Cold start stutter petrol

[Castleman]

Hi all,

I have a 2007 3.0l petrol swb, which has started stuttering really badly on the first cold start of the day. After this it's normally fine, but the first one it takes real effort.

I've seen that this problem occurs on the diesels but anyone have any advice/ideas with it being a petrol?

thanks

Mike

[WogsRus]

could be the cold start valve not sure what it is called on a mitsubishi, but it a valve in the intake which allows a small amount of air to bypass the butterfy, working like a choke.

Maybe worth a try

[Castleman]

Thanks for that.

Noticed this morning it's also belching out black smoke when it starts! Argh!

[wrexed03]

4 things to check.
1) ISC (Idle Speed Controler) lives on your throttle body. Remove the plug and the three phillips head screws and give it a clean.

2) In regards to black smoke sounds like its running rich. There is a temp sensor on top of the engine one if for the temp guage (spade Connector) the other is wired into the ecu. The one you want has 2 pins check the connection make sure its plugged in. If the sensor is faulty a replacement is $148.00 from mitsu last time i checked. Try and get one second hand if possible. Bit of a rip for what it is.

3) Oxygen sensor may be wacked but you would notice this with higher fuel consumption this one will need to be checked with a multimeter. If the vehicle has done over 80k just replace it they do get lazy and eventually fail.

4) You may have leaky injectors causing the rich condition on startup. They will need to be removed and flow tested and cleaned if this is the case.

Start with the ISC then the temp sensor and so on.
Hope the above helps.
Ah just remembered. If your vehicle is a dual fuel and you have had a backfire check the honeycomb in the maf sensor. If this has been damaged substantially it will cause a rich condition as well. (Faulty MAF sensor will exhibit similar symptoms as well).



Regards