car hard to start after a week of unused

[Kumweng]

I leave my car at car park for a week unused. last night I try to start me car. I crank many times and then finally started. The battery was strong. After start, the car vibrate a bit while. The RPM needle move up and down and dieing off again. AFter warm up, car back to normal.

What happen? ANy advise

[Ct3833]

Does not sound like due to unused, did you get the same problem after the engine is warmed up? 

it is bettrryou send it to a mechanic  for a check, probable cause can be fuel pump, injectors heads, spark plugs, high tension coils etc.

[Arogab]

You will need to tell us what car/model? How old, probably also know how the car is maintained. There might be many areas to identify

I never have this issue, my car is used only once a week. 5 years coming. Of course I tell you it is fully maintained by agent with 5 years warranty and full maintenance paid. So agent will never allow the issue to happen to me.

[ER-3682]

  On 9/24/2021 at 11:32 PM, Kumweng said:

I leave my car at car park for a week unused. last night I try to start me car. I crank many times and then finally started. The battery was strong. After start, the car vibrate a bit while. The RPM needle move up and down and dieing off again. AFter warm up, car back to normal.

What happen? ANy advise

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If old Car,most likely are Injectors Leaking,causing it ''Flooded''...

[Beregond]

  On 9/24/2021 at 11:32 PM, Kumweng said:

I leave my car at car park for a week unused. last night I try to start me car. I crank many times and then finally started. The battery was strong. After start, the car vibrate a bit while. The RPM needle move up and down and dieing off again. AFter warm up, car back to normal.

What happen? ANy advise

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If old car liao and u drive once a week only.  Dun need spend  so much money on it liao.

U mention after a while the car back to normal. So I guess  it will be extremely  hard for mechanic  to pinpoint the issue also.

Mostly  its try and error which mean putting your money at risk. 

High chance its fuel system or air intake.

Are u ok with stuff like changing the fuel pump try and see how first? 

 

[Contipro]

  On 9/24/2021 at 11:32 PM, Kumweng said:

I leave my car at car park for a week unused. last night I try to start me car. I crank many times and then finally started. The battery was strong. After start, the car vibrate a bit while. The RPM needle move up and down and dieing off again. AFter warm up, car back to normal.

What happen? ANy advise

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must be something faulty.

my longest is left for 4 weeks, start with 1 crank.No issue 

[Kb27]

  On 9/24/2021 at 11:32 PM, Kumweng said:

I leave my car at car park for a week unused. last night I try to start me car. I crank many times and then finally started. The battery was strong. After start, the car vibrate a bit while. The RPM needle move up and down and dieing off again. AFter warm up, car back to normal.

What happen? ANy advise

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Condensation, oily contaminants, left to coagulate, gel up, in the throttle body. blocks the idling air passage. Hence idling rpm not stable, engine may stall.

Once these are cleared, your engine go back to normal operation. It will repeat again, if you left it in cold storage for a long time.

[Stary]

  On 9/24/2021 at 11:32 PM, Kumweng said:

I leave my car at car park for a week unused. last night I try to start me car. I crank many times and then finally started. The battery was strong. After start, the car vibrate a bit while. The RPM needle move up and down and dieing off again. AFter warm up, car back to normal.

What happen? ANy advise

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How do you know your battery was strong? You measure the voltage before starting the car?

Not sure how old is your car. Older cars sometimes may have parasitic current leakage draining the batteries slowly even when everything seems switch off. 

[Wormee]

From TS description, my guess is weak battery. Like bro @Starry said, how do TS know his battery is strong. Having a proper tool to measure both voltage and CCA (Cold Cranking Amp) will tell your battery’s health. 

TS mentioned started after a few tries, rpm goes up and down and died is quite common sign for a weak battery. After warming up car back to normal. I hope TS runs the RPM above 2k (typically for the alternator to charge up the battery) for about 10mins or so. Driving it around also does the same thing. 

But if one starts the car, let it run at idle for 10 mins and switches it off, that is not warming up hor. You will kill your battery faster. Idling the rpm alone does not help, alternator does not produce electricity to charge up the battery. In such cases, the car will have difficulty or cannot even start the next time. 

Of cos, there are other uncertainties TS did not mentioned. How old is the battery? How old is the car? Carburettor (maybe really fuel choked) or injector? Any car camera recording 24/7? 

[Beregond]

  On 9/25/2021 at 4:23 AM, Wormee said:

From TS description, my guess is weak battery. Like bro @Starry said, how do TS know his battery is strong. Having a proper tool to measure both voltage and CCA (Cold Cranking Amp) will tell your battery’s health. 

 

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actually u start the car u will know if battery strong or weak, if u know how to differentiate.

if the battery is strong, it can do many crank. mean the piston go through 1 cycle ( dun know how to say ) and if there is fuel and air. the engine will come alive.

if battery is weak, the car will struggle to do 1 crank, the symptom is hard to miss. and if the battery weak until cannot start, high chance u will hear many tac tac tac tac sound. 

[Ody_2004]

Idle air valve problem?

 

[Arogab]

  On 9/25/2021 at 3:52 AM, Starry said:

How do you know your battery was strong? You measure the voltage before starting the car?

Not sure how old is your car. Older cars sometimes may have parasitic current leakage draining the batteries slowly even when everything seems switch off. 

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He can crank many times means his battery is strong. Haha, no need to measure. I suppose should be other issues

[Arogab]

  On 9/25/2021 at 4:23 AM, Wormee said:

From TS description, my guess is weak battery. Like bro @Starry said, how do TS know his battery is strong. Having a proper tool to measure both voltage and CCA (Cold Cranking Amp) will tell your battery’s health. 

TS mentioned started after a few tries, rpm goes up and down and died is quite common sign for a weak battery. After warming up car back to normal. I hope TS runs the RPM above 2k (typically for the alternator to charge up the battery) for about 10mins or so. Driving it around also does the same thing. 

But if one starts the car, let it run at idle for 10 mins and switches it off, that is not warming up hor. You will kill your battery faster. Idling the rpm alone does not help, alternator does not produce electricity to charge up the battery. In such cases, the car will have difficulty or cannot even start the next time. 

Of cos, there are other uncertainties TS did not mentioned. How old is the battery? How old is the car? Carburettor (maybe really fuel choked) or injector? Any car camera recording 24/7? 

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Bro, I think unlikely leh

[Soya]

Lol....everyone tikam mechanic coz TS neber say what car, how old, etc

I oso say: "It's normal"

Learn from AD workshop mechanics one (when car under warranty)......

After warranty, super expert diagnosis come out. Everything oso must change 

 

Edited September 25, 2021 by Soya

[Nolicense]

  On 9/25/2021 at 5:06 AM, Arogab said:

He can crank many times means his battery is strong. Haha, no need to measure. I suppose should be other issues

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i suppose it may be a sensor issue. rpm hunting is engine management by computer swinging between what it thinks is rich or lean air fuel mixture, which due to faulty sensor/s, keeps giving funny readings.

after warm up is steady, could indicate a warmed up sensor operating optimally again? 

too many design and sensor pattern, but most of the time it is O2 sensor or mass flow sensor. 

im leaning that way. possible?

[mersaylee]

  On 9/25/2021 at 5:40 AM, Soya said:

Lol....everyone tikam mechanic coz TS neber say what car, how old, etc

I oso say: "It's normal"

Learn from AD workshop mechanics one (when car under warranty)......

After warranty, super expert diagnosis come out. Everything oso must change 

 

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Newton law it's liddat one only apply during warranty...after that, LTA law must change this and that otherwise cannot pass inspection 😁

[Nolicense]

  On 9/25/2021 at 3:20 AM, Beregond said:

If old car liao and u drive once a week only.  Dun need spend  so much money on it liao.

U mention after a while the car back to normal. So I guess  it will be extremely  hard for mechanic  to pinpoint the issue also.

Mostly  its try and error which mean putting your money at risk. 

High chance its fuel system or air intake.

Are u ok with stuff like changing the fuel pump try and see how first? 

 

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if fuel pump issue like not enough pressure, then probably car start then die when pressure drop off. but after warm up it idle normally. so fuel pump still can tahan.. not sure if he rev a bit or drive a bit.. 

i kenna con change fuel pump many times... when it is not fuel pump.. lol

[Beregond]

  On 9/25/2021 at 5:50 AM, Nolicense said:

if fuel pump issue like not enough pressure, then probably car start then die when pressure drop off. but after warm up it idle normally. so fuel pump still can tahan.. not sure if he rev a bit or drive a bit.. 

i kenna con change fuel pump many times... when it is not fuel pump.. lol

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 if park short period  no issue starting but park very long , can crank but hard to start  very high chance is fuel issue or air intake issue 

can crank but cannot/hard to  start can be  many thing. the cam and crank sensor is another popular fault esp for korean cars.

then the key immobiliser also another common fault. some ppl drop their key or remote. if the chip damage, u can crank until u die, the car wont start.