Delica Canada | Mitsubishi Van Club

History:
Regasketed IP, new timing belts, new head and gaskets, new fuel filter, new ATF.

Problem:
Starts and runs fine ok but lie power until it gets up to temperature.

Symptoms:
EGT s are good.
When warm won't Rev above 2500, sometimes stumbles with white smoke.
Will idle around 650-700 with adjustment about 2/3 .

Possibly:
I'm thinking turbo or turbo wastegate!?
Is it worth its to close the wastegate manually, after disconnecting the arm?

Any other ideas??

It seems strange it's blowing white smoke, not black if it was your turbo. First thing I would do if your thinking turbo troubles is put a boost/vacuum guage on a t to the line running from your turbo to the top of your IP and then go for a drive and see if it's making boost (best done with two people so one can drive and the other can watch the guage, I also wear peltors (ear muffs and just leave the passenger seat up when I do it)) and how much. That will quickly diagnose if your making boost, how much your making and when your actuator is opening the wastegate. Alternatively you could climb under and give the actuator rod a pull, if you can pull it down (opening the wastegate) at all easily then something's up with that.
Before you hade that work done did you have any turbo symptoms? Who replaced the head and did it come from a reliable source? A 96 has a liquid cooled turbo which runs the engine coolant through it does it not? Are you losing coolant? Maybe a seal is gone in your turbo and now your sucking coolant into your intake air? Hopefully that helps? I'm no expert..

I agree with Trinker's thoughts: a failing turbo shouldn't cause white smoke or misfiring. White smoke is from poorly-combusted fuel, caused by being injected at the wrong time- and you *have* just worked on the injection pump...

I'm going to presume it's not the turbo. It's odd that it only shows up when it's warm. Does your injection pump have a cold-start doohickey? It'll be on the end of the advance plunger like so: ...though the appearance might be different. If you don't have one, that position just has a metal plate with two screws, and an o-ring behind.

I ask because that's the only thing I can think of that deliberately changes with temperature. If you have one, then maybe it's not assembled correctly.

Other things that can cause misfiring at higher speeds (but not necessarily when hot):
-Air in the injector lines (compresses and alters the timing). Give them a good bleed.
-Restriction in the tiny fuel screen in the pumps' fuel inlet banjo (if fitted. Changes the pump's internal pressure, which controls injection timing))
-Sticky advance plunger (mine was sticky from someone assembling the pump with silicone sealant. Ugh. All seals should go in dry.)
-Air leak from a damaged/improperly installed seal (usually causes hard starting though)
-Sticky/dirty injector- The little needle on the end is very delicate and will cause no end of troubles if the injector is dropped. They also don't like dirt in their fuel, was there any chance crud got into the fuel inlet?

Apart from those things I'd check all the things that were moved during the recent work. I'd be looking for fuel leaks, but also checking that everything is tight: A loose injector or delivery valve might be sealing fine when cold, but allowing air in when hot. A single head bolt that's not torqued could let air in. etc.

Had similar problem, had disturbed injectors as no.4 had a leak at seal in head so pulled them all to change seals (do when engine warm) They were tight to get out especially no.4 so suspect the injector body might have distorted and damaged, 4 new ones (not cheap) cured low power under load.

Thank you for your responses. I'll get back to you when I next get a chance to work on Ta-tanka

Bleed the injectors. No change.
Took for test drive and still lacking power.
THEN...Shuddering and rattling.
Intake rocker arm number one broke
Valve lash was correct-checked four times.
So, back to IP pump timing???

Any home timing hints please?

Bad injection pump timing can't break a rocker- I think you've found the source of your low power.

Was that one of your new rockers, or one you didn't replace? (or did your new head come with all new rockers?) If it's an old one, it probably had a crack in it that wasn't visible. That rocker flexing before breaking entirely would explain the low power. Time to replace *all* the rockers, and the shaft they run on, and check that the bolts holding the shaft down haven't stripped the threads in the alloy cam caps. (They're easy to fix with a heli-coil if needed).

If it was a new one I think you need to check your timing again (as well as checking the shaft and bolts) . When you installed the new timing belt, did all the timing marks line up perfectly? It's easy to slip one tooth on the crank sprocket while installing the belt and not notice, that's why they recommend turning the engine over (by hand) two full revolutions and confirming the marks still line up. When you check your timing marks, if one is a full tooth out it's probably just that the belt slipped during install. If it's half a tooth out, it might be a worn key or keyway on the crank.

Injection timing isn't all that critical. Ideally you'd set it with the proper tool, but I'm lazy and just set the injection pump to halfway in its adjustment range (which should run just fine), then advance it (bit by bit with a test run after each adjustment, not while the engine is running!) until the loud clattering at idle is kind of staccato- not constantly rattling, not quiet, but sort of sputtering. Then again, I'm quite familiar with what a properly timed 4D56 sounds like so maybe finding/making/borrowing the proper tool is safest.

It jumped a tooth.

Confusedone wrote:It jumped a tooth.

That'll do it. Bugger. I've done the same thing, but caught it before trying to start the engine. I think I skipped the "turn engine two teeth forwards before tightening tensioner" bit.

All fixed.
The lack of power was the IP needing to be nudged.
Ready for a road trip now!