Issues with warm starting.

[darklordscotty]

Hello everyone,

My wife and I have just purchased a 2018 Pajero Sport GLS with 8100 on the clock. We picked the car up on Wednesday.

Since picking the car up, I have become very concerned about the length of time it takes to fire the engine up, particularly when the car is already at operating temperature. Basically goes like this:

1. Cold start there are zero problems - fires up almost instantly.
2. Car is driving with no issues at all as far as I can tell. Engine seems nice and responsive.
3. Drive the car around for 30 minutes to an hour and park it somewhere. Walk away for 30 minutes to an hour.
4. Jump back in car - the car is still at operating temperature. Starting the car takes a long time - sometimes 5 seconds, sometimes 10 seconds, sometimes 14 seconds!

Today, things reached a head and the car outright refused to warm start. I actually have this occurrence on video. I was convinced at this stage it was the battery as the starter motor was struggling big time.
I bit the bullet and purchased a new Century 4x4 overland battery. Installed the batter which was already charged, and took it for a 40 minute test drive. When I parked it and left it again for around 40 minutes, it still took at least 4-5 seconds to kick over even with a new battery.

To be honest I am extremely disappointed with the start up performance of this vehicle. I am hoping the experts on this forum might give me some insight as to what the root cause is as I am taking the car back to Mitsubishi on Tuesday and I am dreading the dealership telling me "we cant find anything wrong with it" routine..

This is my wife's car and we are using it to carry around our young baby. It absolutely needs to be a reliable starter - hot or cold starts should not make a difference!

Any information would be helpful - any Diesel mechanics out there that might have some clue? Is it anything to do with the fact that the car sat in the dealership yard for a long time?
Is it normal for the warm start to take longer?!?

Thanks everyone.

[old Jack]

You need to make sure you start the engine without an accelerator input.
Are you doing this?

OJ.

[darklordscotty]

All I am doing is holding down the brake and pressing the start button (eg in accordance with the operators manual).
I am not giving it any gas whatsoever.

Our 2001 NM Pajero V6 would start first time every time...

[BruceandBobbi]

Warranty.

[darklordscotty]

Yeah I know it is a warranty issue, but I am hoping for a concrete explanation because what I don't want to see happen is for this dealership to turn around and go "we cant find anything wrong"... even though there clearly is something wrong with this vehicle and I have video proof of it.

[old Jack]

All I am doing is holding down the brake and pressing the start button (eg in accordance with the operators manual).
I am not giving it any gas whatsoever.

Our 2001 NM Pajero V6 would start first time every time...

Just eliminating the easy things first.

When the the warm/hot engine does eventually start is there white smoke coming from the exhaust?

OJ.

[nj swb]

At a guess, a fuel delivery issue. For reasons unclear, while it's hot, it takes a little while to pressurise the fuel rail.

First guess is that air is entering the suction line while the engine is hot, but if that was the case, it would still take time to suck the fuel back up while the engine is cold.

Do you have an OBD device to monitor engine parameters? If so, you should be able to monitor fuel pressure, and look for any differences between cold start and hot start. If you can identify a difference then the dealer should start looking there.

[darklordscotty]

To be honest I have not really checked for any white smoke I would need my wife to give me a hand so I could inspect while she starts it.

What would white smoke be indicative of and why would it only be during a warm start occurrence?
Sorry for the 100 questions I am not very familiar with diesel engines...

[darklordscotty]

I do have a bluetooth OBD device so I could look at the fuel pressure and see if there is a difference, at least that is something I can look into - thanks for the suggestion!

[old Jack]

My initial thoughts are if you are having a delayed hot start and getting a smokey exhaust then it could be an injector that is not closing completely at shutdown. If this is the cause then it must be fixed ASAP as a leaky injector can can oil dilution.

Second thought was the brake switch out of adjustment or intermitanently faulty, easy to check at the same time as the smokey exhaust. Brake lights should stay ON constantly during the cranking/starting process.

After eliminating these 2 possibilities then there is quite a list of other sensors that could be causing the problem that will need a MUT to diagnose.

OJ.

[spot01]

You say the car sat in the dealership for a long time - how long? Has fresh fuel been added since you got it?


If this is a car where you must press the brake before it will start, make sure you are pushing firmly.



Try to explain to the dealership exactly what they need to do to replicate the issue, or better still try to show them what it does.

[darklordscotty]

My guess is at least 9 months. Its an ex-MMAL vehicle and apparently the dealership could not move it quickly enough due to the colour (deep bronze). I was told that the dealership added fresh fuel but for all I know they just topped up the tank. I would like to run clean fuel through it to see it that helps too.

Thanks everyone for all the suggestions, I will certainly look into the injectors and will let everyone know how I go at the dealership. I am hoping that the battery change might help too.

Scott

[Greg Grey Grumbly]

Scotty, this is not your problem it is the dealership’s problem. Instead of worrying about this, use your warranty and get the dealership to fix it.

My PS starts first time every time, hot or cold, there is something wrong here but they are equipped to fault find and fix.

Greg

[dragonjon]

I AGREE WITH GREY GUMBY
My sport is 4 years old 2105 model 54000 klms and starts 1st go every time
let dealer fix