Code p0340 with misfires

[Hende]

Hello all, I am new to this forum but I have some experience with these types of things. I am sorry in advance to make my first post a question but this problem has been plagueing me for awhile now.

I have a check engine light code p0340 camshaft sensor, along with p0300 the multiple misfires detected. When I start the truck it immediately starts to idle high around 2000 then slowly drops to normal after like 5 min which is way too long. But sometimes it will then continue to drop below normal idle to like 100- 200 range and will basically stall out unless I stop and restart the car. It also only misfires when the high idle has stopped and I put the car in drive and start going. The most bizarre part is that this doesn’t happen everytime lol it’s like a crapshoot as too wether any of this will happen. Normally this happens on a cold start or the first start of the day but if I start it later on after the car has warmed up it seems to run and drive just fine.

Now I have tried new spark plugs, new distributor rotor, Cleaned the contacts on the iac valve and distributor cap. I also took it to the stealership and they said my camshaft position sensor was fine along with all the connections but said it was my distributor and wanted like $1000 just to put in a new distributor. I have heard of the o-ring trick but I don’t think that will work as most people who had the same code did not have misfires as well unless I missed a thread or two but I am willing to give that a try if need be. In my opinion it seems like a valve or something as once the car is warmed up it works fine. I would love to hear what you guys think before I start replacing uneccessary stuff any help would be much appreciated.

 

[Tools R Us]

The camshaft position sensor is in the distributor, IIRC is serviced as an assembly from Toyota. Could be the sensor, or a connection, wiring problem between there and the ECU.

 

[Hende]

Thnx for the reply, So you think I should go ahead and just replace the distributor? The dealership said my connections from the dristributor to ecu and the camshaft sensors were good but I mean they could be wrong. Would I use a multimeter to test this? I find this confusing though because if it was a connection wouldn’t it misfire and high idle everytime I start the car?

 

[Hende]

If anyone was following this or interesting which I doubt but anyways I have solved this issue. Finally got some time and garage space to work on the car it’s a little hard since I go to a 4 year university. After doing some research and testing I decided to try replacing the iac valve so I went to a car dismantler and got a new entire throttle body assemble for $90 took out the iac valve. And dismantled it along with my old one and then mixed and matched the good parts together to make a “new” Frankenstein iac valve. I made sure to clean everything and sprayed contact cleaner on the connections. I then plugged the iac valve and made sure everything was connected. First try starting it up it didn’t want to idle and seemed out of tune, let it sit tried again it idled but not great, idle was shaky and rough but giving it gas it was smooth. Let it sit again and started it for a third time and it started right up no high idle, no shaky idle like the previous start, car sounds 10x better now and runs a lot better that iac valve seems to be the fix if anyone else has this issue I highly recommend you try this as it’s not very hard the bottom screw is a pain but doable and if you go to an auto dismantler parts are cheap and generally come with a small warranty if it doesn’t work

 

[Kernal]

Thanks for the update.

 

[Hende]

Ya only took a few months but I’m happy the car is finally idling smooth and running better now to put in my new rcv axles

 

[tjones8]

I’m having the same issue currently. It’ll idle low sometimes at 200 and when giving it anything over like 20 percent throttle it’ll misfire very violently. Yours misfired driving at low RPM/speed right?

 

[Hende]

That is sort of similar but it sounds like you have something more serious going on. Mine would only misfire when i put it in drive, started driving when i would come to a stop it would idle low like what you are saying around 200 and misfire. Under throttle mine would never misfire.

I was also meaning to update this post as it is winter again and sadly my fix has not worked, although it did work for a little doing cold starts. I think there is something else going on besides the IAC valve, but when i put my "new" IAC valve it did idle way better than the old one so who knows i need to do a little more messing around with it.

 

[tjones8]

That is sort of similar but it sounds like you have something more serious going on. Mine would only misfire when i put it in drive, started driving when i would come to a stop it would idle low like what you are saying around 200 and misfire. Under throttle mine would never misfire.

I was also meaning to update this post as it is winter again and sadly my fix has not worked, although it did work for a little doing cold starts. I think there is something else going on besides the IAC valve, but when i put my "new" IAC valve it did idle way better than the old one so who knows i need to do a little more messing around with it.

I see. I don’t have a ton of time to dig into it unfortunately so I’ll have to get to it when I get to it. And finding OEM parts may be a hassle, really don’t want to put Duralast/Dorman stuff in

 

[Hende]

Ya I've been meaning to do the same with mine hopefully i will find some time soon. Ya i feel you there that duralast and dorman stuff is terrible. although i did put a duralast brake booster in hopefully wont see any problems there. I got my parts at a Toyota dismantler yard, i see you are from sac it was actually in sac at the rancho cordova toyota recycler yard out there. I would suggest going there before buying expensive new parts its pretty cheap there, they have every part you could need and comes with warranties if the parts don't work.