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Discussion Starter #1 (Edited)
Having a weird problem with my 02 5-speed, instead of hitting vvti like it used to, now around 4k rpm it feels like the power stops, almost like it hit a wall. It feels fine, nice and torquey, up until around 4k rpm, then it stops creating power and feels like the timing is retarding or something. It has check engine light, throwing two codes p0440 and p0446. I researched these codes but I'm not sure if they are related to my vvti not working. If anyone could help that would be awesome! spark plugs were changed about 20k miles ago, problem occurred about 10k miles ago.
Please help!
 

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Usually when it's VVTi related you will throw a P1349 and the oil control valve, responsible for variable timing, gets clogged up. It's possible your OCV isn't shifting right on the metal screen is partially clogged. Other than that, I would check your vacuum piping under the Y intake pipe and below it. There's a vacuum VSV and canister that have lines with no clamps and could physically fall off. The way you test the OCV is you warm the car up to operating temperature. Apply battery power to the two terminals of the OCV when the car is in park running. The car should immediately die or bog down and shudder. These links may help if you believe it to be VVTi related. Sometimes the mesh filter just needs cleaned.
http://my.is/forums/f115/vvti-ocv-install-430720/
http://my.is/forums/f115/help-misfire-codes-433820/index3.html

As far as P0440 and P0446, they are only EVAP emission codes and do not effect performance. It could be as simple as a bad gas tank lid or check by the firewall on the driver side. Verify the lines there are OK, especially the one that has a green service cap. Check where the stock air box sits. There a charcoal canister closed VSV, make sure it's hooked up and there are two lines on that valve(normally this valve mounts to the side of the stock air box).

This is a rundown of all the causes of these two codes.
http://my.is/forums/6459108-post17.html
http://my.is/forums/6459174-post18.html


Good luck.
 

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Yeah, stated above VVTi and VTEC are completely different.

I noticed using lower octane will also cause a loss of power
 

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Discussion Starter #6
OK VVTI doesnt "hit" but there is a noticeably increase in power that starts around 4k, my car does not get that, instead it feels like the car stops making power. The motor feels weak only above 4k, i will try n find the exact spot on the rpm band. So maybe its not a VVTI issue, but there is definitely something wrong here. Im glad the codes arent related and I will take it one issue at a time, starting with the CEL.

Im thinking its a timing or spark issue? I never had the problem until after changing the spark plugs, but the issue didn't start with the spark plug change so I'm not sure thats even feasible as the problem. Its not a clutch problem i know the difference there, its just really weak up in the higher rpms and I'm scared to take it past 4.5k because it feels like its working to hard for nothing.

Thanks for the help this far
 

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Discussion Starter #7
Ok so i peeked under and most looks good, except this one nipple on the exhaust manifold side that has no hose on it at all, and I think that might have something to do with the codes?? I dont know where the hose would connect to if it is supposed to be there, take a look...


 

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It's probably a dumb question, do you have enough oil? When was the last oil change?
 

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Does the VVTi 2JZ-GE have ACIS? I know my 7MGE and 2JZ-GE (non VVTI) had a butterfly valve in the intake manifold (which is why ours is split) that opened up around 4k RPM. It turned the intake manifold from dual 3 banks to a single 6.

The thing is if it's working, you won't feel the "hit" if it's not working as it should, it'll "hit" at 4k.

http://en.wikipedia.org/wiki/Acoustic_Control_Induction_System
 

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Yes, our 2JZGE-VVTi does have ACIS(acoustic control induction system). There's a ACIS VSV, vacuum tank and actuator down below the Y intake pipe. You don't feel the "hit", at least I don't.
 

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Have you checked your timing? Could be as simple as that. You check your spark plugs and coils to ensure they are plugged in the correct sequence? You said you never had the problem before you changed your spark plugs...did you use the correct type of plug? Since that was the start of your troubles, I'd remove everything and reinstall them. Its possible you might have missed one or maybe one of the plugs isn't threaded in all the way thus not producing a complete explosion or what not.
 

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I believe he is onto something here because I have a similar issue, although my setup is much more complicated. I too have a 2002 Manual that I switched from a AEM F/IC last year to Megasquirt this year. Long story short last year on the FI/C at the track running 10lbs I never had to shift out of 3rd gear my best run was 14.0 flat with a trap of 108. mph this year 10lbs have to shift to 4th gear and my fastest pass is 14.9 sec at 99. mph. It's like 1,2,3rd are all very torque'y and doing what they should, then shifting at 5800-6000 rpms. So at first i blamed the tune and Megasquirt but we are pretty sure it's not that yet (early adapter for Token). I compared my timeslips of multiple passes last year to this year and 1/8mi, 60', RT, is all the same but the car is def not what it should be in higher RPMS, Gears, and Speeds - it's a bit sluggish.



1. Changed Spark Plugs to IR gapped at .31
2. New NGK plug wires, and new COB
3. My intake track and boost leaks - there are none
4. I have an after market spec ii+ clutch, pp, and forza flywheel
5. I checked my OCV however I have no "catch screen on mine its just opened so no clogs"
6. All parts etc mechanical look to be in working order
7. I don't use a MAF
8. All fluids, filters, checks are in line

Next step for me is to move to the Gates Racing Timing Belt, Timing Belt Tensioner, Waterpump job - I don't see any missing teeth or slack but it does have 100k on the orginal so it's quite possible its worked loose"

So once that big job is done plan on making some more test n tune passes. Any other ideas would be greatly appreciated.

Any insight on Rev Limiter ideas.

I am working with Shawn (BlackSportD, the guys who created TunerStudio, and a few other gear heads - we still think it's mechanical but not ruling out a setting in TunerStudio either - however dwell, and rpms, etc are maxed to like 9k

Anyone else have issues on the manual giving a breakup sound or a big F-U around anything about 6k rpms like backfiring forcing you to shift prematurely>

One good thing did come of test and tune last night was my racing buddy pulled this off. I on the other had was so pissed trying to chase down the gremlins on my daily driver i refused to even been recorded lol

Adam's First Gen RX7 hauling fastest pass of the night 9.66 @144.6 after this run. - YouTube
 

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The oil control valve is the main component here for VVT operation. As it says in the manual..
The variable timing uses a few different signals to work. It's the control signal, applied to the oil control valve, which regulates oil pressure supplied to the VVT controller. Camshaft timing is performed based on engine operating conditions such as the IAT, TPS and engine coolant temperature sensor. The ECU controls the OCV based on these signals. The VVT controller regulates the intake camshaft angle using oil through the OCV to optimize performance with the car.
So if your filter isn't positioned on the banjo bolt right then you might have issues. The easiest thing to check is if the car dies or not when the OCV gets battery power on a hot idle. Making sure the amber bulb on the MAF(IAT) is clean is also good as well as making sure the coolant system is operating correctly.
 

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To clarify specifics I did not check the Camshaft Timing Oil Control Valve via battery method as of yet. I did clean it well and replace it, I may have to drop the 90 bucks if the test does not come back well. Correct me if I am wrong but the "Oil Control Valve Filter" sits in 22" mm Union Bolt where the Oil Pipe links up to. I do not have a filter in that bolt just the normal inlet/outlet holes in the bolt itself. I have all of the gaskets in tact.

I don't think that is my issue, basically car is hauling balls in boost just hitting rev limits on the rpms so at exactly 6100 rpm I have to shift or it goes pig rich and breaks up - some nice popp'n from the exhaust.

So it's on Jacks in the garage, have a small oil leak I am tracing down on the drivers side. Replace timing belt with Gates, WaterPump, etc. Kinda comb through the ride.

I am going to drop 90 bucks on a replacement OCV valve if this one doesnt test out tomorrow.

- to be continued.........
 
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