Car very sluggish especially when engine hot or in jam.

[ironheart]

When driving off from cold start, the car is very responsive but as the engine gets warmer, it becomes very sluggish.

And at times, it takes a long while to react after I step on the accelerator and the rpm builds up very slowly.

Sometimes I even have to lift my foot off as the rpm doesn't react, seems like no fuel going into the engine and step again before the rpm is willing builds up.

This is becoming dangerous because I got stuck a few times while turning at junction or in heavy jams, with the car crawling like a snail refusing to build on rpm.

I have observed that it only happens when the engine is hot.

Anybody face this problem before? Thanks

I have changed the plugs, air filter, engine mountings, ignition coils, clean throttle body, cvt fluid change, etc but the problem still persist.

[jonpaul0104]

When driving off from cold start, the car is very responsive but as the engine gets warmer, it becomes very sluggish.

And at times, it takes a long while to react after I step on the accelerator and the rpm builds up very slowly.

Sometimes I even have to lift my foot off as the rpm doesn't react, seems like no fuel going into the engine and step again before the rpm is willing builds up.

This is becoming dangerous because I got stuck a few times while turning at junction or in heavy jams, with the car crawling like a snail refusing to build on rpm.

I have observed that it only happens when the engine is hot.

Anybody face this problem before? Thanks

I have changed the plugs, air filter, engine mountings, ignition coils, clean throttle body, cvt fluid change, etc but the problem still persist.

My Yr05 latio sport CVT also has the same problem....so far even TCM also cannot detect any fault based on consult disgnostic result...so LLST.....rpm increases but speed dun...

It is so bad that even going up MSCP is also frightening as the car refuse to climb fast eg. IMM carpark, Taka carpark....I even got high beamed/horned many times.....

[archie_baby]

Perhaps you may want to consider enquirying with our resident mechanic, Kelvin.

[Kenneth82]

I also got similar problem that time and in the end, it was diagnosed that my engine mount was the primary fault.
Beginning of such symptoms, my dashboard got no vibration at all and sluggish from standstill and going up car park slopes.
When it became more serious, my dash board will vibrate at certain times.

After I visited Kelvin, I changed my engine mount and do throttle cleaning + reset the ECU settings.
Right now no more problem but just 2 days ago when I pump Esso 95 after 2 tanks of Esso 98, my engine became slightly noisy with the "klang klang" sound aka knocking sound when accelerating at low speed or going upslope.

Luckily got no performance issue but still remains to be one of Latio's defects when u pump low octance petrol.

[Enzoni]

i dun think the engine mounting will cause this, i suppose this problem only occur in CVT latio?

i have encountered a few times and i noticed it happened after i let my car 'roll' for too long in jam or 'balancing' on slope too much meaning engage 'D' gear and let go both accelerator and brake

but it recovered after losing power for a short while, quite scary

[ironheart]

I do frequent Kelvin pretty often. Like I have said, so far in one year I have already at least changed or done the following, all parts are new.

1. CVT Fluid
2. Original Spark Plugs
3. 4 x Ignition Cable
4. All engine mountings
5. Aircon compressor
6. Rear brake pads and drums
7. Air Filter
8. Amaron 45A battery
9. Throttle body cleaning
10. Engine and radiator flushing

The problem still exist every now and then especially in heavy jam or when restart after short interval after a long drive say 25 to 30 mins.

Seriously dunno what is the problem, the car will not stall, idling rpm also perfecting normal, it is only when step on accelerator, the car like constipated, move off damn slowly with rpm staying at around 1000rpm, refusing to climb despite foot already floored the pedal. After a few seconds then engine speed willing to build up..........slowly

It is very dangerous with such condition as you don't know when it will relapse, imagine it happens when one is turning and in the middle of a busy cross junction.

Sigh...

[Jazz]

CVT gearbox going up the lorry I guess.


If changed CVT oil, remember to bleed fully else air trapped may also affect performance.

[ironheart]

I dun think it is the CVT problem as yet as when the sluggishness happens, it feels like not enough petrol going into the engine and takes quite a a few seconds to slowly revs up. Once it manages to sluggishly rev past 1800 rpm, the engine comes alive and back to normal again.

[pizzaboy]

Replace ur fuel pump & fuel filter see hw it goes aft dat

[Jazz]

Not enough of fuel to the engine will cause jerking, same like out of petrol situation.

Anyway, you can take note of pizzaboy suggestions.

[jonpaul0104]

Replace ur fuel pump & fuel filter see hw it goes aft dat

Latio fuel pump and filter change quite ex....i think cost abt $500+ as latio type is in-tank....

But if can solve the problem, i dun mind changing even though my car left 2yrs

[dsrio]

to TS, do you have any aftermarket gadgets connected to your accelerator? such as pivot 3-drive etc? if yes, remove them and monitor again.

[bb88wa]

just my 2 cents..

on a hot day, naturally, all cars will be a little sluggish.. this is caused by the hot air within the engine compartment... there is nothing much we can do to fix this..

This will be felt especially so if you are using an open pod air filter... (modified air filter)

Try to monitor your car behavior at night, if there is no sluggishness felt.. this theory is correct..

Cool air = more power = smoother car = etc etc etc..

[jonpaul0104]

just my 2 cents..

on a hot day, naturally, all cars will be a little sluggish.. this is caused by the hot air within the engine compartment... there is nothing much we can do to fix this..

This will be felt especially so if you are using an open pod air filter... (modified air filter)

Try to monitor your car behavior at night, if there is no sluggishness felt.. this theory is correct..

Cool air = more power = smoother car = etc etc etc..

for my case, my car is fully stocked....and happen both nite & day......

the sluggish is not just a little but damn frightening type.....imagine getting horned & high beamed while climbing MSCP slope eg. IMM, Taka....not very steep type....

But when going up Genting did not experience it.....climb Genting easier and better than Kia....

So only difference is the traffic jam when start stop start stop......

[wooks]

I'm on AT, using shell Vpower, using Castrol engine oil, without modification, good acceleration.  Cool whether confirmed better performance.

[RB20DET]

Actually, when engine oil boil up to certain temp engine performance will drop. Unless your engine oil can take high boiling point ... but in return your engine will be very thin and you might need to change every 5000-7000 range.

Same thing to GB oil.