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Thanks Pedro, the OBD2 dongle is already on it's way! :)Quote:
Originally Posted by Pedro_The_Swift
Crank Sensors aren't much fun to install either!
The performance has been deteriorating. It goes through some ok days, but usually it's not great. I just want to get all this sorted out, my patience is wearing pretty thin...
Those plug leads look like they sould be the correct type. Try some different plugs first, standard type not iridium or anything fancy just to see how it goes.Quote:
Originally Posted by s7000
OK, so the dongle arrived, and first off... It was a cheapish one at $20. It seems to be working though, and here's the read out.Quote:
Originally Posted by Pedro_The_Swift
https://www.aulro.com/afvb/images/im...017/02/715.jpg
While I was driving the Short term and long term stayed jammed at that minus position on bank 1, while the position on bank 2 seemed to stray between +5 and -5.
So does this mean my 02s on bank 1 are shot?
Swap them and see what happens.....
I swapped them over, and the problem didn't follow the sensor...Quote:
Originally Posted by ballbag
What's weird is there's a short/long fuel trim dial for each bank in the torque app, and then also one which is just "Fuel Trim Bank X Sensor X"
Both banks in that dial seem to be reading correctly, it's only the short term/long term dials which are faulting...
Anyone with any other ideas?
All your misfires listed above are on the RHS (driver's) ignition coil pack. You state the coils and leads were replaced, so check for loose ignition leads and loose signal wire (ensure retaining clip is in place).
While you're at it make sure the idle control valve signal wire is connected properly. Fuel pump is another possibility but given misfires seem confined to one coil I'd chase that first.
just some housekeeping,, depending on how unlucky a photographer you are,, the small green light in the ACCEL guage should be present in all--- not flashing green, not live data. Should be car symbol and wifi symbol as well, wait till they all stop flashing.
$20 is fine though it took me two replacements to receive a dongle that actually worked, so theres that as well.:angel:
It could be your OBD reader.
Bank 1 which is on the passenger side and contains the odd cylinders shows that the PCM is reducing fuel - a lean command. Bank 2 shows no action on the STFT, eventhough there are reported misfires there - cylinder 3?
A misfire allows extra O2 to travel past the O2 sensor. STFT will react accordingly. There are plenty of youtube videos showing this.
Start again.
What are the current misfire codes if any. Are they still on both banks?
Concentrate on the bank with the misfires.
Bring up the O2 readings again and this time pull off a vacuum hose to introduce an air leak - does the STFT react? They should react. If not then your O2 sensors are bad - or the OBD is bad( cheap OBD readers are notoriously unreliable). If they react then move onto the energy of the spark.
You can buy fairly cheap spark testers that show how strong the spark is on each cylinder. Dont just pull off the lead and hold it against the block as this is a DIS system and you can cause damage in the windings of the coil packs. Check each pot to see if the coils can create a 1/2 inch spark - about 10KV. If the spark is strong on every cylinder then you can start to look for other evidence.
Report back when you have time.
My mistake - Bank 2 shows no real action eventhough there are reported misfires there - cylinders 2 and 8 - not 3 as 3 is on Bank 1.
I forgot to add - with multiple misfires you are not really going to find the answer in the O2 sensors. O2 sensors are not the cause of misfires
You need to think about what has been disturbed in the engine bay over the last year. You need to look for any wiring that is rubbing on the chassis or not put back in the P clips - especially the wiring from the Crank and Cam sensors.
Lastly if your mechanic does not have a good USB oscilloscope then I would find someone else. You need to find someone who can check the waveforms coming from the Crank and Cam sensor plus primary and secondary ignition waveforms.
A good operator will have a 4 channel scope and be hooked up fairly quickly. He can capture the input waveforms of the sensors and the outputs from the PCM. He can quickly compare the waveforms against good known waveforms in a worldwide database. He could diagnose your problem very quickly - no more guessing. Ask around and find someone who has this gear.
For an example of how powerful this sort of diagnostics is compared to OBD - see the image below for a capture of a crank and camshaft signal that are slightly out of sync and causing multiple misfires. This problem has nothing to do with O2 - although they were reacting to the misfire.
Any small dropouts in such complex waveforms will create a distorted waveform that cannot be interpreted correctly by the PCM - hence the need to check wiring.
OBD codes can be very misleading when misfires occur and lead you up the garden path. OBD would never be able to correctly identify the misalignment of cam and crank signals as accurately as an oscilloscope image - it would just report multiple misfires in your generation of engine computer.
It would be worthwhile to find someone with the correct equipment if you find no wiring issues. Good luck.
BTW: I have this equipment and am currently chasing signal dropouts on one of my own cars today.