Hard Start after stalling

[danryan75]

Hard Start after stalling FIXED

Hey fellas wasnt too sure where to put this so it ended up in general. I bought my d40 about 1 month ago and has been mostly trouble free. A small problem I have noticed is that when I stall it (not regularly but still getting used to new clutch after the old patrol clutch) it is quite hard to restart. Car kicks over fine and revs to about 800rpm but then dies in the arse all in about 3 seconds. could continue to do this til the cows come home. The only way I am able to get it to stay running is to give it a bit of a rev while kicking it over. it seems to cough an fart its way to 3000 rpm and then revs out freely. This only works sometimes. It then runs fine. Any ideas on what this could be? car was dealer purchased so has 3 month stat warranty so getting it sorted by then would be great. Another thing i have noticed is that the clutch grab point it very far out as in right at the top of the peddle. Is this normal or could it be related? ie clutch still being engaged or something? any help would be appreciated. still getting used to these fancy new cars after upgrading from an old gq patrol.

some background info on car : 2007 d40 stx 4x4 Manual diesel. stock as a rock 70000kms

Cheers

 

[Old.Tony]

Get some electrical contact cleaner, gently remove the MAFS and give it a spray. Don't drop it, don't hit it, don't bend it, heat it or even offer it verbal abuse. It costs about $400 if it needs replacement.

No guarantee that'll fix it - but my research into the stalling problem leads me to believe that is the cause.

The MAFS (Mass Air Flow Sensor) is sitting inside the air pipe that comes out of your air filter box, just a couple of centimetres from the air filter box. It measures air flow. Combined with the air temperature (which it also measures) and boost pressure, the ECU knows how much fuel to squirt in for optimum combustion. An error in any of those sensors will cause the ECU to make a mistake.

I don't have a manual so I can't offer help on the clutch pedal position - it's a hydraulic clutch, so it ought to stay the same unless something in the clutch area wears out.

 

[jayk]

i have the same issue dan. i dont know much about mechanical stuff like tony, but my st is a pain to get going again when it stalls too!

 

[mitch92]

Don't stall it? Sorry useless i know, but it's the best i got.

Cleaning the MAFS is pretty simple, can be done yourself and once done you will know if it is something simple, or if it will require more investigation, so not too bad a place to start.

 

[danryan75]

Don't stall it? Sorry useless i know, but it's the best i got.

Cleaning the MAFS is pretty simple, can be done yourself and once done you will know if it is something simple, or if it will require more investigation, so not too bad a place to start.

Thats always the goal but Unfortunately I sometimes stuff up. Generally it happens on a steep incline or the like. It seems to shudder when taking off sometimes too. could this be related to mafs? ie not right ratios making it run lean?

cheers

 

[Old.Tony]

Diesels run lean anyway. There's no regulation of airflow into the engine, like in a petrol - power is controlled purely by the amount of fuel injected.

But, to answer the question, yes it could be the MAFS. It could also be the suction control valve on the fuel pump, or an error in the fuel rail pressure sensor (have heard of these failing a little). Any of these should throw an error code and may even bring on the Check Engine Light on your dash. Has that happened?

 

[danryan75]

Diesels run lean anyway. There's no regulation of airflow into the engine, like in a petrol - power is controlled purely by the amount of fuel injected.

But, to answer the question, yes it could be the MAFS. It could also be the suction control valve on the fuel pump, or an error in the fuel rail pressure sensor (have heard of these failing a little). Any of these should throw an error code and may even bring on the Check Engine Light on your dash. Has that happened?

Appreciate the help Tony. No check engine light on dash and Im unsure of how to see error codes but havent seen anything obvious.

cheers

 

[Old.Tony]

There probably won't be an error code unless there's a CEL on. Error codes can be read by a CONSULT device (Nissan techs only), or a Scangauge ($200, www.scangauge.com) or through neat software on an Android smartphone like Ian Hawkins' Torque and an ELM327-compliant bluetooth OBD adapter ($55 for the adapter, $5 for the software).

 

[mitch92]

I do know what you mean though. One of our fire vehicles is a 4.2 patrol. Couple days ago i did over 250km driving it, at what was probably average speed of maybe 15-20km/h, lots of low-range stuff. Every time i jump back into the Nav it takes a little to get used to the clutch again.

 

[04SilverSTR]

Next time you stall try turning the key all the way off then restart it. This resets the computer. My inlaws common rail patrol is a pig to restart after a stall and he has to do this and i goes first time.

Bryan

 

[Tills]

I have heard that the nats system can cause grief after a stall. So turn it off fully even removing the key lock it and start again might help. A local bloke got his stuck on the boat ramp after a stall couldnt start it after a couple of hours with roadside assist they tried the above and away it went.
cheers

Tills

 

[ONLOCK]

iv only had the problem once where mine was hard to start after stalling but given your info regarding the car being a 2007 model the injectors are a problem in that model so it could be one or more of them, maf sensor could also do it, if its under warranty still id take it back. as for the clutch, after 70,000kms it could be slowly on its way out, some people get less kms than that, i doubt nissan will waranty it as they will just say its general wear and tear. take it to your local 4x4 diesel mechanic to have a look at it and give you a prognosis (spelling)
goodluck
kyle

 

[user 1279]

Mine is a 2010 model ST and mine does the same thing quite regularly (it's not only if it has been stalled but that's when I've first noticed it).

Revs to about 800rpm and then stalls. This can happen about 10 or 15 times in a row. Sometimes if I leave it for a minute or so it corrects itself.

I've reported it at the last three services and each time they report that they cannot find any issues.

Interesting to see it is happening to other owners.

 

[ONLOCK]

actually, chuubs on here had a similar issue, ran some diesel injector cleaner through it and it seems to of cleared up a bit, maybe try that, at least its not expensive

 

[jjohn]

Next time you stall try turning the key all the way off then restart it. This resets the computer. My inlaws common rail patrol is a pig to restart after a stall and he has to do this and i goes first time.

Bryan

Yeh I had a similar experience.
I turned the ign off but not all the way and then tried to start it again.
It ran for a few seconds and stopped. I started it again and the same thing happened. I turned it all the way off and tried again and it went fine.

 

[danryan75]

Gday fellas, if anybody is still interested, I managed to trace this fault back to an undervoltage battery. changed battery to a new unit yesterday and tried to replicate the fault and couldnt get it to happen.

Thanks for the advice

 

[jjohn]

Gday fellas, if anybody is still interested, I managed to trace this fault back to an undervoltage battery. changed battery to a new unit yesterday and tried to replicate the fault and couldnt get it to happen.

Thanks for the advice

Great that you followed that up for us.
Interesting outcome. It took a while to show itself.
Nissan didn't read a low power battery? Mmmm.
Lucky we have a forum.