RvR 4G63T engine dies off when comes to a stop

[cfphoon]

Hi guys. I'm having this problem with my engine for quite some time and I still can't resolve it. I'm currently running a standard Mitsubishi RvR 4G63T engine in my wira and the problem is the engine often dies off when coming to a stop while running with the AC on. Without on AC will dies off also but not that frequent. Recently just replaced stepper motor but still the same. Anyone faced this problem before?

 

[vr2turbo]

What if you tune the idling higher?

 

[parakey]

Is this manual or auto? Engine stalls when you're braking down from a fast speed, right? When braking from a slower speed, it doesnt stall?

 

[cfphoon]

What if you tune the idling higher?

Right now the idling is around 900rpm.if i tune it higher then it would be 1k plus rpm and its just wasting fuel

 

[cfphoon]

Is this manual or auto? Engine stalls when you're braking down from a fast speed, right? When braking from a slower speed, it doesnt stall?

It's a manual. Braking slow speed is fine but recently I noticed that the engine stalls too without on ac. Coming downhill to a stop would make the engine stalls too

 

[gunnerzz]

I'm not an expert but when we brake to slow down, couple of things happened at the same time;
1.Throttle body closes as we lift off the gas
2.Brake servo uses the vacuum from the intake.
3.RPM drop which causes alternator current supply to be lower.Alternator works like the dynamo on our bicycle,the faster it spins, the higher the amp it produce.

I would take a look at the vacuum hose to see if there is any leak, then check the alternator if its supplying steady current at low rpm, then the air flow sensor.

 

[parakey]

I'm not an expert but when we brake to slow down, couple of things happened at the same time;
1.Throttle body closes as we lift off the gas
2.Brake servo uses the vacuum from the intake.
3.RPM drop which causes alternator current supply to be lower.Alternator works like the dynamo on our bicycle,the faster it spins, the higher the amp it produce.

I would take a look at the vacuum hose to see if there is any leak, then check the alternator if its supplying steady current at low rpm, then the air flow sensor.

What he said .. but also check the grounding as well

 

[cfphoon]

I'm not an expert but when we brake to slow down, couple of things happened at the same time;
1.Throttle body closes as we lift off the gas
2.Brake servo uses the vacuum from the intake.
3.RPM drop which causes alternator current supply to be lower.Alternator works like the dynamo on our bicycle,the faster it spins, the higher the amp it produce.

I would take a look at the vacuum hose to see if there is any leak, then check the alternator if its supplying steady current at low rpm, then the air flow sensor.

I'll definitely check again on the vacuum hose but I doubt it got leak.. How to check the air flow sensor?

 

[cfphoon]

What he said .. but also check the grounding as well

Ok thanks.

 

[gunnerzz]

I'll definitely check again on the vacuum hose but I doubt it got leak.. How to check the air flow sensor?

Easiest way is to swap the sensor or using a computer scan tool.
Hard way is to use a multimeter but u must know the normal figure first,which most of us dont know.

When u are stationary with aircond on or off ,have u tried pressing the brake pedal multiple time and does it affect your idling?
If not then i suspect its poor wiring contact which include grou ding. Can happen.

 

[vr2turbo]

Yup, current load, vacuum all play a part. Mine last time with air con off is ok, but with air con on it drops until very low rpm, and sometimes dies off. Change FICD work a while then FICD konk again, seems common problem. Then add manual ficd from kembara, modded it on....lol