The Mitsubishi Pajero Owners Club®

[darren smith]

hi all, need help

just purchased a 1996 swb 140 with an electronic fuel pump (poss. first gen ), I need to confirm this as it could be later as some of the documentation is not back from dlva as I could be a late 96 or earlier 97 MY. (may have been first reg in japan late December 1996) many members have had the similar idle issues, poor cold starts, hunting, almost stalling, yet over 1100 revs everything fine. has anyone really got to the bottom of it (without converting to mech pump) and solved the issues?

had previous pajeros with mech pumps which needed pump seals which was the usual cutting out after a couple of mins and then taking time to restart and clear the air- but this seams totally different.

increasing the revs via the choke/throttle helps but as soon as the revs drop, eg pulling up or putting into gear it is a bag of hammers and the idle is really erratic and rough.

I think previous owner knew of issue as I found a note on how to reset ECU

will start to strip everything around throttle body to look for something obvious.- any help will be appreciated.

thanks
Darren

[Google]

[darren smith]

so stripping things back, we have

definite electronic pump, with cable operation and has 2 servos on intake body.

usual leak rear of rocker cover
ECV has been removed and blanked off
intake body has been off before silicone sealer on gasket but leak on bottom gasket with oil blow back getting through, and diy paper gasket put in top seal but to be fair that was holding.
no3 injector had been replaced recently but leaking diesel on centre body connection of injector
no1 injector leaking on pump fuel connector
bleed off return pipe had been replaced just pushed on not sure if it needs proper clamps or clips to stop pulling in air
TPS looks like it may have been adjusted in the past
oil level on low side, but not thin and no smell of diesel

on the throttle body assuming one servo for tick over the other for main throttle opening, when servo fully open on tick over side should the butterfly not fully seal the opening shut?

sorry if I am talking nonsense , will check fuel filter and fuel lines tomorrow

still looking!

[Mark3]

Your symptoms do sound very much like the front pump seal is the cause and they wont be exactly the same when compared to a mechanical pump because this isn't a mechanical pump!


Also air cant be drawn into the bleed off pipe as its not under negative pressure like the fuel feed to the injector pump is.

[darren smith]

thanks for that

since most of the top of engine bits and pieces is stripped away may have a bash doing the seal myself- looks like it the same seal for both.

other question is it worth reinstating the EGR- lots of discussions on does it make a difference

thanks

Darren

[Mark3]

[darren smith]

hi
thanks for that on further investigations I find it is to help also with prompter warm ups and can help emissions, however its gives little or no performance gains and can be more trouble than its worth- so it not going back.

well I am down to the final step of fuel pump removal will need to go through all the methods on the forum to mark up tdc timing marks etc as if the timing is out its a big problem once everything  has gone back together. also found a bad leak on power steering pump with the seals being worn on banjo connection --starting to ask myself why I bought it.

wish me best of British  

[assassin]

The symptoms could also indicate the system is blocked and need cleaning, it is off with the manifold for this.

[Mark3]

[assassin]

Mark, when the EGR and manifold become blocked they throw up some strange and wierd faults and I have seen this several times, not always obvious.

[darren smith]

update

pump removed- yes the hardest part was the 14mm bolt at back on the swing adjustment /mounting just next to starter motor, a 14mm to 1/4 inch socket did the trick to get over the tight clearance, luckily only one to undo the other must have been dropped previously as it was under the pump. it was suggested on a post to give more clearance remove the starter motor electrics, on mine the electrics don't come off the top of starter motor when still attached to engine, not enough clearance.

marked up all settings and got local bosch injection people to change seal- they said seal was not great but not really tough and hard, however it was not a Zexel or bosch. new Zexel seal fitted for £15

banjo bolt a little bit fiddly to get back in where oil line attaches to block, mine snapped even before I started to tighten up when inspected it had been over tightened and stretched previously at oil hole point and you could see the old discoloured breaks on the steel. couldn't find anything quickly so made my own. that's reminds me I have found a few over tightened bolts, people need to be careful when tightening steel bolts into alloy components.

should be back together next week.

[darren smith]

update

back together,
starts on the button first crank - great, before took 10 seconds or so, pump seal must have been passing
sorted injector leaks
sorted power steering leak- needed new rubber on top of pump banjo seal
since removing and refitting (gasket sealant on top of either rubber knock outs) rocker cover leak seams to have gone, however tiny drip of oil from turbo side when running only so looking for this one now.

but- the idle issue is miles better but when cold still fluffs every 10 seconds or so and does it within seconds of starting up, revs start to drop from 750 then a little miss fire and black smoke then engine revs climb back to 750. the warmer it gets the less It occurs, and over 1000 revs hardly noticeable.

when cold in a gear with transmission drag issue is more pronounced, when warm problem gone.

now a little lost - my thoughts either fuel filter housing/ feed hoses or the fuel pump could be iffy. anyone have any other ideas?

[darren smith]

update with possible success

changed the fuel filter and housing no better-- but

went through pocuk searches on issues, found one about the MAP sensor and its manifold filter which can give the same issue I have. Filter seamed clean but gave a good blow through with brake cleaner and compressed air. thought plastic housing was passing but could be my imagination as there was no sign of oil blowing past and re sealed the steel rim to the plastic outer. changed the MAP sensor for new mitsi one from Ebay. only £15 or so

put it all back together left battery disconnected over night, started on the button, my heart sank as it fluffed a couple of times in a minute after starting and then to my relief its never done it again since. even with air con off and on and in drive with drag and engine cold . interesting thing when using "choke" the car is now regulating revs back down to 750.

just shows posting issues and experiences does help others-  keep up the good work!

[darren smith]

issue has returned not as bad  

when warm everything fine

still its miles better than before, I am convinced its air getting into pump. within seconds of starting there is a hick up.

message for Mark3 can these electronic pumps draw air in from other internal areas not just the front seal?

changed stack pipes was pin holes around feed connections again an improvement, new filter and housing no difference

going to fit a clear hose from filter to pump to look for air

[darren smith]

update

still looking- put clear hose on feed to pump, no air until we have the hick up then it seams to somehow suck a small pea sized lump of air in, (back pressure from pump on the diaphragm?) this happens on the both the OEM filter housing and a new replacement. once hick up stops no air bubbles at all.

looking at previous posts and from NZ and AUZ fuelling issues seams to be common on the edc pump on Jap imports, together with the engine management light coming on, I didn't have the light on before but have now since I have refitted a EGR valve to stop excessive smoke.

so after much searching found a second hand pump, put it in - and it didn't even start with not even a hint of a catch, (now in dispute with an auction site) put my old one back in (getting quicker at getting these out now down to hour and half - takes a little longer to get back together though) and she fired up first time and was glad to have my little hick up back! proves the other pump was duff.

so the hick up is back- still only when cold, and every so often when going between D and R so a little "choke" at 900 revs until warm.(idle reset etc doesn't make any difference)

seams to be a common issue so after going through everything and people having the same issue I am convinced we have worn internal seals in the pump causing the issue,  and as the engine warms up the heat is taking up the seals and the engine can put up with slight miss fuelling when warmer and or at higher revs.

anyone know of the best places to send the pump away for a recon?

thanks

[NDZ]

Had this guy bookmarked for a while but not used myself

Diesel Bob