Lexmex

I know what you mean. I had a misfire (dead coil, not malfunctioning) back in Dec. 2005 and that was a sputtering one, shaking all over the place.

p1fcl01

OK, used my friend's OBD2 reader and these are the results. I really don't like it, but what can I do. Please help with these code and please let me know what I can do to fix this. Thanks

Also Meetya, where are the four A/F Heater sensors you are refering, I can check that.

Codes in order:

1. P0300 - Random/Multiple Cylinder Misfire Detected
2. P0302 - Cylinder 2 Misfire Detected
3. P0304 - Cylinder 4 Misfire Detected
4. P0306 - Cylinder 6 Misfire Detected
5. P0171 - System Too Lean (Bank 1)
6. P1153 - Fuel Control Shifted Lean

The car's jerking is more than just one jerk, it's like someone using a hammer banging the back 10 - 15 times. I can now smell the fume even inside the car with the A/C on, horrible smell. Please see what you guys can do to help me fix this.

Thanks
Frankie

Meetya

Here is some corrections:
1. P0300 - Random/Multiple Cylinder Misfire Detected
2. P0302 - Cylinder 2 Misfire Detected (Bank 2)
3. P0304 - Cylinder 4 Misfire Detected (Bank 2)
4. P0306 - Cylinder 6 Misfire Detected (Bank 2)
5. P0171 - System Too Lean (The whole system, not just Bank 1)
6. P1153 - A/F Sensor Circuit Response Malfunction (Bank 2, before catalyst)
I am almost certain that malfunctioning A/F sensor caused the computer to change the air-fuel mix, which caused misfires in the whole bank.
You are lucky, it is Bank 2 (Front of the engine).
Anyway, here is what to do:
1. Check resistance of that Bank2 A/F sensor heater.
2. Remove plastic Engine Cover.
3. Inspect all wires, and vacuum hoses.
4. Check Coils and Inspect Spark Plugs on that bank. Make sure you get spark on all cylinders.
5. ...Take it to head shop and ask them to make a compression test.

What is your mileage? Have spark plugs ever been replaced?

p1fcl01

[/QUOTE]I am almost certain that malfunctioning A/F sensor caused the computer to change the air-fuel mix, which caused misfires in the whole bank.
You are lucky, it is Bank 2 (Front of the engine).
Anyway, here is what to do:
1. Check resistance of that Bank2 A/F sensor heater.
2. Remove plastic Engine Cover.
3. Inspect all wires, and vacuum hoses.
4. Check Coils and Inspect Spark Plugs on that bank. Make sure you get spark on all cylinders.
5. ...Take it to head shop and ask them to make a compression test.

What is your mileage? Have spark plugs ever been replaced?[/QUOTE]

1. Will check Bank2 A/F sensor. Is this the one near the top of the engine bay mounted to the exhaust manifold?
3. What am I checking on wires and vacuum hoses, if they are lose and connections?
4. How do I check this, the coils and sparks on all cylinders? Do I actually take the spark plugs out and see if spark are visible?
5. Do I really have to do this and what's the cost of this test?

The car has 115,000 and plug were replaced around 70,000.

Thanks

Frankie

p1fcl01

Bump... Meetya, please!!!!

Meetya

Just do number one (check the sensor) for now. Do next steps only in case previous ones don't fix the problem.

For number 3:
Make sure there there are no loose wires.
Here is a picture of a cracked vacuum hose:


For number 4:
Be careful not to get a shock. It is really painful to your hands. Also, multiple high-power 30,000 volts discharges to your chest are enough to make you unconscious.


For number 5:
Do this only if steps 1-4 did not fix the problem. The cost depends on a machine shop (use Yellow Pages to find Machine Shops in your area).

p1fcl01

Thanks Meetya, I try that once I get home today.

A co-worker told me he had the same issue before due to a dirty bank 1 sensor. He threw in some techron and the car ran fire in sequence again, working fine. He did say not to use regular gas since that can dirty the sensors. I've been using regular for a bid, I'll stop now on. Will report back the status, Thanks

edbro

How does regular dirty the sensors? I thought the only difference was octane level.

Meetya

Usually Premium is dirtier than Regular, because most of gas stations store Premium longer. Less popular = dirtier. Midgrade is probably the worst. Gas may be stored in good condition about one month.

When gasoline is left for a certain period of time, gums and varnishes may build up and precipitate in the gasoline, causing "stale fuel." This will cause gums to build up in the cylinders and also the fuel lines.

p1fcl01

The resistence test show 0, which meetya said I will need to replace my a/f sensor, right? Well, that's $165 shipped from ebay, factory OEM from a Lexus dealer. I can't find anywhere cheaper for factory OEM.

Thanks meetya....


I'll report back result after the replacement.

Meetya

The heater on that sensor is burned out. I think you found the culprit.
I just sent you a PM, please reply.
BTW: I hope you used digital ohmmeter, because it is hard to distinguish 0 and ~1 Ohm on the one with arrow.

p1fcl01

Already ordered, I'll see if I can cancel.


I have never used these things before, got it from a friend and it's not digital. It is with the arrow meter and it states X1k, whatever that means. I better re-check this. Now the right side of this meter is 0, then slots then 1 and so on. with this being a X1K and resistece of 0.8 - 1.4Ohm. The arrow should be between a little pass 0 and 1.5 on the meter, right?

Now I'm wondering maybe my measurement was not correct and my a/f sensor is really good.

Sory, but lost again........

Meetya

x1K means that the readings will be multiplied 1000 times. So if the scale has 0-10, it will show measurements from 0 to 10000 Ohms. Where it would be really hard to distinguish 0 from 1 Ohms. You can borrow a digital multimeter from Walmart,Radioshack,Autozone,Home Depot,Fry's... and then return it back.

p1fcl01

Meetya,

Would this one do? It's digital but I think its at least 200ohm minimum.

Meetya

Yes, this one's good.
If you set it in 200 Ohm, this means it will measure 0-200 Ohms with about 0.01 Ohm precision.