SV6 OTR & Tune Issues

[Flurocity]

Hello everyone,

I recently started having issues with an OTR and dyno tune done to my 2015 VF SV6 and was hoping to draw upon your expertise, to help me find the issue.

I've recently noticed that the car is acting sluggish, has a strong fuel smell from it's oil, has a rough idle at times, has an egg smell from the exhaust at times, and also has a rattling sound upon acceleration. I initially thought that the increased air had caused the cat to break off and cause the rattle.

But after speaking to a mechanic friend. They said that the issue is probably a restriction caused by having the stock cats. He said that the stock cats are restrictive and since the exhaust is not leaving the engine, it builds up within it causing fuel not to be burnt and the tappets to work harder, hence the rattle sound and fuel in the oil.

I'll be taking the car back to the tuner for them to look over. When i spoke to them, they assured me that the fuel smell in the oil is normal, which i don't think is correct?

If anyone is able to point me in the right direction, i'd highly appreciate it.

Thank you.

Other details:
- Always used 98 fuel
- Car was serviced by Holden prior to OTR and Tune in March this year
- OTR and Tune was done in June

 

[Forg]

Your mechanic mate could be paraphrasing … but what you’ve said he’s said definitely isn’t what’s happening.

 

[Flurocity]

Your mechanic mate could be paraphrasing … but what you’ve said he’s said definitely isn’t what’s happening.

Thanks Forg, Any ideas as to what might be going on. I'm hoping that the tuners are good enough to identify what's going on. Bit worried if they come back saying that everything is all good, when it doesn't seem like it.

 

[Forg]

Sorry, I’m not enough of an expert to say; however if the tune was done properly then it was done with the flow allowed by the cats; hence the cats being stock won’t be the cause. It could be a failed cat or something like that, though, I guess … although that doesn’t explain fuel in the oil … dunno what would get fuel in the oil.

 

[Not_An_Abba_Fan]

A 3.6L V6 will never outflow the factory cats. There are only 3 cylinders going through each cat.

Sounds more like a miss and unburnt fuel is getting past the rings into the sump.

 

[RevNev]

I recently started having issues with an OTR and dyno tune done to my 2015 VF SV6

I've had a bit of a fiddle with my SV6 ute and the stock tune is pretty good, much better than a stock V8 tune. There's a small window between 3800 and 5600 rpm where you can add a couple of degrees of timing but other than that, I'd leave the stock tune alone and an OTR will be fine with the stock tune. I'd put the stock tune back in and see how it runs as the modified tune may be at fault depending on what was altered.

 

[harrop.senator]

I've had a bit of a fiddle with my SV6 ute and the stock tune is pretty good, much better than a stock V8 tune. There's a small window between 3800 and 5600 rpm where you can add a couple of degrees of timing but other than that, I'd leave the stock tune alone and an OTR will be fine with the stock tune. I'd put the stock tune back in and see how it runs as the modified tune may be at fault depending on what was altered.

Did you turn the engine torque management off to get full throttle under 3600 or so? That's usually the biggest gain to be had with the 3.6's. I know on vz and ve in the early one anyway all the scaling was different on the throttle. 100% pedal with like 50-60% throttle opening until it comes above a certain rpm. With the older ones you may gain 8-10 kW up top. But another 30 or so off idle and over 100 more nm.

 

[RevNev]

Did you turn the engine torque management off to get full throttle under 3600 or so? That's usually the biggest gain to be had with the 3.6's. I know on vz and ve in the early one anyway all the scaling was different on the throttle. 100% pedal with like 50-60% throttle opening until it comes above a certain rpm. With the older ones you may gain 8-10 kW up top. But another 30 or so off idle and over 100 more nm.

No, I haven't played with torque management yet and I was focused on ignition timing and air/fuel ratio in this particular SV6 that was quite optimised for a stock tune. They're lazy on throttle down low compared with an FG Falcon but they rev harder and better in the upper RPM range. Thanks for the torque management tip, I'll try that and may sharpen the throttle response up a bit.

We've always had 6 cylinder Falcon's and V8 Commodores with the idea the V6 engine was poor performing junk until swapping my old BA Falcon work ute for a VF2 SV6 ute, I discovered the LFX V6 was far better than I anticipated and they go ok effortlessly revving to 6500rpm if you stand on them. I've got to really like the SV6 ute as a daily driver, it's a good car!