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By the way... What should be the normal read g/s from the MAF sensor
AS a "rule of thumb" the MAF reading in grams/second should be equal roughly to the liter displacement of the engine so 5.7...engine at normal operating temp I usually see around 6.5 grams/second.
AS a "rule of thumb" the MAF reading in grams/second should be equal roughly to the liter displacement of the engine so 5.7...engine at normal operating temp I usually see around 6.5 grams/second.
8.3 seems a little high and we call that an "over reporting" MAF (it is over reporting airflow)...this usually is a dirty MAF...with a dirty MAF you will see negative fuel trims at idle that go positive under load...try disconnecting that MAF. As you can see in the video he is going into Global OBD2 (check engine light symbol) and yours is called just OBD2. If that scan tool will let you select "open loop" you can see if the car will stay running when you accelerate. Are your upstream O2 sensors reading above 450mV at idle ??...they should be oscillating nicely between 200-800mV.
8.3 seems a little high and we call that an "over reporting" MAF (it is over reporting airflow)...this usually is a dirty MAF...with a dirty MAF you will see negative fuel trims at idle that go positive under load...try disconnecting that MAF. As you can see in the video he is going into Global OBD2 (check engine light symbol) and yours is called just OBD2. If that scan tool will let you select "open loop" you can see if the car will stay running when you accelerate. Are your upstream O2 sensors reading above 450mV at idle ??...they should be oscillating nicely between 200-800mV.
I guess I'll go tomorrow morning and buy a throttle body cleaner and a MAF sensor cleaner and go from there,,, I`ll keep updating !
Thank you so much for all the help! I appreciate it a lot!
I guess I'll go tomorrow morning and buy a throttle body cleaner and a MAF sensor cleaner and go from there,,, I`ll keep updating !
Thank you so much for all the help! I appreciate it a lot!
First I’d look at those data PID numbers as well as disconnecting the MAF…you won’t blow the engine up so don’t worry…I’ve done this MANY MANY times !!…you may just be wasting time cleaning but that is up to you…cleaning those 2 are part of my yearly items I like to do…cleaning the grounds are every other year.
First I’d look at those data PID numbers as well as disconnecting the MAF…you won’t blow the engine up so don’t worry…I’ve done this MANY MANY times !!…you may just be wasting time cleaning but that is up to you…cleaning those 2 are part of my yearly items I like to do…cleaning the grounds are every other year.
I did try to disconnect the MAF and it stalled.
Thing is I remembered that yesterday the MAF reading when cold was over 16 so maybe a good clean will be one step of the elimination process. plus I gotta let the car cool down.
First I’d look at those data PID numbers as well as disconnecting the MAF…you won’t blow the engine up so don’t worry…I’ve done this MANY MANY times !!…you may just be wasting time cleaning but that is up to you…cleaning those 2 are part of my yearly items I like to do…cleaning the grounds are every other year.
I see what you are saying, if the MAF is disconnected and it still stalls then its not the MAF.
What is PID ?
Yes, if the car still stalls with the MAF disconnected it’s not the MAF…a PID (Parameter Identification) are each separate item in live data you are viewing…below are 14 data PIDS on my scan tool at idle…my long term fuel trims maxed out on bank 1 when I had a faulty O2 sensor…bank 1 O2 sensor stuck low at 100mV.
Yes, if the car still stalls with the MAF disconnected it’s not the MAF…a PID (Parameter Identification) are each separate item in live data you are viewing…below are 14 data PIDS on my scan tool at idle…my long term fuel trims maxed out on bank 1 when I had a faulty O2 sensor…bank 1 O2 sensor stuck low at 100mV.
Idle before stall:
Idle after stall:
Idle after turning off the car with the switch after stall:
Idle after turning off the car with the switch after stall:
after tests, turned off:
Looking at the O2 sensors in all of your screen captures tells me nothing unfortunately...the Sensor 1 O2's oscillate normally between 200-800mV and that screenshot only captures that point in time...you need to GRAPH the O2 sensors and post that.
Looking at the O2 sensors in all of your screen captures tells me nothing unfortunately...the Sensor 1 O2's oscillate normally between 200-800mV and that screenshot only captures that point in time...you need to GRAPH the O2 sensors and post that.
Looks like your Bank 1 Sensor 1 is stuck RICH if that is what you are seeing at idle at normal operating temperature...if the upstream sensor is rich (above 450mV) then the downstream sensor should also be rich…this might be an actual rich condition...try disconnecting either the brake booster hose a bit or the PCV line going to the intake manifold...we are creating a lean condition so see if that B1S1 goes way lean while graphing the upstream O2...if the O2 stays rich it may be a faulty O2 sensor...this is opposite of what I had...my exhaust stunk because the PCM was scheduling too much fuel to the injectors...your PCM is removing fuel so the car will fall flat on its face...your stall possibly.
Looks like your Bank 1 Sensor 1 is stuck RICH if that is what you are seeing at idle at normal operating temperature...if the upstream sensor is rich (above 450mV) then the downstream sensor should also be rich...your downstream on Bank 1 is looking rich so this might be an actual rich condition...try disconnecting either the brake booster hose a bit or the PCV line going to the intake manifold...we are creating a lean condition so see if that B1S1 goes way lean while graphing the upstream O2...if the O2 stays rich it may be a faulty O2 sensor...this is opposite of what I had...my exhaust stunk because the PCM was scheduling too much fuel to the injectors...your PCM is removing fuel so the car will fall flat on its face...your stall possibly.
in this photo you can see when I disconnected the brake booster hose:
and here it`s idling after the hose is back on:
1. The engine reved a bit for a second or two when I pulled the hose.
2. Maybe the temp went up and it started responding ok.
in this photo you can see when I disconnected the brake booster hose:
and here it`s idling after the hose is back on:
1. The engine reved a bit for a second or two when I pulled the hose.
2. Maybe the temp went up and it started responding ok.
The O2 sensor responded to a lean condition so it looks like the sensor is OK…now it looks like the O2 is working OK…what happens if you let it idle for a while ??…does it go rich again ???
Check the short term fuel trims for each bank.
I had a drivability issue for years that turned out to be bad injector orings leaking air. Found by watching the O2 graph while spraying propane gas from a torch (not lit) on the injector area.
The O2 sensor responded to a lean condition so it looks like the sensor is OK…now it looks like the O2 is working OK…what happens if you let it idle for a while ??…does it go rich again ???
Hook everything back up…looked like the O2 was switching normally but in the previous post you showed it being “stuck” rich…so is it working OK with the hose reconnected like it shows in the last post ??
Hook everything back up…looked like the O2 was switching normally but in the previous post you showed it being “stuck” rich…so is it working OK with the hose reconnected like it shows in the last post ??
it looks like it is working ok after the hose is connected (the second picture) but the fact that I unplugged the hose "woke" it up
You will have to check if it stalls now when it’s cold…when the car starts and is open loop until the O2’s heat up the fuel trims will not be doing anything until the O2’s are heated up…see if the car stalls when in open or closed loop…if it stalls in closed loop see if that scan tool of yours has a special function to allow you to select open loop…these are all GUESSES here…if I was looking at your car I’d have my scope hooked up to a few things and see what drops out when it stalls.
