Lumpy Idle, TH 3.5

Hi,

My magna has a very lumpy irregular idle. Ive just had the 3 rear spark plugs changed, and the throttle body cleaned out since it was filthy. It still is a very lumpy idle, sometimes it gets so annoying that I shift to neutral at the lights or whatever.

Mitsubishi told me today also that the leads in the car are after market and that the idle will improve if i give it a bit of a go on the highway..Does that sound right??

Does anyone know where I can look to make the idle smoother??

TIA


Chris

[gauss07]

does your rpm needle move erratically when the problem occurs? i'm experiencing abit of what you have now. i don't know the extent of yours but when i'm at the red lights with gear in D, brakes on, there is substantial vibration. sometimes it's so bad you could see the passenger headrest vibrating quite hard. my mechanic told me it could be worn leads. but yea, i shift it into N if it vibrates too much and it stops. don't know what's the true reason and don't know if my case relates to yours but i might get my leads changed next year. let me know how yours go...

oh yes btw, screw what mitsu said cos my leads are mitsu originals and i still have that rough idle. but i'm thinking of changing to bosch ones next time round.

[Killbilly]

Engine mount? Dont worry about Mitsu originals..Mitsu will do anything to get you to buy genuine so they can have your first born child because the parts are too expensive

[gauss07]

got me engine mounts replaced under warranty last year. unless those mitsu bastards didn't actually change them...

[..GONE..]

Check your injectors too.. Had that problem with the 3L TF, chucked some of that injector cleaning stuff in with the fuel and all went well. Thats as far as my knowledge extends.

SuFz

[Killbilly]

Could be injectors? Possibly your O2 sensor, they affect idle and cruising so there's another possibilitly.

Well I had the throttle body cleaned before I had the sparks done adn the idle was so smooth..A week later it was idling again. Like I mentioned before, the idle has improved slightly since I got new sparks done. Ive heard of injector cleaner and stuff but is that good for ur car? I remeber watching like 60mins and they reckon that it did jack all for ur car and was soem big conspiracy by the oil companies or some crap. Dunno thats what I heard. Im gonna get the car checked out again next week so ill let ya know

Chris

[Killbilly]

Injector cleaners works better as a preventative measure and not a solution to an existing problem.

Best off to get them ultrasonically cleaned and then run an injector cleaner every 15,000kms or so just to keep it clean and get better longevity out of them.

[..GONE..]

WTF?!

Longevity?!

Riite.. Ahh well.. It fixed my problem, took me approx. 450/500ks to do so, but yeah.. it fixed the problem. If you don't like the sound of the injector cleaner in the fuel tank, then go to your local mitsu dealer and tell them you want your injectors cleaned. They do it for free for us every 2 services, long time customers.. deserve good service.
Fulla's working in the paint department of hardware stores dont.. j/k KB!

SuFz

[Killbilly]

Do you want a dictionary?

5 entries found for longevity.
lon·gev·i·ty P Pronunciation Key (ln-jv-t, lôn-)
n. pl. lon·gev·i·ties
Long life; great duration of life: His longevity vexed his heirs.
Length or duration of life: comparing the longevities of the two peoples.
Long duration or continuance, as in an occupation: had unusual longevity in the company; her longevity as a star.

I hate being right.