New to Tuning - 3rd log. VY V6 NA no Mods (YET)

[Retr0]

Hi Everyone,

New to the world of tuning, done plenty of reading on the subject now.

As stated in the topic, Car is a N/A VY Commodore V6, I have grabbed a spare PCM and uploaded the1's Enhanced Bins to the car.

So upon my first log I noticed there was a reasonable amount of knocking going on, the car has done over 300,000km's now but I just thought it was because I'm running 91 octane in the tank, I have since sprayed a can of Subaru upper engine cleaner into the intake as it was suggested that a car of that many km's probably has hot spots on the valves (Thanks Antus for the suggestion!).

Upon spraying the stuff into the intake though I noticed the bottom of the intake has was cracked! so I quickly drove round to the wreckers and grabbed a new hose ($13).

The attached log is what I logged earlier this evening, the only changes are upper engine cleaner and new intake pipe, not running higher octane fuel yet as I haven't quite used up the last of the 91 that's still inside the tank. On my first and second log runs (can upload those runs too if anyone is interested) the air intake temp was 35C, the run this evening it's down to 11C! so that's a big improvement already .

So cruising at 100km is where I notice a lot of knocking going on, the AFR ranges from 14.7 to 17.0, it drops to 12.8 when I plant it so I'm assuming thats when PE kicks in and adds some fuel. Not sure what the difference between Acceleration enrichment is and Power Enrichment yet, I have thought about playing with PE and dropping the AFR number down to 12.5?

I also noticed late into the log run that the AFR target was randomly jumping right up to 25.something and then dropping right back down again, not sure what the deal is there.

Any thoughts and suggestions would be greatly appreciated!

[Wade]

I haven’t really noticed much to be gained with the na v6’s. There pretty good to start off with. You can play around with some transmission settings that makes em feel a bit more responsive. Other than that just go over the car and check it’s health

[Retr0]

Thanks for your reply Wade.

Just remembered, when doing that log run dtc code 76 c/l integrator failure was set, when I seen it I cleared it and it hasn't since returned, but what is it? I can't find anything definitive on the web and I'm still fishing around the house for the workshop manual.


Cheers,
Retr0

[immortality]

When the AFR's jump up to 25 the pcm has cut the fuel during engine braking/retard. This is normal.

AE or acceleration enrichement works of the TPS, basically when you plant boot the PCM injects in extra fuel to cover what would otherwise be a flat spot or lean out because the MAF or MAP sensor has a slight delay in seeing that increase.

17:1 would be lean cruise. Most people here drop that down to about 15.4:1 as that is where the best fuel burn seems to happen. If you are getting lean cruise miss or knock it may indicate the ignition needs looking at or you may have a sick injector. A lean condition in the cylinder is harder to ignite so will show up weaknesses in the fuel or ignition systems.

[Retr0]

You can play around with some transmission settings that makes em feel a bit more responsive.

Been doing some more logging now I've got 95 octane in the car. 1-2 gearshift time is 1.4-1.6 seconds, 2-3 is pretty good it's at 0.45 seconds. I've read the1's quick pdf guide on how to tune the auto but I'm still a bit confused, do I change the adjust the force motor pressure table or do I adjust the "force motor - pressure added for 1-2 upshift"?

17:1 would be lean cruise. Most people here drop that down to about 15.4:1 as that is where the best fuel burn seems to happen. If you are getting lean cruise miss or knock it may indicate the ignition needs looking at or you may have a sick injector. A lean condition in the cylinder is harder to ignite so will show up weaknesses in the fuel or ignition systems.

That's interesting, if there's a sick injector will this show up in any of the logs? The ignition leads I don't think have ever been replaced so they are on the to do list in a few weeks (tax time).

How to I translate the numbers in the lean cruise table into an AFR? What are the numbers in the lean cruise table anyway is that CYLAIR?

[immortality]

No, the O2 sensor only reads the bank as a whole so if lets say one injector is sick (partially clogged) during closed loop mode it will increase the PW on all 3 injectors to bring the whole bank back to where it wants. On our Calais I had slight difference between the LH and RH fuel trims, fitting new injectors seemed to solve that issue and with new spark plugs and leads fitted she's running better than ever.

Seeing as you suspect you have really old leads I would suggest plugs and leads are your first port of call along with a good overall service. Not much point trying to tune unless you know all the basics are in order. I would also do the fuel filter, clean the MAF and the TB and oil and filter.

The numbers in the lean cruise table are a correction factor, so lets say for arguments sake the number in the table is 2, closed loop operation means we are targeting 14.7:1 AFR, when it goes into lean cruise mode it will then target 14.7 + 2 (correction factor from lean cruise table) to give 16.7:1 AFR.

[Retr0]

No, the O2 sensor only reads the bank as a whole so if lets say one injector is sick (partially clogged) during closed loop mode it will increase the PW on all 3 injectors to bring the whole bank back to where it wants. On our Calais I had slight difference between the LH and RH fuel trims, fitting new injectors seemed to solve that issue and with new spark plugs and leads fitted she's running better than ever.

Very interesting information! 2 years ago I "serviced" the fuel injectors, well... I followed this guide on the commodore forums: https://forums.justcommodores.com.au/th ... cs.222822/ whether that was the right or wrong thing to do though is another interesting fact all together I guess.

Did you just buy replacements off ebay like these? https://www.ebay.com.au/itm/6x-Fuel-Inj ... SwFFZbDQnE I was looking on eBay last night and found these: https://www.ebay.com.au/itm/Holden-VN-V ... SwHYpaKSY~ not sure what the standard injector specs are, not sure if injectors are kinda those dodgy oxygen sensors for $40 that are going around on eBay too.

I'll have a look at my latest log at the fuel trims for a look see.

Seeing as you suspect you have really old leads I would suggest plugs and leads are your first port of call along with a good overall service. Not much point trying to tune unless you know all the basics are in order. I would also do the fuel filter, clean the MAF and the TB and oil and filter.

What do I use to clean the MAF? I've got electronic cleaning solvent from jaycar? I'm assuming that sensor has a cleaning process similar to an oxygen sensor?

The numbers in the lean cruise table are a correction factor, so lets say for arguments sake the number in the table is 2, closed loop operation means we are targeting 14.7:1 AFR, when it goes into lean cruise mode it will then target 14.7 + 2 (correction factor from lean cruise table) to give 16.7:1 AFR.

Now that's starting to make sense, I thought the numbers where an afr target but in some other figure!.

[immortality]

I bought replacment injectors from The1 one this forum as a flow matched set.

Unfortunately replacing the filter baskets and O rings and spraying injector cleaner into the top doesn't clean out the actual working parts inside the injector which is the most important part.

[Retr0]

I bought replacment injectors from The1 one this forum as a flow matched set.

Unfortunately replacing the filter baskets and O rings and spraying injector cleaner into the top doesn't clean out the actual working parts inside the injector which is the most important part.

I'll shoot him a pm. When I did it I actually never put injector cleaner through the petrol tank, could always do that as a temporary solution?

Here's my latest log from the weekend, the differences between this and the last log is replacement intake pipe and 95 octane fuel, it has a mixture of 60km cruising, some 100km cruising, and I tried planting the foot down every now and again too. The only thing that really stands out to me is the right hand o2 sensor is generally a couple of cross counts behind the left hand o2, I have learnt recently that those things are a serviceable component of around 160,000km intervals, these replacements are on my buying list at tax time: https://www.ebay.com.au/itm/Pair-4-wire ... SwkLJbJs2t note that this actually isn't the right part, mine are the 2 wire, supercheap auto have the bosch branded ones in 2 wire for $140 trade.

[Retr0]

So I replaced the spark plug leads yesterday with eagle elimintor performer series 8.0mm leads ($99 trade supercheap auto online).

I think the knocking is better, but is still there.

Having a bit of a play today whilst logging, the knock is most prominent under light acceleration between 1500-2500 rev range. If I accelerate hard the knocking is virtually non-existant.