2UZ differences

[Awz]

I know the subject has been brought up before but I was hoping for some more information.
Are there any differences between the engines (Tundra, Sequoia, LC, Lexus, 4Runner) other than one was made in Japan and the other in the US?
I'm still fighting a secondary air code after a year and a half. The bypass didn't work before anyone says it. Neither did fixing the exhaust leak or replacing the pump and valves. The next step is swapping my O2's side to side to see if it switches sides on me, seriously I'm grasping at anything now.
Looking through both a Chiltons and a Haynes manual it shows a two piece cast intake manifold, however my 4runner has a one piece composite manifold. I'm wondering if it's possible that someone preformed an engine swap at some point and some minor difference between the two is causing my grief. Or maybe this is simply one of the differences between a VVT-I and non VVT-I?

 

[4by4runr]

I believe all the Vvti v8 have a black plastic intake mani. Not sure exactly what it's made of since mine is cast aluminum non vvti.

 

[Awz]

Bump

Can someone with a VVTi engine look under their hood and tell me if their intake is metal or plastic?
This would help a lot.
Thanks

 

[Billynath1988]

my 05 vvti is plastic composite intake manifold

 

[Awz]

Thank you. Guess I'll keep looking. Or maybe it's just time to trade it in.

 

[BOFFROAD]

my 05 vvti is plastic composite intake manifold

Same here, 2005 VVT-i Plastic

 

[Billynath1988]

Thank you. Guess I'll keep looking. Or maybe it's just time to trade it in.

The [MENTION=8828]slyfox75[/MENTION] kit didnt work? is it in limp mode or just throwing codes?

 

[Awz]

I used the hewitt bypass kit. Keeps throwing the valve stuck open code even with the blockoff plates in place. And yes it's limp mode, otherwise I wouldn't care. It doesn't throw the codes when it should. Summer has been consistently in the 90's. Couldn't get anywhere without clearing the codes repeatedly.
Last week or two has been cold. Already dropped into the low 40's. Code doesn't come on after a cold start. Only after the engine has warmed up and I've run a couple of errands.
Toyota tells me I'm wrong and that's not what's happening but can't tell me what IS happening. I personally think it's the ECU, but the dealerships (I've taken it to two) won't even entertain the idea until they pull off the intake to confirm that the pump and valve were replaced correctly.

 

[Billynath1988]

I used the hewitt bypass kit. Keeps throwing the valve stuck open code even with the blockoff plates in place. And yes it's limp mode, otherwise I wouldn't care. It doesn't throw the codes when it should. Summer has been consistently in the 90's. Couldn't get anywhere without clearing the codes repeatedly.
Last week or two has been cold. Already dropped into the low 40's. Code doesn't come on after a cold start. Only after the engine has warmed up and I've run a couple of errands.
Toyota tells me I'm wrong and that's not what's happening but can't tell me what IS happening. I personally think it's the ECU, but the dealerships (I've taken it to two) won't even entertain the idea until they pull off the intake to confirm that the pump and valve were replaced correctly.

not sure what the hewitt kit consists of or if its any different then the one I have. Maybe go back and check the wiring of the kit? in its simplest form it should tricking the computer into believing the cats are at operating temperature and does not require pumped oxygen to heat up. so the fact that its throwing the code means the kit isn't functioning at all. ambient temperature really shouldn't be or I don't believe has much bearing on whether or not the AIP turns on. its more the temperature of the cats themselves around driving cycles. It does sound like the ecu is almost doing it back wards which is why it may be in your wiring or something with the MAF. [MENTION=66389]BlackWorksInc[/MENTION] ?

 

[slyfox75]

The system DOES use ambient air temp to determine AIP function or not.
The bypass I do tricks the ECU into thinking it is very cold outside at every startup for a few seconds before reverting back to actual ambient temp.
Sounds to me like you have a faulty bypass.....which is bad esp since you have the plates installed (pump trying to come on and plates blocking flow).

The more i think about it......I def think you have bad or mis-wired bypass. The system......once warm......should NOT put it it limp mode since it also looks at warm coolant temp. So once you have errands run.....it shouldn't come on regardless of a bypass or not. The fact your IS coming on makes me think the plates are making your limp mode worse in your case.(since bypass appears to not be working).

 

[Awz]

slyfox, I've removed the bypass, since it wasn't working anyway I took it out. The behavior never changed. When I first installed it or when I removed it. It didn't change after I had the pump and valve replaced, it didn't change when I fixed the exhaust leak. I even sprung for the Thorley's. It's always acted the same. The only thing is it's getting more frequent as time goes by. Tomorrow after work I'm going to swap O2 sensors from side to side to see if it changes sides. When the exhaust leak triggers this code it's the 02 sensors that do it. If that doesn't work I'm going to pull off the intake and double check the shops work. I don't want to do that, because I trust this shop. They've went back in and double checked it themselves after the repaid didn't take but I'm about out of options.