rough running legnum

[xjapan]

hi all, Ive been having issues with my legnum running rough /misfiring.

I have changed plugs and put new leads, the misfire has gone but it still running rough at idle.

I have looked for air leaks, no leaks found.
I don't have a engine light on.
Also it just doesn't seem to have power although is seem to rev ok.
Its only been on the road for a week after being imported and complied.

It was running a little rough when i got it, but it has become worse as it was driven. Thats why I changed plugs and leads.

Any ideas??


Thanks

 

[TomTom]

Could be a faulty air flow meter... have you got a stock airbox etc?

 

[xjapan]

yep stock Air box. no mods at all

 

[towny36]

My car had a similar issue turned out to be a blocked fuel filter

 

[jungle]

Is it rough only at idle? Give us some more info to help diagnose the problem- the more the better!

 

[timmae2006]

did you service your coilpacks?

 

[Guest]

mine is rough on idle since i got it, it idles at about 600 revs but it still its been ok on the pick up and average on fuel. i had it at mitsi and they never found any problems.

 

[xjapan]

Hi all

Its rough only at idle, it doesn't have a misfire
service coil pack? all i did was to make sure they are sparking and cleaned them

Haven't changed fuel filter, but i would have thought if it was a fuel filer it would become worse at higher rpm. correct me if i'm wrong

today i reset the ecu, didn't fix the problem
cheers

 

[xjapan]

any idea's ?? i have researched nothing i have done seems to fix the problem.


I'm worried that I might damage the engine by driving it, as i have no other car to get aroung in (my wife that is )

 

[mchieff]

Idle speed should be 650 IIRC. Wind it up and see how it goes, mines a touch lumpy and its right on 650, i'd imagine it would be get rougher the lower you went

 

[fieldy107]

Idle control valve or MAF sensor maybe? You tried sticking a paper clip in and pulling error codes?

 

[xjapan]

no haven't tried the paper clip, i didn't think i had to as i have no check engine light on? am i wrong?

also tried to increase the idle a little, but it had no effect on the roughness of the engine

 

[Hotwire]

Hi all

Its rough only at idle, it doesn't have a misfire
service coil pack? all i did was to make sure they are sparking and cleaned them

Haven't changed fuel filter, but i would have thought if it was a fuel filer it would become worse at higher rpm. correct me if i'm wrong

today i reset the ecu, didn't fix the problem
cheers

In relation to the bold, how did you make sure they are sparking? hope you didnt just earth out the coilpack like the old days of holding a lead to the block... modern electronics dont like that much.
Other than that, did you use contact cleaner and NOT silicone spray like some suggest? Silicon spray will add a barrier making spark worse, not better.

and with regards to codes, NO you wont necessarily see a CEL before actually obtaining a code - run the paperclip trick.

 

[Guest]

i increased the revs aswell didnt help and i have had the car a couple of years mate and it hasnt broken anything in that time

 

[Guest]

Does it get worse with the air-con on? How about when you quickly let off the throttle when driving, eg: slowing down for a turn.. does the engine almost cut out?

Also, in order to properly adjust the idle RPM you need to disable the ISC servo during the adjustment process. I use EvoScan, I'm not sure if you can simply unplug it.

 

[AKKO]

MAF sensor maybe?

Has anyone had any experience with the CRC MAF sensor cleaning spray, any good?

did you use contact cleaner and NOT silicone spray like some suggest?

Has anyone used CRC automotive electronic cleaner for this purpose with success?

 

[Guest]

http://www.benzworld.org/forums/gen...lectrical-contact-cleaner-vs-maf-cleaner.html

 

[xjapan]

ok guys/gals still having problems. At idle still very lumpy, tried to see if the ecu was giving out any code. no luck there.
i'm getting around 380kms out of a full take mostly stop start driving. (i'm guessing this isnt normal)
I was wondering if anybody from melb would like to help me out by lending me there airflow meter, i know its a big ask.
i can meet them somewhere and swap it over there and then just so i can elimate the afm. you can also give your view on the running of the engine as you will see it first hand.

I'm in the northern surburbs but willing to travel. pm me if your willing to help me out. Thanks again

 

[naughtika]

380kms is pretty good for a stop-start driving..

..but still lumpy idle isn't good.. have you posted up a video of it?