Pennies350

Hi everyone

Looking for some help. My wife's is350 started bogging and then now won't start. It started when she put gas in her car (91 octane) and about an hour later of highway driving, it started to miss and you can could hear the valves. Check engine light came on right when this started. We were about 5 minutes from home so we were able to drive it home. After I let it sit for 5 min, she won't start now.

I checked the CEL and it was P0340, camshaft position failure. I have a cheap scanner so it also brought up random things (not codes) such as catalytic, fuel, O2.

Here's where I need help, I'm Not sure where the camshaft position sensor is on the motor so if anyone could help tell me where or provide a diagram. I also tried to siphone the gas out but I believe it's got a check valve preventing me from doing that. I also do not believe it has a drain plug as well so advice on how to get the gas out will be great. I can do most of the work myself as well.

Also, any thoughts of what else the problem could will be great.

Thanks

Cheng

meteoro

I ran into a similar situation with mine at around 90K miles. It turned out to be the O2 sensors, sparks plugs. I had never replaced them, and they met their end. I could hear the car knocking, and sputtering to the point it would almost stall. I would have to put the car in neutral and had to keep the revs up, if not it would stall.
Seems running the car with old spark plugs eventually damaged the O2 sensors, and the one in front of the cat (called something else). The sensors are not cheap!

Pennies350

Thanks for the answer. I've never replaced the spark plugs or coils since I bought them new.

Would the damage O2 cause the ecu to not start the car?

nielsio

It can, if the sensors are not getting a read on the oxygen, the ecu does not know what to do with it. Best to replace when you're at that milage.

Gville350

iTrader: (10)

OP, how many miles on the 350?

mong

iTrader: (4)

Same code happened to me but it was caused by a bad battery. Dealer replaced my battery and the code went away.

Pennies350

I'm at 120k.

Also, anyone know where the camshaft position sensor is?

Evitzee

This is something you aren't going to be able to diagnose and fix yourself. It could be a bad tank of gas which has messed up the dodgy plugs, or something else. Time for a trip to the dealer for a diagnosis.

Pennies350

Tried it again, started 2x and bogged really bad. Now it just clicks

jgr7

iTrader: (1)

Better have the battery checked as well as the alternator.

Pennies350

The battery negative is corroded and has been since around 50k. Ill pull that to get check as well Ill pull the alternator as well. I did pull one if the spark plugs out and it does look worn. Ill replace then as well seen that I haven't done so yet

Pennies350

Ill at least try. Again, looking for where the camshaft position sensor is on the engine. Does anyone have a diagram?

Pennies350

still looking for some help on where the camshaft position sensor is

Pennies350

Well If it looks like how my Evo camshaft sensor looks like then I found both of them. Im going to get a multimeter to check for voltage tmmr. In the mean time, any other advise would be great before I take it to the dealer

5gears-IS

iTrader: (5)

I will say it is NOT the cam shaft position sensor, that is just one of the things that may be represented by the code but that sensor hardly ever goes bad.

Based on your description I would:
1) Change the spark plugs with fresh Lexus OEM plugs
2) Check the battery voltage and replace it if bad.
3) You don't need to remove the alternator to check it, once the battery is replaced or fully charged and engine running remove the negative side of the battery terminal and if the engine shuts off your alternator is bad (old *** trick).
4) If the top 3 things check ok and you still have the problem then the 02 sensor may be the problem.

By the way I use 87 octane on my IS350 with no problems whatsoever! I am at 123k miles!