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When your car is misfiring/running horribly, the engine vacuum will be extremely low. That is why the brake pedal feels stiff. You don't have engine vacuum to assist in braking. I'm still going with a sticking oil control valve for the VVTi. If the intake cam stays in the advanced position it will run fine over about 2000 RPMs, but at idle it will sputter, misfire, and generally run like a bag full of buttholes. You can try cleaning the valve, but I've never had any luck with that as a permanent fix.
 

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I agree with you for the most part wkeryder. I can't feel it at high RPM's however in high gears when your RPM's go down i can feel it but not as bad as when stopped or rolling slowly. As for the OCV i am having it replaced as we speak alog with all my O2's, i will update as soon as possible. Thanks everyone for lending some thoughts, it cant elude all of us!
 

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Discussion Starter #43
Yeah it comes up to running temperature easily and I replaced the battery about three months ago. I will check on the OCV valve as well. LETHLEX if you wouldn't mind me asking what is replacing the OCV valve running you?
 

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Not sure yet.. I know my tech fairly well so I rarely ask cost. He sent me an email with the cost of O2's wich I'm paying his cost and OCV wich came to about 220$ for parts but his labour is not cheap. From the tutorial Jasonm4444 posted about the OCV it looks pretty easy to replace.
 

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It is pretty easy and straightforward. I have other instructions around somewhere if needed. My question is have you tested or inspected the oil control valve as i suggested? I go with Cline because he's a knowledgeable lex tech here, but it's always a good idea to test it and check it's operation. Test it on the car running and apply battery voltage, or pull it and inspect it as mentioned. I wouldn't replace the secondary post oxygen sensors. They may last alot longer and not critical. If the car has more mileage then replacing the primary oxygen sensors is justifiable. I hate to see folks spend money before doing some testing. Just my 2 cents.
 

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Discussion Starter #46
Okay so after looking at Jasonm4444's install of the OCV valve I noticed that the oil control wire that plugs in there is one of the connectors that I mentioned earlier in the post that the clip on them broke just from age the part that clips into place when reattaching it broke off. The plug itself is not loose but could that actually be affecting it, and if so how would I go about fixing that just buy a new connection and solder it into the old one?
 

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Discussion Starter #47
Hey Jason how would I test the valve, or upon inspection what should I be looking for and do you have the instructions if possible?
 

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The clip on the connector being broken will not have much affect on the valve as long as it is plugged in. You can test operation of the valve by applying power and ground to it while the engine is running. If it is working correctly the engine will run very rough/stall. What I suspect is going on is the valve is sticking in the open position. To test for that, disconnect the electrical connector and take it for a drive. This will prevent it from advancing the cam, and probably set a DTC. If your car does not start running rough on the test drive then replace the valve. It is simple to do, just remove the upper timing cover, and the single ten mm bolt then pull it out. Install the new one and bolt it in.
 

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Well here is the removal steps outlined some, not much to it.

http://my.is/forums/f115/vvti-ocv-install-430720/#post6447312

And to test it..you just apply a positive and negative wire from the battery very carefully, and pull the solenoid connector to give the solenoid battery power. The car should stutter or stall but will definitely change and that is good. here's one of my previous posts. I believe the OP had a P1349 as Cline100 mentioned so it definitely was bad. Using conventional oil can wear it down.
Jasonm4444 said:
Possible causes are...
-Oil control valve
-VVT controller assembly
-valve timing
-ECM

What you would verify first is that the timing is correct(ie. timing belt jumped a tooth). If timing is ok, the OCV is next and needs to be checked. There is a mesh filter in the OCV that can cause it to stick and mess the timing up. In order to test the OCV operation, you need to pull the two wire connector off and apply battery voltage to the two terminals on the valve. At idle, the car should run poorly and possibly stall out. Then remove power to verify the car returns back to normal. That would verify the valve itself isn't sticking. Here is the oil control valve, responsible for VVT.(pointing to it)



After those tests, clear the code and see if it comes back as the diagnosis goes a bit further and it could simply be a sluggish OCV, which is common, especially with folks who use conventional oil. Reset the code either by scanner or remove the negative battery terminal for 5 minutes. Then allow the car to warm up and drive it around for at least 10 minutes. Then report back your results and if it comes back.
Edit: Sorry Cline, i was writing this book and didn't see your post. Good post, i think you may be right in the OCV here.
 

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I was a little confused when my tech said he tested it and it stalled the car out (wich means its fine?) so I was bummed but then he said he then removed power and the car did NOT return to normal wich indicates the OCV is faulty?
 

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I was a little confused when my tech said he tested it and it stalled the car out (wich means its fine?) so I was bummed but then he said he then removed power and the car did NOT return to normal wich indicates the OCV is faulty?
Yea, it doesn't sound like the valve shifted back. It should've started up fine when power was removed. When the car is idling and power is applied, it should stutter or stall but recover when the valve is de-energized.
 

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Right, no recovery from what he says. Really appreciate all the help Jasonm4444 Crossin my fingers cause up here in Canada we don't have much of a warm period for lovin our customs.
 

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Discussion Starter #53
Well I swapped B1S1 and B2S2 today and the car is still doing it. Actually stalled completely this time. Im about to head to the toyota dealership and try to order a OCV.
 

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Update!! Got my car back today and the prognosis is positive! Had the OCV changed, he said he tested it multiple times and each time it stalled both turned on and turned off (it was clean too) Took it for a good test drive around the city and highway and it runs awesome! After changing all the plugs etc. my Power is much better too. Hope I'm not jinxin' shit! As for running rich I'm still a bit puzzled, changed all O2's and it's still running rich.
 

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Don't wanna get my hopes up just yet. Read too many posts where the problem comes to fuk you over the next day. Again I appreciate your help and Clines, hope it works for wkeryder too!
 

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Discussion Starter #58
Well guys I replaced the OCV valve today and the problem is gone. The car itself is running better than it has in years and no CEL so far. I can't tell you guys how much I appreciate your help, I would have never been able to figure this out on my own. Thank you guys so much again.
 

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Awesome! glad to hear it work out for you too! was it dirty or faulty? My engine light came back on but i had all my O2's replaced and my tech said when he replaced them one was actually disconnected....? so if your light comes on stop by and ill scan it he says. Going today to see but all and all she runs like a fukin champ! After the engine light came back on however the i still noticed a bit of misfire/sputter going on at low rpms when gearing down. maybe not enough back pressure?
 
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