The VN Great Escape

[Holden202T]

can you notice it driving ?

[ToyHicko]

Notice what?

That it is lean or the difference after changing the VE table. Not a great change Driving at this stage but only playing in only a small section of the Table. When i was in the Driveway hold a constant rpm/Throttle and changed the VE the RPM did increase without changing throttle position. After the small changes i had made to the table the Knock had disappear from Crusing at 100km/h which was there before. I've had Lean crusie disabled for sometime now just to rule that out too.

From the Log I've posted up and the WB VE adjust Spreedsheet I need to increase some cells to above 100 so I'm starting to think something else is not quite right. At WOT AFR was around 14 should be at 12.5 which could cause it to knock.

Need to Log more data to determine my problem as something has to changed to cause this a K&N airfilter wouldn't make this much difference.

Plan is to geting running "OK" safely then log as a reference before renewing fuel filter then go for a drive see if anything changes. If no then swap Regulator with a spare from dead engine i have and data log. Still no change then Injectors out of the dead 100,000km VN engine and Adjust Injector Rate. If no change the then well change the Tables to suit engine.

Jason

[yoda69]

Another possibility is low fuel pressure, and injectors having to stay open longer to deliver same amount of fuel.
Check fuel pressure and fuel filter as if this is blocked pressure may look OK, but when asked to deliver may drop off.

yoda69

[ToyHicko]

I'm hoping more of a poor spray pattern causing low efficency as currently going through fuel, one tank is gone in 350km. The other that I'm a little concerned about is the new fuel pump Isn't suppling the correct fuel pressure.

[ToyHicko]

Will just out of interest here I've just done a VE table adjustment calucation two different ways. One using BLM's and the other using AFR from the same log.

The AFR was worked out using Holden's 202 Spreed sheet was works on ratio between current and requested. The ratio is then multied by the current VE value. working it out his way calcuated a huge change was required.

Using BLM working on 100 divide by BLM value them multiplied that to the current VE value. Seems to be the wider using method on this site gave a far less change.


After running WB Learn the result looked simular to the result from BLM rather then AFR. So from what i can see the relationship between VE and AFR doesn't appear linear. Has anyone else encountered this?

Edit: Had BLM calculation wrong way around.

[ToyHicko]

Well after doing some reading I'm now confused my WB is giving me a lean reading but the BLM are tell the ecu to trim back fuel (now geting BLM of 85 which i believe mean reduce fuel by 15%) but still got ping. So next question is how do you check if a Harmonic Balance hasn't slipped. Is there a Timing mark or something i can using a timing light on?

[ToyHicko]

Well just checked Fuel pressure and is in spec 300kpa and holds for over 2 minutes on idle drops back to 250 as the spec i have state so safe to say the fuel system is OK.

Gees if a K&N filter can makes this much difference then how may other car out there have the same issues?

[VL400]

Yeah BLM of 85 is pulling 15% of fuel, fair bit! To roughly check your wideband cofig is in the ballpark and that both narrow and wide sensors agree, drive along in closed loop then check the log. The narrowband will swing either side of 450mV and the wideband should be swinging either side of stoich. Only thing is your gonna need to install a second bung, with the wideband at the tailpipe you wont see the swings.

Actually, with just the wideband installed are you simulating the narrowband from it?

[ToyHicko]

correct i am simulating a NB using the WB.

Also just tried another ECU made no difference.

[ToyHicko]

Now I'm just going crazy

Two log identical Cal/Bin Only thing that change between them was i pulled the spark plugs out to see what they looked like. One has BLM's all over the place other is around 100. Looking closely at these to logs there is a knock even when the AFR is spot on the Target so maybe it is a biuld up of carbon thats is giving me so much trouble.

I've attache the two logs from today.