Jump to content


I'm lost...please help?


Recommended Posts

I'm new to this forum stuff, so bear with me please.

 

I have a lexus problem, and I really could use some help. If I need to post this elsewhere, please let me know.
I have an RX350 2007 model that cranks but no start. The codes all point to 6 bad ignition coils, but I find this hard to believe. Also, there was a code for crankshaft sensor, but I replaced it, and that code is gone. Now I get a code for camshaft sensor, P0340, so I pulled the plenum or intake, and swapped the difficult one that's supposedly bad to a more easily accessible location. The code changed from 0340, to tell me bank 2 sensor A. While I had the intake off I pulled the spark plugs, to clean and check, and I found one had a bent electrode. No scars or obvious signs of impact, so I regapped it and moved it to a more easily accessible spot.
My question is how to determine if there is a problem with timing chain/belt before I shell out money for new sensors. If I know the chain/belt is ok, then I will proceed and likely replace all 4 sensors before I put the wipers back on.
Any help would be greatly appreciated.

Link to comment
Share on other sites

Wow, it's cold here...

 

Seriously can anyone point me to another forum, or tell me how to get help please?

 

Thanks

Link to comment
Share on other sites

I would check all grounds wires and the charging system, battery, etc. Too early to condemn ecu's but I would bet all those codes are due to something that’s not related to the codes listed above, and you have a short or a ground somewhere 

  • Like 1
Link to comment
Share on other sites

Thanks. I didn't want to start out saying that I suspect the ECU, but that's my belief. Also, I don't hear the fuel pump. I removed the seat and used a jump wire and it does work. I've checked all fuses, and verified that the circuits are getting power. Can I unplug a coil, and with the key on probe the coil harness for power? 

Again I thank you for your input. I will look for grounds when the rain stops. I do hope that the alternator isn't the culprit ( sending dirty power, or leaking A/C into the system). It's a serious pain to remove...again. It had to come off, along with the compressor to replace the crank sensor.

Link to comment
Share on other sites

I disconnected a coil, turned the ignition switch on, and probed the coil connector and only get 5 volts.

Shouldn't it be 12?

Link to comment
Share on other sites

14 hours ago, dcfish said:

This will help : Be patient, There are very talented members here.

Are they on vacation this week?

 

just kidding, I'm stressed. please accept my apology

= )~

 

  • Like 1
Link to comment
Share on other sites

9 hours ago, JusB said:

I disconnected a coil, turned the ignition switch on, and probed the coil connector and only get 5 volts.

Shouldn't it be 12?

No. Could have varying voltages, duty cycles, etc. 1 faulty coil won’t stop your engine from turning over.

Could be the Fuel pump, unless you feel like rigging up a 12v power supply and the appropriate connections I don’t feel like that matters  

check the fuel pressure at the rail if you have a shrader valve. If not, you can always pull one the linee off any injector too and see if fuel comes out. That should help in the process of elimination 

  • Like 1
Link to comment
Share on other sites

Thanks I will try that in the am.  It just feels odd that coils AND fuel pump seem to be not getting powered. Makes me think ECU, but I have no way of testing this.

 

Thanks again for taking the time to help. I appreciate it.

  • Like 1
Link to comment
Share on other sites

33 minutes ago, JusB said:

Thanks I will try that in the am.  It just feels odd that coils AND fuel pump seem to be not getting powered. Makes me think ECU, but I have no way of testing this.

 

Thanks again for taking the time to help. I appreciate it.

Good luck.
 

Agreed. Honestly when I read your original post my mind went “uh-oh” but there are some troubleshooting methods to verify first.
 

A motor is a just an air pump: it needs 3 things. Gas, spark, and air. 

 

 

 

Link to comment
Share on other sites

Can anyone here, or should I say will anyone here give me some advice?
I suspect that this is a bad ECU. Likely a coil shorted and fried it. This means I need ECU and 6 coils.
That's a heap of cash to waste, with no guarantee that it solves the issue.
So, I was wondering...since I don't have access to sophisticated test equipment, can I unplug all 6 coils, clear the codes, and see what codes pop
then? If there is 12 volts at this point I just replace all 6 and be done with it.

Link to comment
Share on other sites

6 hours ago, JusB said:

Can anyone here, or should I say will anyone here give me some advice?
I suspect that this is a bad ECU. Likely a coil shorted and fried it. This means I need ECU and 6 coils.
That's a heap of cash to waste, with no guarantee that it solves the issue.
So, I was wondering...since I don't have access to sophisticated test equipment, can I unplug all 6 coils, clear the codes, and see what codes pop
then? If there is 12 volts at this point I just replace all 6 and be done with it.

The coils are fine, replace them if you want but that would be a waste of money. To be honest, There is another Lexus forum on the internet that seems more active then this one, clublexus, as I’m a new member myself. 

3 hours ago, JusB said:

Is there such a thing as an Ignition relay?

Yea, yea there is - if your specific vehicle has one or not? I don’t know. I used to change those on 90’s fords and gms all the time. 

Link to comment
Share on other sites

Would someone be so kind as to tell me where to find a diagram of the relay panel with labels as to what each relay is for?
This is for a 2007 Lexus RX350.
I have searched for over an hour and have had no luck.

Throw in a method for testing relays with an ohm meter and I'll dance at you'r wedding.
This box is under the hood, in fact it's under the reservoir for brake fluid.
Is there a conspiracy afoot? This should take maybe 2 clicks to locate. I apologize if I have offended anyone here
I began this thread by stating that I have NO formal or otherwise, training or experience with Forums.

Thanks again and be Blessed.

Link to comment
Share on other sites

Sorry I forgot to mention that there is no cover on this relay box, nor a sticker with labels.

I have spent hours searching for this info, to no avail.

 

Link to comment
Share on other sites

You lack the equipment and the experience to effectively diagnose and trouble shoot this problem. It does not appear that you even have the service manual and diagnostic trees for this car, and that is a very basic item to have any chance or finding the problem. You are all over the map in what you have already looked at, and the information you have provided here is not broken down into the sequential steps and results of each test. There is a very defined and logical process that needs to be followed. Without that, even those of us that are really good at diagnosis and fixing can't help you remotely.

You can spend a whole pile of money firing the parts cannon, or you can take the car to a good independent, here my Dealer is actually great, trustworthy and fairly priced but that isn't true everywhere, that specialises in Lexus and Toyota. Once the issues are properly diagnosed, you can decide how to proceed.

 

Best of luck and let us know how this comes out.

Link to comment
Share on other sites

if you are not interested enough to give me some guidance, why would you want to know how it comes out? I may be all over the map. Maybe you live in a different world than I do, but some people have very limited incomes, and likewise very limited resources. I came here apologizing for my lack of etiquette, because I know that I'm out of my league. THAT is why I am asking for help. I'm in over my head and freely admit that. What I do have is the drive and desire to help a friend. This isn't my car but my neighbors. They need this car to run, and I have spent countless hours trying to get them there. Everything about this Lexus is a royal pain in the rump, Have you ever replaced a crank sensor on one of these? I had to remove the windshield wipers, motor and cover just to change a cam sensor.

Sorry for venting, but if you wont help, please don't get me sidetracked with snide comments.

Link to comment
Share on other sites


Spud, there was not one snide comment in anything I said. I did not even mention that 3 hours after your first post you were back going where is everyone, why aren't you all falling all over yourselves to help poor little inexperienced me. It is my right to get free help from people I have never interacted with nor have I ever posted anything of any use on the forum. Your subsequent posts were not any better, you can ask for latitude for lack of etiquette but being rude and ungrateful is a whole other matter. Do you have the remotest idea of how many one post wonders a guy sees on car forums, asking for help with next to zero information of use to help with. Dragging pertinent info out of an OP gets old in a hurry.

I clearly told you, get a service manual, and Techstream or take it to a shop. You have already had him spend more on parts than the diagnosis would have likely cost to start with and I have no idea what else is now messed up because of your random fiddling. Did you even use OEM replacement sensors?.

Your friend needs this to run, you aren't getting them there and no one is going to be able to help you with the information you are providing in your posts.

Link to comment
Share on other sites

Wow, overinflated ego. I didn't mean to step on your toes. I think you live in a different world. 

I've not been rude, I have said please and thank you. I sat here dor over 12 hours hoping for some sort of direction, and naturally I wandered to other issues. Nobody told me how to proceed.

Car cranks but no start. No power to fuel pump or ignition coils. The scanner said crank sensor,and 6 bad coils, so I replaced it.Now I get camshaft sensor code. Still no power to coils or fuel pump. 

People who live on fixed incomes cant afford the Dealershhip on a 17  year old car. 

And for the record smartypants, you talk about the one posters, sure I can imagine your frustration. 

What you fail to take into consideration is the view from this side. 

Those same idiots that grieve your sense of self will gladly dump a crapload of irrelevant information out 

here and I have to wade through, sift and weigh this just to get to a kernel of fact. 

If you haven't the desire to help, leave me be.

Thanks for the diatribe, your highness.

Link to comment
Share on other sites

I would like to apologize if I have offended anyone. I know that I'm not very articulate, but I do try.

Just to give you an update, I finally found the map of the relay box, ( my covers are missing).C/OPEN relay was bad, and after replacing it I get only 1 code for Coil C. Still no power to coils or fuel pump.

I may have found the location of IG1 relay. Boy its hard to find some of this info. It's in a very difficult location, but thats my goal for today...

Hopefully that will be where the problem lies.

 

Thanks again and be safe

 

  • Like 1
Link to comment
Share on other sites

I searched " 2007 lexus rx350 electrical map " and chose Images, Way too many schematics to look at...Give it a go.

Link to comment
Share on other sites

hey are you a mechanic? or should I ask if you can read a schematic?

I can't. But...I have found the thread that will unravel my issues. My IG2 relay only gets power on the wire that tells the switch to close...it closes but it has no +12V to send to the coils. I need to know whats supposed to supply IT's power....

  • Like 1
Link to comment
Share on other sites

I am a mechanic when I need to be one, Not a profession. Just follow the lines in a schematic, It is strait forward and quite legible.  

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.



×
×
  • Create New...

Forums


News


Membership


  • Unread Content
  • Members Gallery