JDouble

Guys, I am really at a loss. With so many experienced people on here, I'm hoping maybe somebody has seen this before and can provide some insight.

2007 RX 350

Here is the the story:




Two weeks ago, I'm sitting in my car with the AC running, the car just dies. No warning signs, nothing violent, engine just

dies. AC still running, everything else on. So I cut the car, and everything else off, and try to restart.

The car turns over fine, starts, then immediately dies.
Try again, same issue.
Car sounds goods, nothing sounds off, just dies.

I have an OBD II reader that I keep with me, so I plugged it in, and it read codes P0351-P0356, the Ignition Coil codes. The problem with that is, at least 5 of the 6 Ignition Coils are within 6 Months or so old, along with the plugs (all 6 may be, I simply can't remember if I did the last one).

So I wait 10-15 minutes, clear the codes, and after a few more minutes, it ends up starting and driving fine.

Over the course of the next week, I end up putting around 600 miles on the car, and as I'm driving home, the car dies again. I wrestle it to a side street, and it shows the same codes. except this time it will never restart, and hasn't since.


A couple of thing's:
- If you try to start the car, it dies and you then try to restart the car without turning the switch all the way off, it won't do it.
- I had it towed to my mechanic, how has checked out the the crank position sensor, and it is functioning properly. He can't figure it out either.
- I called a Lexus service center (there is not one here) and while they tried to help, told me they had never heard of anything like this.

Any ideas? Even if I were to believe that new Ignition Coils had failed, they certainly didn't all fail at once, and then allow me to drive flawlessly for 600 miles and then fail again.

Any help is MUCH appreciated, and I will share the results here.


J

tomr51

have you checked all leads/connections are correctly seated?

HtownBlue

Two things:
Massive cylindar failure is usually due to an ECM problem or something like a Cam Position Sensor Or Crank Sensor or some issue that would effect the ignition timing and function of multiple cylinders.

If if it were me I would check the ECM. Next I would check for no shorts in my wiring harnesses. I would also check my fuel pressure. It sounds to me like you likely have an issue with your fuel pump or pressure suddenly dropping and causing massive cylindar shut down.

It it would make sense for the fuel pump to need to shut completely off before being able to reingage and pump fuel again. Thus the key must be turned all the way off if my understanding is correct.

Youve re got to find the potential causes of massive cylindar failure at once. Lots of those reasons so go through them one by one starting with the most likely first.

Lexusdk

Get your mechanic to test and check for spark with each coil. And re-inspect the condition of all the spark plugs. He should've done this from the start. Disconnect the fuel injectors before doing so.

Also have him check the Ignition relay (IGN No2 relay).

JDouble

Thanks for the responses everyone. Couple of updates. To be clear, yes, he did check for spark, I just forgot to include that, and it is good to go on that end.

I changed the ignition switch this evening, thinking that for some reason it was going bad, however no luck. I can however now answer plenty of questions about that, and making room to work up under the dash there.

I have bought the relay, but I couldn't figure out where it was, maybe because it was too dark. Anybody have a diagram of where it is?

I had that about the fuel pump as well, but dismissed it a little when it started every time. But that very well may be it.

Thanks again for all the suggestions, and if anybody has anymore, or any questions, please let me know.


J

numbafree

Please turn on your private message feature, so I can get your email address, to send you something, you probably really want.

Try disconnecting your battery for 15 minutes, to reset the ecu.

Also, is your battery in good condition?

I also vote for bad ecu. You can get a used ecu on fleabay for $250 and up. You read the number off your current one, and match.

ukrkoz

Move ignition coil to a different cylinder. Is the error code following the coil? Then you know for sure it's coil.

Please turn on your private message feature, so I can get your email address, to send you something, you probably really want.

Checking account and pin number also?

numbafree

I was going to send you pdfs from the service manual.

JDouble

Sorry about that. Have been traveling for work. I really appreciate the help. Looks like the ecu (or ecm as Lexus calls it).

JDouble

Okay, so the Ignition Coils are getting no power from the ECM, so that would appear to be the culprit. Is this something I can pull off myself, or does it need to be programmed to the car itself? I would not normally take the car to the dealership, but I've never had issue like this with a car before. Sounds like around a $1500ish repair there.

Has anyone done this themselves, and if so, what advice can you give me? Will the keys need to be programmed to the car again, and is that something I could do?


Thanks so much all the responses.


J

numbafree

You can change out the ECU/ECM yourself. I have. My indy mechanic is a toyota certified mechanic who opened his own shop. He hates me because I always have difficult issues, like electrical. On another toyota, having simliar issues as yours, he told me what to do. Pull your ECM, there is a number on it, match it. If you get a used one on ebay, it's straight forward. Should be the same if you buy brand new. You disconnect the battery, and then swap out the ECM.

You might consider just chatting in person with a toyota mechanic a the dealership. Start with a service manager. I have found them to be very helpful, even if I am not spending a dime.

Good luck.

Lexusdk

Don't forget about the immobilizer, and having to reprogram keys.

JDouble

I guess that's really my question. I've seen a video online for the key learning process, and wondering if that is actually legit, and works. Anyone have any input or have done it themselves?


J

Lexusdk

At this point, the dealership needs to program it. You need to have the Lexus/Toyota software to perform this procedure.