pcmhacking.net

Hello all I hope I can find some advice.
I have a 2000 VS ute with a 16199728 CXAJ PCM
VX V6 ecotec, EGR removed and blocked in the TB, using VS exhaust manifolds.
New purge valve solenoid, air cleaner, injectors(777), spark plugs, intake gaskets, coolant sensor(gauge), intake tube, O2 sensors.
I have done a compression test 185 to 195 psi, checked for intake leaks multiple times, checked fuel pressure(40to45psi), checked fuel pressure regulator with a vacuum pump, cleaned IAC, TB, PCV, tested coils. and bought a refurbished recalbrated MAF.
I have done the O2 sensor earth trick in the PCM plugs.

I have Tunerpro V5 and I'm using VS_V6_$51_Enhancedv1.4b.bin, VS_V6_$51_Enhancedv1.4d.xdf, VS_V6_$51_Enhanced.adx.

The motor quit pulling after 4500 rpm today so I put in a CAT test pipe using a 50mm hole saw, pulls all the way to redline now.
Now the problem I have had since I bought the car, it runs pig rich all of the time. Black smoke at idle and the O2 readings in the 800 to 900mv range. The spark plugs confirm the rich state being totally covered in black soot, but they are dry. When I drive the car with tunerpro plugged in the O2 sensors are showing rich, the STFT and LTFT are showing negative numbers but it still runs in the 800 to 900mv range.
When it's warming up the O2 cross counts are working but after warming up that stops. On the freeway the BLM turns off and the the O2 readings drop from 800 to 900 range down to 4MV. They come back up if I change the throttle position, but will always go back down to 4mv. With that said the spark plugs will still be covered in black carbon.

I am lost as to what to do next, I have hours of logs during all the changes I have been making but can't make sense of it all because nothing seems to be making much of a change. The 1 thing that seemed to clean up the idle before the MAF sensor purchase was I stuck a hair drier in the air filter lid about 75mm away from the intake charge pipe opening turned on high and the black smoke seemed to go away. I have been around cars and worked on them all my life as a hobby, but this is the first time I have actually tried to work with EFI.

So the question I will start with is am I using the right BIN, XDF and ADX?

Something else I should add is I'm using the VR VS Holden service manual for all the checking and testing I have done.

What MAF are you using?

Does the engine try to go into closed loop mode at all?

Hi immortality
Thank you for replying, it does go into closed loop and the MAF sensor is a factory genuine unit. I can take a pic of it if that would help.

I'd suggest sorting the exhaust issue first, if the exhaust is blocked it's going to screw with the tune.

Next, make sure there are no exhaust leaks before the O2 sensors as this will make the reading go off.

Then look for vacuum leaks between the MAF and engine/intake. Clean intake filter and clean the MAF (although I would expect a lean condition if these were dirty).

Is the IAT sensor connected and reading correctly? (when the engine is cold before first start both the IAT, ECT should be the same as the ambient air temp).


When you are cruising down the motorway it will be going into lean cruise mode so I would expect the O2 sensor readings to drop.

The exhaust is sorted, my week attempt at humour is confusing. The motor prior to today always revved well but I did suspect there might be an issue with the cat because I could smell it after a drive. Today when I tried to rev it while driving it wouldn't rev past 4000 rpm so I dropped the exhaust and knock out the stuff in the cat and went for another drive and it would rev well again. I haven't found any vacuum leaks between MAF and the intake, new intake pipe, new filter recalibrated MAF. As for the IAT it seems to around ambient to only a few degrees above ambient temp at all times. When I look at the log when I drove to work in the middle of the week 2 seconds into the log it shows ECT to be 12.50 and IAT to be 9.5.

Lots of raw fuel down the exhaust from running pig rich will melt down the CAT so that is most likely what killed it unfortunately.

You should copy over the injector data from the VT/VX tune into the VS (flow rate, injector constants and voltage offsets etc). The 777 injectors are slightly different but certainly not enough to cause the extra fuel you are describing but it can't hurt to get it as close as possible to begin with.

The ECT comes up to normal operating temp (the same or higher than the thermostat temp)?

What do you mean by "re-calibrated MAF" ?

The recalibrated MAF comes from a place called injectronics in the Melbourne area. They take your MAF clean it and recalibrate it. https://www.injectronics.com.au/. They actually do it as a change over. As for changing the injector data I would need a burner or an NVRAM wouldn't I? The car has a 16199728 CXAJ PCM now, I also have a 16199728 BWPJ that I had in the car briefly but it still ran pig rich. I should add that I have been working at this since Sept. after work and on the weekends. I have a VY that I drive most of the time but I need to replace it due to it having nearly 470k on it and it knocking a little and loosing oil pressure when it is at temp. and idling. Again thank you for your help.

OK, so you are on the stock memcal?

Honestly. I'd try swapping the MAF over from your VY and see what it does.

The one thing I'm not certain about is what deleting the EGR does without modifying the tune.

Yes stock memcal. The VY is an LS1 motor, but I have a VS SS ute with a 5 litre motor as well, and I did swap the MAF out of that with the V6 VS and it ran a little better then when it had the original MAF. That's why I bought the refurbished MAF. I agree about the EGR thing, I wasn't sure if that was playing into this problem. With that said the VS didn't have an EGR and the PCM is from a VS so the tune shouldn't be looking for EGR inputs I would think. What the previous owner has done is epoxy fill the hole in the throttle body where the EGR would have connected to, but I still wonder if it is not a part of the problem. In my eyes at this point is it really looks like too much fuel pressure but I checked that. What I did was put in a tee connector right after the fuel filter and ran a rubber hose under the car, up the firewall and out off the bonnet near the windscreen wiper. Then I added a pressure gauge and cable tied it to the wiper arm and drove around town abit. It didn't go over 45 PSI as far as I could tell. It didn't go below 40 either. I also connected a vacuum hand pump to the fuel regulator and started the car and at idle if I applied vacuum to the regulator the pressure would drop, so I thought it was working properly. I did plug the manifold port when I did this test.