The Mitsubishi Pajero Owners Club®

Mitsurobbo

Hello POCUK.

I have an issue with my 2.8 pajero Auto with 120k on the clock, which i am looking for advice for. It starts on the button every time i want it to, but when its cold i have a hunting idle, going from say 650 - 800/900 rpm in 'pulses' up and down. In a possibly related issue, when i slow down for a junction say, the idle drops to around 600 ish and doesnt stall but vibrates, but will pick up and settle somewhere near 900 rpm after i have stopped. This happens hot or cold a lot of the time. The idle is never perfectly stable, i am used to diesels idling very steady indeed, but this one even when warm seems to not be 100% but is definitely not as bad as when it is cold. I have no history on when (if ever) the pump seal was replaced or indeed whether this is even a sign of a potential issue on that front. But it has been serviced frequently.

Any ideas what may be causing this?

Thanks.

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Mitsurobbo · Posted: Thu May 04, 2017 12:51 Post subject:

I should also point out i have no real smoke problems on the car that i can discern, blue black white etc...

Mitsurobbo · Posted: Fri May 05, 2017 11:36 Post subject:

Not had much luck yet but i believe i have the later 96' model with the electronic injection pump. I have these 2 vacuum valves in addition to the EGR on the intake that then bolts to the intake manifold.

Id love to insert an image to allow me to show you, but because of a lack of posts i am not allowed to by the forum Rolling Eyes

There is a sensor attached to that housing on the back of it and i have noticed that the housing is leaking a bit of oil where it bolts onto the intake manifold, presumably the sealing gasket has failed and is leaking oil onto the exhaust manifold/turbo which i can smell when the engine works hard.

So, if oil is getting out, air is getting in and possibly cocking around with the idle. Can anyone tell me what this sensor is and if it could be causing my issues?

cheers.

peteinchad · Posted: Fri May 05, 2017 16:15 Post subject:

It doesn't sound like the pump seal.

I wonder if you are getting some air into the fuel system. Try putting a bit of clear fuel pipe between the filter and the pump and look for any air bubbles.

Mitsurobbo · Posted: Fri May 05, 2017 17:28 Post subject:

I'll be whipping the intercooler off and replacing that intake housing gasket over the weekend and i'll try your suggestion. I don't seem to have any power issues and goes well, although owning a 2.5 Paj MK2 auto before the 2.8, i could say that about just about anything.

peteinchad · Posted: Fri May 05, 2017 17:49 Post subject:

Mitsurobbo · Posted: Sun May 07, 2017 11:54 Post subject:

Checked for air bubbles in my makeshift clear diesel hose and i can't see any bubbles when the engine hunts. I cleaned around the intake and repaired the gasket and put it all together. I have noticed there is a possible failed intake manifold gasket on the pot nearest the bulkhead along with the obligatory half moon gasket failure from what i can tell. There is as oil leak both down the back of the engine and from the intake manifold. Been like that for some time by the looks of it. Being the EDC, i reckon it could be sucking in air and taking the mick out of the sensors. I've also treated the car to some v power diesel (So expensive, i wonder if you are buying shares in Shell when you fill with v power?) and some millers magical diesel treatment see if that helps in anyway in case i have a cack spray pattern on one of the injectors. Could it be a dodgy injector?

Failing all that, knowing the car is 20 years old, perhaps its something you live with? It does drive well, no smoke, no power loss, hesitation or hints of impending doom. scratch

peteinchad · Posted: Sun May 07, 2017 13:18 Post subject:

Mitsurobbo · Posted: Sun May 07, 2017 13:39 Post subject:

I'll replace the intake gasket and go from there. Like a modern petrol i suppose, a split hose or a tiny vacuum leak throws it all off. Im pretty handy with spanners but i can't seem to find much in the way of information on these pumps and its electrical side. I have noticed there are 2 haynes books relating to this car, a 1983-96 (NA through NJ) and a 1983-97 (NA through NK). I wonder if the 97' includes a troubleshooting guide for the edc pumps? I know they're haynes manuals but may at least guide me in the right area.

peteinchad · Posted: Sun May 07, 2017 14:04 Post subject:

Trouble with Haynes is that the book will be for the Shogun - and I don't think they fitted the EDC pump to the Shogun, only the Pajero.

Mitsurobbo · Posted: Sun May 07, 2017 16:41 Post subject:

We've just been out on a run today and sometimes it was fine but then it started again. I also have to confess i haven't checked the oil for a while and noticed it was around a third of a centimetre above max. I never did the oil change before due to illness and had a local mechanic do it. It seems unlikely that he overfilled it but i cant say with 100% certainty. If it was the pump seal, would an EDC pump exhibit different signs to a mechanical one? I don't get cut outs or difficult starting, but the oil level has got me concerned.

peteinchad · Posted: Sun May 07, 2017 17:09 Post subject:

Does the oil smell of diesel?

Have a read HERE and HERE and HERE

It seems these people had some symptoms similar to yours with an EDC pump.

You need Mark3 to see this post - he is the expert on this.

If your oil level is increasing and it smells of diesel then be careful about driving it as the engine can run away.

Mitsurobbo · Posted: Sun May 07, 2017 17:45 Post subject:

Cheers pete i'll have a read.

Mitsurobbo · Posted: Sun May 07, 2017 18:28 Post subject:

Indeed the second link "ripface" truck is very similar to mine. Perhaps low down the rev range is a bit sluggish for me, but as i say owning a 2.5 before its hard to compare. When you drop your right foot down though she does pick up her skirt and goes. Perhaps with all the electrical idle control of an EDC pump helps mask some of issues over a mechanical one, as i say it's never cut out but at times it seems like it wants to... What a pile of cack...

Well, from here do think its worth changing the oil, filling it to the correct level to confirm over the next few weeks if it rises? I obviously don't want this to runaway and explode, but what other ways can i confirm with better certainty? Diesel doesn't look dark when i checked for air...

peteinchad · Posted: Sun May 07, 2017 18:59 Post subject:

It maybe worth jut draining a bit of oil out to get it back to the mark on the dipstick and see if the level rises again.

Diesel in the oil will make the oil thinner so that maybe not good for the engine - so an oil change might be worth doing.

Keep a lump of wood wrapped in thick cloth in the truck - and a screwdriver to remove the intercooler pipe and put the wood over the end of the pipe to starve the engine of air if it does run away. Don't try a cloth by itself as it will just get sucked into the engine.

AND - don't use a cloth on your hand as you will hurt your hand.

I have also heard that a CO₂ fire extinguisher stops a runaway engine by emptying it into the intercooler pipe.