on my MR2 Turbo.
The RX300 sure rivaled it in difficult of removing the intake manifold.

1 ground strap, 2 stay brackets, and 2 hard pipe bolts very hidden
on the backside of the manifold. Lots of fun!

I removed all plugs and inspected. Besides being sooty/dirty/slightly oily -- they
were fine. Once I replaced the #1 and #2 coils -- it idled just fine and the
check engine light went away.

Total R&R time for me was around 6 hours. Fun stuff. Good luck to all those
who have to do the same job!

Lexmex

My uncle was able to put in my TorqueMaster plugs without removing the throttle body. Sure it was a pain but when he heard everyone else was doing it that way, he saw it as as challenge. We did have to take off the accelerator cable and the tube, a hose (PCV) and one other thing on the left side to get to the rear plugs. Putting in a new ignition coil the rear area is a lot easier than changing those plugs.

Grumpa72

What items did you replace? Sorry, I haven't been following your thread and don't know what PN 90080-19016 is? Coil? Spark plugs?

Gary

Tammy

If not mistaken, the part number refers to the coils that fit atop the spark plug.. But were the plugs replaced while in the area? Appearently not.

MrApex

I typed up the post in haste. I did not replace the plugs.
The iridium plugs hardly wear out...

AMN

I have P0302 code. I want to check a coil and a plug on a cylinder #2.
Could you tell me how they marked cylinders? what cylinder is #1, #2...?
maybe someone can attach a picture?
By the way, thanks to Lexmex and Meetya for the help: I had P0171 code. mechanic charged $160 to fix it. in two months CEL was up again with the same code. and I fixed that for free in one minute by cleaning MAF with electronic cleaner. Thanks guys!

thomas1

Facing the engine from the front of the car, 1,3,5 is on the firewall side of the engine from left to right. 2,4,6 are the cylinders from left to right on the engine closest to you. left above is the passenger side and right is the drivers side when facing the engine.

salimshah

my 2c:

One must look at the age of the part that is failing and if there are multiple parts, one should weigh replacing all of them.

For the case above, if 2-3 coil-packs failed, I would have replaced all six. Most probably the others came from the same batch and if 2/6 failed, the others would most likely fail shortly. [pessimistic attitude, but why go through the hassle again and again]

Salim

Lexmex

This is #2, I remember where cylinders are by thinking like I got a stick shift car and where the gears are on the stick.

AMN

thanks to everyone!
now it's my turn to share an experience. and ask another question.
with P0302/P0302 code I switched ignition coils on 2-nd and 4-th cylinders. OBD showed P0302/P0304. I supposed P0302 came with computer memory. I purchased new ignition coil 90080-19016 (original was 90919-02234) at Toyota dealership and install on 4-th cylinder. codes disappeared immediately. I ran the engine for 10 min, then drove 5 miles. everything looks ok now.
the only question to professionals is: with codes OBD had red lid up. now (without codes) it has orange lid up. is that normal? should it be green?

Lexmex

AMN,

Not sure I have ever heard of that. If you have a CEL on the dash, then there should be an accompanying code. Without any codes, there should be no CEL on the dash.

Only other time you can get no CEL on the dash and have codes is with pending codes that eventually can turn into a non-pending code and cause a light on the dash.

salimshah

Are the orange and red, lights on the OBDII reader? If you can share the make and model of the reader, it might shed some more light.

Salim

pinoyballa

i had multiple misfires too... it was due to a bad ignition coil

AMN

attached is a picture of OBDII I used. probably my description was not correct. after I replaced a coil and erased codes there is no CEL on a car dash board. OBDII has 3 lights: green (all systems are OK), red (and OBD shows a code/codes) and yellow/orange (no codes, but something is not right: there are pending codes, or OBD has not finished monitoring of some systems). in my case orange light is on and there is no pending code. some icons are still blinking (catalist monitor, evaporate system monitor, oxygen sensor monitor, oxygen sensor heater monitor). I supposed they should stop blinking in short time, but they are still blinking after short ride but no codes appear. tomorrow I will drive for an hour and see what happened. I let you know. thanks to all.

Lexmex

Ah, I know what you are talking about. Those are readiness monitors. That is something they check in some areas on emissions tests, usually OBD2 tests. My home state of Florida doesn't have that nor even here locally in Mexico, but some places, I think New Jersey, check for that.

For the readiness monitors to be okay, you just have to keep driving, usually an hour or so of straight driving before they reset themselves.

My uncle has a more advanced Actron OBD2 scanner I bought him and it notes these things and I notice it will have an issue if I have just disconnected and reconnected the battery.