2015 Forester 2.0

[robintay70]

On 3/14/2021 at 11:41 AM, Orixy said:

 

Hi Robin, i decided to do a custom tune to try remediate the issue, improve fuel consumption, and also improve performance. I'm happy to report that the tuning did make the "heatsoak" issue quite minimal and improved performance by leaps and bounds, FC still monitoring but from last 2 tanks the FC improved from 8-9km/L to 9-10km/L. 

 

I did discuss with tuner about the heatsoak issue before the tuning and he had taken it into consideration while tuning. 

 

Sharing here for everyone to consider  🙂

 

HI Orixy, thanks for sharing about your tuning experience. Very tempting indeed esp for the fuel consumption, as I do 50% city 50% highway.

Before my servicing last week, i was clocking 6.5lm/l. After servicing, I am hitting 7.5km/l

With the 98 petrol prices hitting nearly $3, need to go easy on usage of the car.

Can you share with me / pm the price of the tuning and the tuner's name? 

Need to see how i can help my fuel consumption.

Thanks again for sharing this info, it came at the right moment!

 

 

[Shibadog]

On ‎1‎/‎17‎/‎2021 at 3:53 PM, Orixy said:

Hi guys! Long time since i had last posted.

Past few months I've noticed a worrying issue on my 2017 FXT. Whenever the car has been driven for a while and the engine and drive train are hot, the car will almost always become sluggish to drive. Moving off from stationary, the acceleration will be like absent during the initial rpm until i press harder then it will accelerate albeit in a reluctant manner.

This happens in I or S mode, i seldom uses S#. My engine is not tuned, and i always use Esso 98 petrol and occasional Shell vpower. I would also notice the ignition advance multiplier (IAM) would drop, which indicates some engine knocking/pinging.

This only happens whenever car has been driven quite a while, especially during a trip with lots of starts & stops. On the other hand, if it's a 1hr trip to office, then evening time from office back to home in 1hr, then no such issue since car had ample time to cool down in between and the trip didn't involve starts & stops. Appears to be some heat soak issue to me but i can't pinpoint to anything specific. Not sure if any FXT owners here also experiencing similar issues?

From Googling, i found similar findings from USA Subie Forester forum:

https://www.subaruforester.org/threads/2016-mild-surging-feeling-under-light-acceleration.589266/unread 

 

Some suggested could be air leak at the turbo pressurised side as the hose clamps expand from the heated engine and components. So i checked my upgraded Breeze clamps and tighten all of them and still no improvement.

As of now i have no idea what is causing this and the issue is replicated consistently. No solutions in sight too. If you know anything i dont, pls give some good advice! Thanks in advance.

this does sound like the classic Subaru problem of heatsoak, primarily at the tmic. It can also be exacerbated by the air intake type and location. That's why some sti cars come with a tmic  water spray. Basically the tmic is overheated and unable to remove heat from the hot (post-turbo) air. Hot air goes into the combustion chamber which gives less energy and also more prone to knocking. To overcome this, the car ECU pulls back ignition timing, which results in (temporary) loss of power until things cool down and function properly again.

[Stratovarius]

On 3/14/2021 at 10:26 PM, Jasonloke13 said:

Hi bros I intend to do a custom tune soon and heard quite a few comments that Forester XT is not advisable to go on a dyno run as our CVT gearbox might not be able to take it thus would like to hear your advice please. Currently I had shortlisted BMS Tuning as heard quite a number of good reviews. 

You can go for a dyno tune if you want the graphs and exact peak hp/Nm numbers. But street tune will be more practical. From what i know, the CVT is not advisable to go beyond 450Nm. If you are not going for stage 1.5 or above, meaning just doing stock tune, you should be fine.

I went with Advanced tune, not advertising for them though. if im not wrong, they sometimes do tuning for BMS. But either will be fine. Good luck. 

[Stratovarius]

9 hours ago, robintay70 said:

HI Orixy, thanks for sharing about your tuning experience. Very tempting indeed esp for the fuel consumption, as I do 50% city 50% highway.

Before my servicing last week, i was clocking 6.5lm/l. After servicing, I am hitting 7.5km/l

With the 98 petrol prices hitting nearly $3, need to go easy on usage of the car.

Can you share with me / pm the price of the tuning and the tuner's name? 

Need to see how i can help my fuel consumption.

Thanks again for sharing this info, it came at the right moment!

 

 

50-50 should do around 9-10km/litre. At least for me. My short burst in the neighborhood will yield around 6 to 7km/l. 

I dont see a vast improvement in FC after tune. But like what ah keong told you, a tune will resolve the sluggish issue which i think is more of a priority. You should give it a shot. any performance or FC gain will be a bonus. 

[Stratovarius]

9 hours ago, Shibadog said:

this does sound like the classic Subaru problem of heatsoak, primarily at the tmic. It can also be exacerbated by the air intake type and location. That's why some sti cars come with a tmic  water spray. Basically the tmic is overheated and unable to remove heat from the hot (post-turbo) air. Hot air goes into the combustion chamber which gives less energy and also more prone to knocking. To overcome this, the car ECU pulls back ignition timing, which results in (temporary) loss of power until things cool down and function properly again.

Will changing a bigger TMIC resolve this issue? 

[Shibadog]

29 minutes ago, Stratovarius said:

Will changing a bigger TMIC resolve this issue? 

usually it will mitigate or delay onset of this issue but it probably depends on the specific tmic - size, efficacy, construction etc

at the end of the day, it's still sitting on top of a heat source and needs airflow to cool down

[inlinesix]

52 minutes ago, Shibadog said:

usually it will mitigate or delay onset of this issue but it probably depends on the specific tmic - size, efficacy, construction etc

at the end of the day, it's still sitting on top of a heat source and needs airflow to cool down

No wonder i saw FMIC for Subaru.

[Orixy]

12 hours ago, robintay70 said:

HI Orixy, thanks for sharing about your tuning experience. Very tempting indeed esp for the fuel consumption, as I do 50% city 50% highway.

Before my servicing last week, i was clocking 6.5lm/l. After servicing, I am hitting 7.5km/l

With the 98 petrol prices hitting nearly $3, need to go easy on usage of the car.

Can you share with me / pm the price of the tuning and the tuner's name? 

Need to see how i can help my fuel consumption.

Thanks again for sharing this info, it came at the right moment!

 

 

I've PMed you 🙂

[Orixy]

11 hours ago, Shibadog said:

this does sound like the classic Subaru problem of heatsoak, primarily at the tmic. It can also be exacerbated by the air intake type and location. That's why some sti cars come with a tmic  water spray. Basically the tmic is overheated and unable to remove heat from the hot (post-turbo) air. Hot air goes into the combustion chamber which gives less energy and also more prone to knocking. To overcome this, the car ECU pulls back ignition timing, which results in (temporary) loss of power until things cool down and function properly again.

 

Thanks for sharing. Yah, agreed with your assessment on heatsoak. I did a DIY water spray on my tmic for my FXT, poor man's design and method though. 😛

I guess the tuning worked around this by giving back ign timing and using slightly more fuel to elevate the heatsoak issue and timing retard.

[Stratovarius]

1 hour ago, Orixy said:

 

Thanks for sharing. Yah, agreed with your assessment on heatsoak. I did a DIY water spray on my tmic for my FXT, poor man's design and method though. 😛

I guess the tuning worked around this by giving back ign timing and using slightly more fuel to elevate the heatsoak issue and timing retard.

U tap from the wiper spray line? Lol.

 

[Orixy]

Just now, Stratovarius said:

U tap from the wiper spray line? Lol.

 

Haha spot on! I tap from rear wiper water spray line, cos rear wiper spray usually low usage anyway. 

[Stratovarius]

13 minutes ago, Orixy said:

Haha spot on! I tap from rear wiper water spray line, cos rear wiper spray usually low usage anyway. 

Lol. That's innovative. 

Sj5 should have the traditional bonnet scoop for efficient cooling.

[shutterbox]

2 hours ago, Orixy said:

 

Thanks for sharing. Yah, agreed with your assessment on heatsoak. I did a DIY water spray on my tmic for my FXT, poor man's design and method though. 😛

I guess the tuning worked around this by giving back ign timing and using slightly more fuel to elevate the heatsoak issue and timing retard.

I wonder if removing that plasti engine cover would have given more cooling to the engine

[Colin03]

I always remove all unnecessary cover in the engine bay.

As believe has a better cooling effect.

Just like the L plate private vehicle always unlock their bonnet when the student practicing the parking.   

[Shibadog]

4 hours ago, Orixy said:

 

Thanks for sharing. Yah, agreed with your assessment on heatsoak. I did a DIY water spray on my tmic for my FXT, poor man's design and method though. 😛

I guess the tuning worked around this by giving back ign timing and using slightly more fuel to elevate the heatsoak issue and timing retard.

nice.

I also had a tmic water spray on my fxt, taken from an euro spec sti (5L tank mounted in boot). Tank was too small for sepang duties but more than sufficient for local driving.

I wonder if the SJ tmic gets more dirty over time due to lack of a bonnet scoop. Dirt on the tmic fins will reduce the cooling efficiency even when nice cool air is flowing through it. For old school subies with a hood scoop, it's a lot easier to clean it at the same time as washing car - just lightly spray with car shampoo n rinse off. They do tend to collect more leaves though LOL

[Elginlye]

Hi,

Are there other Subaru stockists besides following 2? I need to get the rear right garnish.

Lesun Auto Parts

Blk3018, #03-117 Ubi Rd. 1, Singapore 408710

Tel: 6846 8655 (Wee)

 

Guan Auto Engineering

2A Veerasamy Rd, s(207306)

Tel: 62963520
111 Kaki Bukit Ave 1, Shun Li Industrial Park, Singapore 415990
Tel: 67471230

 

 

[Shibadog]

17 minutes ago, Elginlye said:

Hi,

Are there other Subaru stockists besides following 2? I need to get the rear right garnish.

Lesun Auto Parts

Blk3018, #03-117 Ubi Rd. 1, Singapore 408710

Tel: 6846 8655 (Wee)

 

Guan Auto Engineering

2A Veerasamy Rd, s(207306)

Tel: 62963520
111 Kaki Bukit Ave 1, Shun Li Industrial Park, Singapore 415990
Tel: 67471230

 

 

Lesun has moved to blk 3016

JAE Auto is still at blk 3018 (ground floor). They also stock Subaru parts.

[Orixy]

6 hours ago, Shibadog said:

nice.

I also had a tmic water spray on my fxt, taken from an euro spec sti (5L tank mounted in boot). Tank was too small for sepang duties but more than sufficient for local driving.

I wonder if the SJ tmic gets more dirty over time due to lack of a bonnet scoop. Dirt on the tmic fins will reduce the cooling efficiency even when nice cool air is flowing through it. For old school subies with a hood scoop, it's a lot easier to clean it at the same time as washing car - just lightly spray with car shampoo n rinse off. They do tend to collect more leaves though LOL

Wouldn't a bonnet scoop let in more dirt since it is more direct? I do clean my tmic once a year using those carb cleaner to clean both interior and exterior.