My car won't start when it's warm

[samurai]

Hi all

I have a 1999 4G93 Legnum. it has a weird problem lately...It can not start when it's warm..

I can start the car in the morning..but after drive or when engine warms up turn it off i can't start back on..i have to leave the car to cool enough then I can start it back on.


prior to this problem, worked on:
Coolant
Crank sprocket and crank sensing blade
jump start coz battery went flat - fully chaged with househome plug in charger
ATF

So far I have replaced n checked for:
4 Ignition coils - improve abit of power and stutter
Check for sparks and that was okey
Fuel pump was reading abnormal so replaced
starter n Altinater seems working fine according to mechanic

My Mechanic used OBII? to diagnose the probs but nothing found so went to mitsi dealer, again no error code detected. possibly battery went flat n reseted ecu.

I cant get codes n it could be anything from main relay, ecu, sensors but i need some advices..thnx

[Exhaust power]

replace your coolant temperature sensor. and to also check crank and cam sensors.

does your car stumble or stutters when you floor it?

[samurai]

Hi Echaust Power

Car did stumble and stutters but when replaced ignition coils went away.
Now my car is in garage for couple weeks...mechanic have no idea whats wrong...I think just sitting there.

I might pop in and clean some grounds and check all connection for corrosion...
I might also drive around for while n see OBDII can detect some codes...

Keep you posted....

But If anyone has further suggestions much appreciated

[allrice4g64]

you would think if it was the crank sensor it would throw the code imedietly. iv heard a couple issues about this in the 2g dsm world over on dsmtunners and they pin pointed a couple from ecus getting to hot because of leaky capacitors. maybe take the ecu and look for that otherwise coolant temp sensor,fpr,crank sensor

[harper57]

Solenoid in the starter may be bad

[samurai]

Thanx allrice4g64 and harper 57

Prior to visits to my garage I call them n he replied ...now they cannot start even jump start.
Sounds like starter is going bad like harper57 says....but do you guys think hard to start up when warm is related to bad starter??

[Exhaust power]

His symptoms are car starts when its cold but doesnt want to start when its hot.

perfect example of a bad coolant temperature sensor.

[samurai]

by the way my battery is relatively new only 2 years old with 3 year warrenty..now normal reading should be above 12v? or should it be better?...I heat new battery is about 14v. Reason I ask is I read this guy owns nissan maxima n had problem with starting and when he jump started his car, didnt work. His battery read around 12.85v but he replaced to new one, as reads 14v. When he placed new battery it starts perfectly without probs. He also took his starter but couldnt find any problem but under warrenty so replaced. So seems like his old battery reads above 12v or normal battery cant operate starter..is it mean I need to get one two??

[samurai]

thanks for prompt reply..u do reply super fast

How often need to replace sensors??? every 100,000kms?
Do yo know roughly how much coolant temp sensors is??

[Exhaust power]

check in with your local auto parts store like auto zone or advanced auto. They run about $25-30 dollars in the us not expensive at all.

[samurai]

Thank you for that...I just called Mitsi dealer it was $110+gst in New Zealand.

According to Japanese Galant and Lengum Forums...they said best change every 100,000kms just for safe side coz once sensors goes too much trouble finding the problems

[Exhaust power]

your welcome

[samurai]

Talked to mechanic n said Starter is good as it cranks and battery is read 13.5v but still not jump start...what does it mean???..if u have bad starter dont crank??...

[samurai]

now seems like coolant temp sensor is still culprit but car wont even start cold..ouch..now what?? crank position sensor..could be....mechnic saids 90% is GDI high pressure fuel pump... what do you think??

[samurai]

but does it explain all the symptoms occur resembles GDI high pressure fuel pump failure???...why does ecu not picked up the code??...is it because battery is taken out caused reset of ecu?...oh boy I got a headache..any one??

[varroa]

it could be that, for sure.

when was the last time you cleaned out the pump/replaced the filters inside it? from what i remember, the clearances in that thing are super tight, and bad gas will kill it. so i would say, take it apart and check every dimension you can, also check the filters/replace them as necessary.

did the car throw any codes before it died? does it have any codes now?

you mentioned that "the fuel pump was reading abnormal, so i replaced it". were you talking about the high-pressure pump?

[samurai]

Hi Varroa

I never knew a filter is inside GDI high pressure fuel pump. Say part from filter is there are any other part of GDI high pressure fuel pump go wrong?? It is hard to do take a part by amatures to do?

I was referring to fuel pump in behind driver seat. sorry about the confusion.

I might ask to check again tomorrow for codes.

[samurai]

Do anyone has a schematics or detail picks of GDI high pressure fuel pump??

[Corey2kG]

I had the same issue with my civic about 4 years ago. My starter was going bad. It would start up when its cold no problem and when it was warm it wouldn't start. i would give the starter a couple taps with a hammer and it would start. Eventually i got a new starter and the problem went away. Check that, take it out and get it tested. And recently my G was having issues like it wanted to turn off and it turned on the check engine light. I scanned it at school and it was a random misfire. Turned out to be bad gas. i ran it until it was empty and filled it back up and it went away. So again I would check the starter.

[samurai]

Hi Corey2000Galant

Thank you for ur advice...when your starter was going bad..did still crank? or just click?...so would you say that my starter is bad enough for jump start but not bad enough from stop cranking??..do you think another reason not take jump start is because over cranking and flooded the spark plugs??? flooded with oil or fuel can still spark?

[samurai]

I also read jump starting the empty battery (say result of leaving lights on) that is stress on altinator and can damage the altinator from over heating....and wont charge the battery even drive for 1/2hr.....come to think of it...I have drove for least 45 min but didnt charge...so end up charging using plug-ins....battery is working fine...but more i think about it, i feel uneasy about it...anyways that I can test alternator without removing them?? a part from removing -ve wire of battery (this is appearantly big no no for modern cars) any one??

[Corey2kG]

Hi Corey2000Galant

Thank you for ur advice...when your starter was going bad..did still crank? or just click?...so would you say that my starter is bad enough for jump start but not bad enough from stop cranking??..do you think another reason not take jump start is because over cranking and flooded the spark plugs??? flooded with oil or fuel can still spark?

It just clicked when it was warm. If you crank it too much you can flood it and it would have to sit for a bit. just try that and see how it works..

[samurai]

My starter did cranks strong when its warm....mechnic might of over cranked it...I might check spark plug for flooding first before replacing starter....do you have any thoughts about coolant temp sensors??

[Corey2kG]

Honestly I would just change them its an inexpensive part.

[samurai]

Starter is changed but same condition...cranks but wont start...any other possibility?

now, car wont even start at all even jump start....no codes since cant start at all.

[samurai]

Should I change GDI high pressure fuel pump??

[Exhaust power]

have some one turn your key to the on position. while there doing that put your ear on the middle of the back seat you should hear fuel pump turn on.

why didnt you get your old starter checked out? can you go to a junk yard?

[samurai]

I have already replaced fuel pump because reads lil low from normal.

[Exhaust power]

did it fix your problem?

[harper57]

Yeah it is definitely the starter yall are thinking way too hard on this LOL

[varroa]

have some one turn your key to the on position. while there doing that put your ear on the middle of the back seat you should hear fuel pump turn on.

samurai was asking about GDI high-pressure fuel pump. it's somewhere in the engine bay.

samurai: try to do some diagnostics first, a GDI fuel pump ain't that cheap.

[samurai]

Hi Guys

Thank you for ur inputs.

Yes, I have replaced the starter Corey2000Galant suggested earlier, later supported by Harper57. But main difference between his problem and mine was my starter still crank even when engine is still warm and cold. His one just clicking thats all. If mine just click then I would immediately think starter....despite this I have changed it but still problem exists.

An intial question was car wont start when its warm..but car wont even start at all now.
Battery is good keeping charge of 13.5v(too much cranking cause loss of juice though). Change fuel pump on under backseat. The fuses are all fine. Spark plags are good, Ignition coils are replaced. grounds are good.

Remain no code since last diagnostic...n done three times (once by mitsi dealer service centre and twice by OBDII). possible cause of no code are from unplaged battery (reset of ECU)

So next step is planning to get second hand GDI pump around $300 with 3month warrenty with new filter. Reason behind this is I have called up mitsi dealer n they said 90% of the time is GDI high pressure fuel pump....But I am still not convinced since no codes are shown. though worth a try.

others suggests, crankshaft position sensors, since lack of acceralation and stutter occured before changed igition coils....igition coils made better but I might of cover up the deep root of sensor problem????

Any more advice??

[samurai]

I will going to replace Cam/crankshaft position sensor.

Accroding to Japanese forums....when car has problem starting is likelihood that problem with cam/crankshaft position sensors under symptoms like hard to start when engine is warm, stall, cranks but wont turn over, when driving it stutter, lack of accelaration, has popping, back fire or miss fire. Typical symptoms that are known to us is engine might stall when driving but this may not be the case. Mitsubishi GDI engine is works propare when both sensors are working as norm, so if either sensor going bad or slowly failing, one sensor may componsate for the other sensors signal so it may not work proapre in one minute but works fine the next...like what I have experienced. When one sensor is failing...fail safe mode kicks in so may cause lack of acceleration or misfire but no engine lights so on...but engine and performance may good as usual next minute. So best to diagnose first before unplugging the battery because it will reset n lose error codes like I have.

Lifespan of sensors can be differ and modern sensor can last for yonks...but recommendations by Japanese Mitsi service staff is change every 100,000kms same as cambelts.

After writing all this...I could be wrong because I am writing this before replacing my sensors...I will keep you posted.

Now, another tip by Japanese mitsi forum for GDI engine is...even with Japanese fuels, GDI engine has problem of carbon buildup...make sure carbon cleaner is use regularly and GDI high pressure fuel pump filter is kept clean. should use subaru upper head cleaner or seafoam before oil change would be good idea...and GDI high pressure fuel pump filter is replace every now n then...say 30,000km....filter is only cost $8-$10...labour...I dont know..an hrs work??

[starh4x]

GDI = garunteed dealer income. fix it . sell it. dont make the mistake of buying another.

[samurai]

Yeah starh4X your totally right...Unfortunately...Mitsubishi dealer only sell New Zealand spec sohc engines Galants but not GDI Galant. There are too many GDI Legnums in NZ now n second hand Dealers nor mitsubishi dealer never explain GDI are not design for NZ fuels. Second hand Galants n Legnums r so cheap in Japan...like ppl pretty much give away those old car since u need to pay abt $300US to get rid of cars...Im sure most expensive Galant or Legnums would be US$1000-$2500 (1999-2001 models) with good specs...N sell for quick cash.

I will fix them n sell it soon as I can

[samurai]

verdict is....not a GDI fuel pump it was camshaft and crankposition sensors

what I learnt from this:

1. Jump start wont fry ECU

2. Dont be fooled by what dealer (I am refering to mitsubishi dealer that not in Japan) saids...what dealer said in this case was... 90% of fault could occur on GDI high pressure fuel pump...guess what they were wrong. if no error code on GDI fuel pump and
if they suggest abnormal readings on GDI pump...instead of replacing whole GDI fuel pump try just replace GDI high pressure fuel pump filter....cost of filter is a $8-$10 (+labour $150 ish) oppose to whole GDI pump $1500 (+labour $500).

3. Make sure to check both cam and crank position sensors. Because if one sensor is failing or faulty another sensor would compensate from total shut down of engine while driving. Instead will show signs as I have mentioned in this threads. So if engine is not running proparely then either sensor is failing or faulty... just to be safe should chnage both sensors. modern car has realiable sensors but there are odd ones.

Finally, my car is fixed but it has the expensive exercise. Anyhow its fix but I am diffinately selling this car to avoid becoming GDI fuel pump statistics.

Thanks to those you gave me a helpful fips and advice..much appreciated