Hi All, newbie here.

Recently my 44,000 mile Outlander engine has started juddering at moderate revs on a long run once it has fully warmed up; no engine warning lights come on and the engine temp is normal. The juddering is most noticeable at around 2,000rpm in top gear going up a slight incline. If I drop a gear and take the revs to 2,500 or above, the problem seems to disappear. If I’m stationary the engine will rev perfectly and smoothly from idle to red line, it just seems to be if the engine is under that slight load that the problem occurs. When this first happened a couple of weeks ago I called out the RAC who ran the diagnostics and found no fault whatsoever.

Before I bite the bullet and take it to a garage, with the inevitably expensive diagnostic checks resulting in ‘no fault found’, does anyone have any thoughts or experience on this?

 

What engine is in your vehicle? I'm assuming V6 with automatic transaxle -- a traditional transmission and not a CVT. If you have a CVT, stop reading this right now, because I can't offer any sound advice.

I have no experience like yours, but your description of what's happening sounds to me like a transmission problem rather than one with the engine. The transmission may not be shifting down to a lower gear when it should. Have you changed the transmission fluid lately? If you haven't, there's the first thing I would do if I was in your shoes because this step alone may cure your issue. Eventually you're going to have to do it, so why not now?

 

Thanks for your thoughts, and sorry, I should have been more specific. The car is a 2.2d 4 cyl with a 6 speed manual transmission. Because the car will rev freely when not under load I wouldn't have expected it to be a problem with the turbo and, regarding your suggestion, when it's juddering if I lift off the throttle (i.e. the revs are the same) it stops juddering, which suggested to me it's engine related as if it was anything to do with transmission I wouldn't have expected lifting off to have stopped the juddering

 

In the early 1980s I owned a Mercedes 240D, normally aspirated, with auto trans. Your vehicle has low miles, so it's ulikely that it's an engine problem, unless you haven't been changing oil regularly.

The fact that the problem subsides if you lift up the accelaratior at a given rpm could indicate a fuel-starvation issue. Do you notice any change in exhaust color when the problem happens, and after you lift the accelerator pedal a bit and it subsides?

Is the air fliter clean?

Diesel injectors need fuel that is very clean. Is your fuel filter very clean?

Are you putting the cheapest fuel in your tank? Try putting some quality fuel in the tank with some high-quality injector-cleaner added. See if this has any effect on the problem after about a half-tank has been consumed.

You might want to take a look at the following thread, too, and see if any of it rings a bell.
https://mitsubishiforum.com/forum/mi...s-power-33015/

Good luck.

 

Hi Outlaander, thanks a lot for your thoughts and suggestions. The car is regularly serviced and when the RAC checked it over they confirmed that oil and water were fine. Difficult to check exhaust colour while I'm driving at 60-70mph but I'm not aware of any exhaust clouds, of any colour, when I'm driving whether the car is behaving normally or when this problem is occurring. My main thought is the same as yours, a fuel starvation or injector issue, although I'm not sure why either of those would go away when I revved harder. I am using proper grade fuel so I wouldn't expect that to be the problem but as a try out I have put some Redex Diesel cleaner in recently to see if that makes any difference (none so far, but it's only had one shot). Interesting suggestion about the air filter, which I hadn't considered but, yes, worth checking although, again, if that was the cause wouldn't the problem get worse rather than better if I revved harder? Or as I rev harder does that force more air through and overcome the problem?

Thanks also for that link which sounds like slightly a different problem as mine doesn't lose power or go into limp home mode, and if I change gear it will rev to the red line with full power.

Thank you for your time

 

I’ve got the exact same thing on mine I’ve had egr cleaned and glow plugs done . Likewise I don’t believe it’s the turbo I was thinking a lazy injector also my engine sounds really tappy do t know if it’s linked

 

Hi Neil,

I don't know if you've seen my later thread but, after a lot of research I'm leaning towards the MAF sensor as a possible culprit. I've tried cleaning my current one which made a small improvement but didn't fix the problem. I got an OBD II scanner which also suggested a malfunctioning MAF sensor, plus a bad air/fuel mixture can apparently cause the engine to sound really tappy, which describes mine as well as your car.

I've ordered a new MAF sensor just to see if that's the cause since all garage checks (one by the RAC, two at my local garage and two at the Mitsubishi main agent) have failed to find anything wrong. Once that arrives and I've fitted and tested it I'll post back here to let you know the result.

 

Hi Terry r52
still having the on going juddering , I also went done the maf bought a new one and fitted it made no difference . I done some experimenting whilst driving . The judder seems to disappear whilst using the cruise control system . Had a friend plug his vw scanner in and we found the throttle body was reading 95 % open regardless of driving or idle . I ordered a replacement off eBay £95 it’s 3 t30 bolts the last one also holds the egr value on so I decided to strip that off and clean it aswell did it all fairly easily fitted the replacement throttle body and googled the reset procedure and it’s solved the problem . I stripped the top off the old throttle body and found the main drive cog had half its teeth missing so can only assume my air to fuel mix has been way off resulting in the judder . Might be worth looking into kind regards

 

Hi Neil,

Thanks for all these suggestions - all worth consideration on my part. One difference is though that my juddering/misfire doesn't disappear when using cruise control but I will definitely check out the throttle body opening reading if my OBD scanner shows that. The other thing that continues to puzzle me is that the car runs absolutely fine for up to 10 miles, smooth, quiet (well, for a diesel) and as powerful as you'd expect. It's only after 10 miles or so that the problems start to creep in and I suspect that if there were a problem with the throttle body, like teeth stripped off, I'd have the problem all the time?