[cj1]

Disconnect the VVTi solenoid.,
Does it run ok at idle?

[cj1]

OP- if Malibu is flex fuel check that fuel sensor is accurately reflecting type of fuel.

[cj1]

Begin with the electrical schematic for start circuit.
BBBind.com has schematics.
Wire a test light from test point to drivers side.
When doesn’t crank and light doesn’t light you’ve narrowed down problem.
Eventually you will find intermittent in wiring or ign switch/ P/N switch/ start relay or starter.

If no crank is constant then of course you can test start circuit more easily with test light in hand.
P/N switch in automatic transmissions- try starting in neutral to test switch.
Start relay – swap with like relay.

[cj1]

If the parts were changed to fix the P0171 and it didn’t fix it then your mechanic owes you a refund.
Best bet for a fix asap, look for a shop that prides itself in fixing it right the first time.

[cj1]

The second o2 sensor( behind the cat converter) doesn’t control the fuel trim thus the 99.2% reading is false.
It should however have a normal voltage reading for after cat sensor.

The P0133 may well be the pre cat sensor is responding slow due to age.
Fix exhaust manifold leak first and retest.

[cj1]

bbbind.com has schematic so you can identify circuit/pins verify heater circuit from sensor ref circuit.
Regarding 4.4v when measuring across heater pins, measure again from battery side of connector to car body ground.
If voltage is normal then suspect high resistance in ground side of heater going to low control pin at PCM.
If v still 4.4v then suspect high resistance in positive side circuit.

[cj1]

Really don’t know the torque app capabilities. Post the engine parameters and with engine running and no error codes pending or set.

[cj1]

Make a note of the freeze frame engine parameters and then clear the codes.
When a error code sets the ECM stores a freeze frame( data such as fuel trims/RPM/ECTt This shows what engine was doing at the time the error code set.

The freeze frames you posted were then just snap shots of the engine parameters and not error code freeze frame?
Your scan tool may not have error code freeze frame info.
Does it have misfire cylinder monitor capabilities?

[cj1]

Can you post the same data at similar ECT when no error codes are recorded?

[cj1]

If check engine light is only on steady when car running then misfires not likely damaging to converter.

Seems Honda has been trying numerous fixes for this problem without much success.
Since misfires are so long in between and none damaging probably not worth it to pursue a fix unless you want to do some detective work yourself.
Can you post freeze frame data for the error codes?
Any engine parameters( fuel trimsECT|MAFMAPAFO2) that are suspect?

[cj1]

Does the check engine light ever flash during the misfire?
Just wondering if engine/cat converter being damaged.

[cj1]

Do you have a scanner to read live data? If so post both St and LT fuel trims at idle and at higher RPM 3000( hold for 1/2 min or so to give LT time to adjust)

[cj1]

Fuel pressure at idle should be around 40 psi. If you remove the vacuum hose from the FPR, pressure should increase maybe up to 50 psi.
This checks if the FPR is indeed working.

[cj1]

FPR can leak fuel thru vacuum hose to intake causing over fueling.
Was FPR tested/changed along with new pump?

[cj1]

Would think normal amp output at idle at least 10 amps.
Maybe there is a point at which output is low due to the ELD regulation.

Try another measurement with electrical loads headlights/HVAC etc on.

[Author]

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