Bought an RVR about three months ago with rough running and idle issues, did the ecu fix (thanks to this forum) and traced the rough running to cylinder three and a slightly weak running cylinder four, checked spark, plugs, electrical feed to injectors, evenutally removed commom rail and injectors, full of a dark brown sludge. Started running rough yesterday, exactly the same sludge in the injectors.

Run injector cleaner through last time, before I start the long trek from injectors back to tank, anyone else had this problem or know how to sort it?.

Cheers

Dave

I have a similiar problem so I'm interested in any replies you may get. I did find my dist cap and rotor quite worn so I need to change these soon and also do the fuel filter which I presume you have done already??

Jim

PS: Can you elaborate on the ECU fix or at least point me to the thread you used?

Fuel filter on the list for this week's jobs to see how it goes, apart from this the car has been fine.

Cant find the post for the idle fix, however the jist of it was that Rubycon Electrolytic capacitors in the ecu leak, the electrolyte damages the ecu and reduces the capacitors efficiency. There are three of them at different ratings (can't remember what) however unsoldering them and replacing them cost me about 58p for parts, cured it instantly. The funny thing is that it doesn't show up on a diagnostic check as it is an internal part of the ecu not a sensor pulse.

Wouldn't recommend doing it if you are not confident or dont have a spare ecu!!

Dave

Thanks for the reply. I feel confident to do this work as I am an elecctrical/engineering technician. Don't have a spare ECU though so will have to make sure it works. Most devices like this I've seen are impregnated with epoxy which it makes it impossible to repair.

Apart from rough idle did you get poor acceleration with the fix?

Jim

Jim

Idle issue fixed with the ecu, cleaned the ecu first with carb cleaner then a toothbrush and bicarb removed most of the electrolyte, soldering straightforward from then on in.

Removing and cleaning the injectors fixed the poor power/acceleration issue, however if you haven't already removed the injectors (2 bolts) watch out for the injector seals they perish. I packed them with PTFE tape and refitted them.

Dave

found the thread-
http://www.mitsubishi-forums.com/t24483-93...dle-trouble.htm

Dvae,

Thanks for the info and link. I will have a look at the ECU in the spring (winter in NZ now) and do the other jobs that have been stacking up. I wonder if my Pajero has a similiar problem as funny idle problems crop up now and again.

I have found that leaking caps in several PCB's cause all sorts of headaches and have replaced with good results. These caps only last approx 10 years and often fail sooner if temps are elevated. I probably don't have the brand specified in the link but imagine I won't make any diff.

Jim

Replaced the inline fuel filter, it had a fair amount of very fine sediment in it, hopefully should cure the problem. Will keep the post upto date if this is not the case!

Early 90’s Mitsubishi ECUs are notorious for having leaking capacitors. If you do not catch them early enough, your ECU will be RUINED by leaking acid! And poor idle can be one of the symptoms.

Do you guys have an EGR system on your RVRs, or is it only a US market thing? EGR system dumps certain percentage of exhaust gasses back into the intake manifold for the sake of cleaner emissions. Well, it works OK at first, but with time, exhaust gasses coat your throttle body, intake manifold, injectors and intake valves with carbon deposits. And eventually (after 60-80k miles), when carbon deposits build-up, problems arise.

So if you do have an EGR system and are experiencing idle problems, I would look into cleaning your throttle body and intake system.

RVR's in the UK are all Jap import's some come with EGR, but most of the time when they start failing we chuck blanking kits on and dont worry about the gas recirculation again!

Well, that is the problem with EGR system, even when it work as it is supposed to, it is clogging up some critical components in your intake system. So, as far as I am concerned, there is no such thing as a well working EGR system.

We also blank them out ;). The problem arises with the OBD2 cars, which trigger a “Check Engine” (and a code) when you do that. And then, you can’t your car inspected (MOT for you?).