Rough Idle After Service

[sarusa]

Checked under bonnet with car at idle after service, engine was , how can I put it! wobbling about more than usual. Took it back to dealers. Mechanic claimed couldn't see anything wrong, it was normal, checked with new car and new car was noticably smoother, he claimed no different. While driving no noticeable difference Decided to leave it at that and maybe get my mechanic to look at it.

Next day started it up looked under bonnet everything smooth and normal, let it warm up, everything normal!
Wandering, as only thing changed was oil and filter, if perhaps sufficient oil pressure didn't get back to something like a valve lifter, or perhaps something else and then corrected itself. Oh1 and air filter checked and put back

Any suggestions?

[lancerdarryl]

Make sure the air filter has been refitted correctly,sometimes the bottom of the air box comes apart if you are not careful.

[merlin]

Possible sticky EGR valve.

[Mooman]

I'm taking a guess here but I suspect at the service they reset the ECU.

The rough idle would then be the car re-learning its' fuel settings, hence why on next start it was ok.

[Dannn]

I'm taking a guess here but I suspect at the service they reset the ECU.

The rough idle would then be the car re-learning its' fuel settings, hence why on next start it was ok.

Why would they reflash the ECU to factory for?

How has it been of late sarusa?

[Stevie]

Was your car/bonnet shaking when idle?

[sarusa]

Thanks to all above for your help. Air filter replaced correctly, sticky EGR sounds a very valid possibility but if so has only ever happened once.
reset ECU was advised nothing other than service items touched, only item reset was date and ks for next service.

All has been fine and now seems fine, thanks Dann. Car is only 1yr and 8months old with just 4,900ks on the clock so still like new.
In fact better than new, run in, now a quiet car to enjoy, due to sound proofing already done, (more to come) and change of horrendous, noisy Yokohama tyres. Can now converse in whispers at highway speeds, with major disruption only occurring, if air con: on auto needs to Catch up quick. Smoother accelerator response and much improved, pleasant sound since installation of RA induction snorkel

Anyone with a NA lancer that hasn't fitted a RA snorkel, do it quick before they become hard to find price new just $175. Magical difference.

[sarusa]

Was your car/bonnet shaking when idle?

No! Just engine noticeable on rocker cover visually.

Have received email and phone call from dealer since complaint asking if any other queries!

[sarusa]

Possible sticky EGR valve.

See your answer as being the most plausible, thanks.

Change of subject. Ive fitted an RA snorkel to my MY15 ES 2ltr CJ. and run on 98ron full time. Is there any point in putting in one of your ECU tunes if in fact you have a set plug in one for for my car at this point. If yes, would it be possible to take it back to factory spec when I drop it in for services. Oh and cost of such a tune and a rectifier if necessary. Went looking for the OBD2 port under the dash and couldn't find it, where is it in a MY15 lancer?

Will one day get around to more free flowing exhaust and will then need a full tune with a thought of gaining mainly as much torque and then some power. As car mainly runs at low revs torque seems the more important.

Things were easy with just carbs and points. On occasions taking advance up to 10% above manufactures specs: for the life of the car, gaining economy and a much sweeter responsive drive. Using my ears to stop, just before the silver paper started crackling. those were the days!!! Turn a screw loosen and re-tighten a bolt and it was done, well almost. Loved playing with SU carbs.

[burfadel]

Service places don't usually go around flashing ECU's unless it was for a specific purpose such as a recall. Not all recalls are shown on the recalls website, only those affecting safety and security. It may be the case Mitsubishi pushed an update to resolve a minor issue, but I doubt it. Therefore, once tuned your car should stay tuned! It's definitely worthwhile doing .

The last thing you want is for an EGR valve to become stuck fully open like happened to me (stuck fullly open due to the high vacuum state of me engine braking down a steep hill). It's not something that was easy for them to find, it took them a week and I got it back just in time to leave right before Christmas. I think they were trying to leave it until after Christmas but I rang them every day, finally the head mechanic took a looked at it and it was fixed within a couple of hours! It's something that doesn't show on computer fault codes, and unfortunately today if there isn't a fault code for it then they can't find it. I can only imagine if it were only sticking partially open they'd probably never find it :S. You might want to mention it to them? Apparently on some Lancers have EGR valves, probably part of the 2013 update on the 4B11? I wouldn't have thought it would happen on a car that is so new though. It probably wouldn't be worth trying something like Nulon Foaming Intake Cleaner.

[sarusa]

Car has always run fine and is still running fine not even a miss and now idles normal just that one glitch.

Jaycar Have a smart meter kit with ten LED's that can be fitted in a car constantly giving you a readout of mixture density and even lets you know when running on a closed loop. Also a buzzer lets you know if a lean-out arises like for eg: a catastrophic high-load "lean out" occurs.

Almost a necessity with turbos:

[Lancer1993]

Would flushing the ECU mess up a Merlin tune?

[Dannn]

Would flushing the ECU mess up a Merlin tune?

It can reset back to factory.

Edit: i cant spell

[sarusa]

Would flushing the ECU mess up a Merlin tune?

lol Flushing it would wreck the ECU but flashing it, would depend what you wanted to do ha ha!

[sarusa]

Would flushing the ECU mess up a Merlin tune?

lol Flushing it would wreck the ECU but flashing it, would depend what you wanted to do ha ha!

My concern is That something didn't happen that shouldn't have happened causing the problem.
eg: Engine started without having replaced the oil as happened at a first service on a Telstar I had. Only 1 year warranty in those days.
Only reason I found out was a year or so later I came across one of the service staff working elsewhere and
looking up at me said. " Oh your the guy whose car they forgot to put the oil back in" Fortunately no damage as car was fine till I traded it in years later.