Please help with understanding OBDII live scan results

This is all while idling. I figured I'd show it getting up to operating temp, however if you want to skip ahead, I put it into drive at 4:40, then I struggle to get it into neutral at 5:45, reverse at 6:20 & then back to park at 6:50. Oh, & try & not let the phone distract you too much.

 

What are you trying to figure out or having problems with?

 

Your idle seems a bit high to me, in both park/neutral and in gear.
That might be why it’s a bit hard to get into and out of gear.

 

Ha-ha! Sorry. I should have clarified. It was just the angle I was at what with trying to keep the camera on the phone while shifting.

The high/rough idle is the main one. & I'm not sure why it doesn't show on the phone when I turn it sideways, however the scan states I am stuck in a closed loop. My understanding is it's supposed to go to open when I first start the truck & when I coast.... It does not.

 

Closed loop is good. Open loop turns on when ther is errors and money light pops on.

 

Rough like a misfire?

 

No. well, maybe? Go to around 6:40 in the vid. That's with me holding the cam, elbows on the arm rest. Then I switch to park & you can see the dif. The rough idle is in gear & i can kinda hear it at times through the exhaust? I did the manifold crossover gaskets & thought that took care of it. I pass the smog test on the scanner.

 

I see the timing is off, but isn't that adjusted for by the ECU? There's nothing I can do to fix that, correct? I mean short of doing the belt.
One thing I have not done is valve clearance.

 

passed compression test. coils, plugs, wires, injectors, all done

 

Timing belt on these engines skip around every cycle and You would probably be having more serious issues if that was off. You were having this problem before all this was done?

 

Clean MAF sensor or Bad gas maybe? Any exhaust smoke?

 

I think loping is what it's called.

I was actually having a low idle. Then I went down into the intake manifold & cleaned the crud out of everything. When I was done, the idle was high. That was last summer. Been chasing it off & on ever since. It was suggested by TW members that I get a live scan tool to help pinpoint the prob.

 

Possibly a vacuum leak. How are the lines looking going to the intake? Any micro cracks in the rubber?

 

This is where I started cuz I was hearing hissing. I had already replaced all the hoses. So I doublechecked everything & re-swapped out a few of the new silicon ones for fuel line, like at the brake booster. Then I found out I needed to do the manifold crossover gaskets. Thought that would take care of the idle issue & the hissing. It did help some with the idle, just not enough. I do swear I still hear a hissing though. Somewhere drivers side toward the firewall.... I did an engine vacuum test going through the booster coupler & passed. Thought it might be the booster since it got skipped in the test, however that's ok as well.

 

Track down the hissing. Get a spray bottle with a drop or two of dish soap and start spraying lines. You're looking for a change in idle.
Replace any lines that fluctuate the idle when sprayed.

 

What's the point of the IACV then?

 

To allow air around the throttle plate when it's closed at idle. And control rpms when loads are added like AC and power steering. Once they went to electronic throttle bodies the throttle motor controls it all

I doubt you have an intake leak, the long term trim would be high positive, not negative.

All the data looks pretty good, but i agree the idle is a little high.

Since you mentioned the IACV have you checked it? Is it gummed up with carbon, can it close fully? Can you block it off with gasket paper or something. See if the idle comes down

Is the throttle cable routed correctly? Is it taught against the throttle plate or is there some slack? Unhook it or loosen it up

 

@Smokestacks stated, having a constant closed loop is best. Wouldn't this mean the IACV would be closed at all times?

 

No closed loop means the computer is looking at the oxygen sensors for more precise fuel control.

As apposed to open loop like when it's warming up or there's a problem so it goes into fuel enrich to protect the engine

Idle air control valve doesn't affect fuel mixture. Just idle speed

But he's right, closed loop means the computer is happy. Idle can be a touch high and the computer won't notice

 

My live scan states that I am stuck in a closed loop. I put this in a later post, so this is why it is part of the discussion. It is not open when warming up & I believe my high idle indicates there is a problem, yet I stay in a closed loop.... always....

I got to reading a post on Toyotanation & I guess I must be misunderstanding it. I pulled this from the post.... maybe it's a different type of IACV?

"Feedback (Closed Loop) Idle Air Control

The ECM has a preprogrammed target idle speed that is maintained by the IACV based on feedback from the NE signal. Feedback idle air control occurs any time the throttle is closed and the engine is at normal operating temperature. The target idle speed is programmed in an ECM look up table and varies depending on inputs from the A/C and NSW signals. Any time actual speed varies by greater than 20 RPM from target idle speed, the ECM will adjust the IAC valve position to bring idle speed back on target. The ECM utilizes a feedback idle air control strategy. That is, when the actual engine speed is lower than the target idling speed, the ECM signals the IACV to open. Conversely, when the actual idle speed is higher than the target idle speed, the ECM signal the IACV to close."