Evo vii misfire/cut out

[Squiddy]

Hi guys,

got my VII registered this morning no dramas

On the way home on the freeway as Im coasting at 100 in 5th gear the car starts to intermittently cut out (not stalling, but just briefly losing power). It has been getting worse and worse during this afternoon, to the point where now it is struggling to idle smoothly. The intermittent cut out seemed to occur only between 2000-4000 rpm to begin with, although now it is doing it right through the rev range.

Took it to Techsport and Jeff changed the plugs, coil packs and leads to no avail. Im going back on tuesday when he has a hoist free to see what the problem is.

Anyone have any suggestions in the meantime? A good mate of mine suggested the CAS may be playing up. I am worried that I may have got some of the dodgy fuel today. but I filled up with BP ultimate on dandenong rd so Im not sure that is the issue, Ive checked the plugs and exhaust, which are both clean/normal .....

thanks in advance

 

[Entaran]

At cruise even dodgy fuel won't make a lick of difference because you're nowhere near high boost.

My suggestions would be a fuel pump on the fritz possibly (not supplying enough pressure or intermittent pressure), a blocked hose somewhere in the fuel system.... is your alternator working? Put a multimeter across it. It doesn't sound like a CAS problem but I guess it's possible.

Jeff will sort it

 

[BMGTZ]

fuel filter clogged.....had a similar issue to this, that was the solution in my case

 

[Squiddy]

Guys,

Went to chadstone mitsu bought and installed brand new CAS. Problem still happening.......

Any ideas???

 

[Jonson]

Why would you buy a brand new CAS with out having the old one diagnosed? It doesn't sound remotely CAS related. I would definitely say fuel related, as above, check your filter and your pump. This board/forum is full of knowledge, when your asking a question, it helps to listen to peoples answers.

 

[Entaran]

Also, jonson is a mechanic and will know more than most of us.

 

[Squiddy]

OK

after a bit more research and banging my head against a wall I came across a thread on Evo OZ about people having similar problems.

After we eliminated the CAS (almost everyone who heard this problem at Mitsubishi, service and Trade and Evo OZ said CAS in response to your query......) the other possibilities were fuel pump and AFM.

Quick trip to Autobarn, we got some AFM cleaner. Pulled out the airbox, sprayed it all thoroughly, let it dry, refitted - drove home without hitting boost.

It didnt happen on the way home at all :thumbsup: so I took it out for a blat and a wash. No issues with idle, or going on/coming off boost now.

It does feel a little less responsive, so I will take it to Jeff to get looked at on tuesday regardless.

Problem appears to be fixed for now

 

[Liberoz]

I found when swapping to new intake that mine was filthy gave it a clean as above and it drove tons better damm oiled pod filters