Werner05

If anyone can point out whether these numbers are typical (or something abnormal) would be greatly appreciated.

taken while on idle (2005 ES330)

sparkadv - ranges from 4 to 30 but seems to average out around 15.

MAF (g/s) - averages out around 3.

TP(%) - 15

O2B1S2 - around 0.78 V (constant, does not change unless the gas is pushed then it goes to 0 V, then climbs back up)
O2B2S2 - around 0.76 V (same as the above, does not seem to change unless gas pedal is pushed then it goes to near 0 V)
SHRTFTB2S2 - 99.2%


EQ_RATB1S1 - 0.992
O2B1S1 - 3.2 V (constant, no change)
EQ_RATB2S1 - 1.007
O2B2S1 - 3.3 V (constant, no change)


no codes

nsghtbrwry

What's the context? As in, is there something in particular you're trying to troubleshoot?

Werner05

The car sometimes hesitates and jerks on the highway and has delay issues in the acceleration from time to time. I'm wondering whether the oxygen sensors are working properly or if there is inadequate amount of air flow into the system. Shouldn't one of the sensors be changing from 0.1 V to 0.9 V? Whereas my readings seem to be constant at idle. The fuel trim data is reading well but the car changes from CL to OL drive from time to time, which may mean that it's disregarding input from the oxygen sensors occasionally.

Also, wondering what the sparkadv numbers are supposed to be.

nsghtbrwry

Well, spark advance will change with engine RPM; specifically, it'll go up as the ECU wants to ignite the air-fuel mixture earlier so the flame front coincides with the piston getting to TDC faster at higher RPMs.

The downstream O2 sensors are not wideband, so they basically go from 0V to 1V, which is lean to rich. When you press on the gas, it dips because the throttle opens and more air is passing through before the ECU reads that (via the MAF) and compensates with more fuel to bring it closer to stoich.

When does it go open-loop? At WOT, cars go open loop (the ECU relies on a lookup table entry). Some vehicles (BMW's larger engines) go open-loop on throttle closure at speed (under normal engine braking).

Are you sure it isn't the quirky behavior of the drive-by-wire Toyotas? I refuse to own a DBW Toyota myself, but maybe somebody else can help you figure that out

Werner05

I got the impression that one of the o2 sensors was supposed to be moving constantly between 0 and 1 V, whereas both of my o2 sensors seem to remain at 0.7-0.8 V until the gas pedal is pushed.

nsghtbrwry

On older cars with slower-responding/primitive closed-loop operation, yeah. But these have wideband sensors upstream and better algorithms. The ECU uses the upstream (wideband) sensors to decide how much fuel to inject at a given throttle (let's assume the amount of air at a given throttle position is unchanging, as verified by a properly-functioning MAF). So the exhaust coming out, assuming everything else is the same, is going to be the same mixture (i.e., have the same amount of oxygen) and the downstream (narrowband) sensors will read that until the throttle changes. The downstream sensors aren't used to make decisions per se, they're just to monitor cat operation.

Werner05

Much thanks. So how can I tell if the cat is going bad? This has been a concern of mine ever since I filled up at a particular gas station (and afterwards got the vsc and trac off lights).

nsghtbrwry

So, on MZ-powered cars (1MZ and 3MZ like yours), the engine is equipped with Toyota's ACIS variable-length intake system. It's to optimize engine output under different conditions...one such use is to modulate engine power for traction control. That's why whenever you get a fault/code that has to do with ANYTHING that could affect power (thus robbing the ECU of its ability to accurately predict engine output), the TRAC OFF and VSC lights go on, indicating that traction control/vehicle skid control have been disabled.

That, or there's a fault code set for the ABS system. You should read the code(s) and report back.

If a cat is going bad, it will almost always throw a P0420. Bad gas - as rare as it is nowadays - is unlikely to kill a cat. They just reduce in efficiency over time, might be due to diminished catalytic action, or due to being dirty.

If a cat is physically clogged, you can test it by seeing how the car performs at WOT normally, and again after removing an upstream O2 sensor (which will allow exhaust past a restriction). If the car wakes up with the O2 sensor removed, you have a clogged cat.

speedkar9

That's how the 4ES is supposed to be ... transmission and throttle lag. Sigh.

nsghtbrwry

That reminds me, there's a guy that reviewed a Chinese throttle controller recently that you might be interested in OP. Far cheaper than the name-brand ones and seems to do the same thing. That seems to be the main solution for the DBW "problems."

EDIT: Here: https://www.clublexus.com/forums/es-...l-lag-fix.html

Werner05

Ok, thanks to all who helped me out on this.