2.8 diesel engine power problems

I just bought a 2.8 litre Hiace Cruising Cabin conversion - took a real gamble with a guy on eBay - he wasn't completely honest about quite a lot of things, but as the dust has settled it looks like I've still had a good deal but not as good as he had pitched/lied (depending on how generous you want to be . . .)

I took it for a main dealer Toyota service in Cardiff, great service, real pros, good coffee etc, expensive for sure but you do then get peace of mind after dealing with someone dishonest - vehicle is in very good condition having just had its 60k miles service but needs a few things done:

1. all the belts need replacing (vendor lied and said they were all replaced last year) (£200 est)
2. exhaust downpipe is blowsy and needs replacing (£400 est)
3. cabin heating switch fix (£89 est)
4. wheel socket joint worn (£500 est)

Toyota Cardiff said they normally refuse to service imported Toyotas because their computer systems can't work with the parts, but the engineers wanted to work on "The Event Horizon" as it was a nice technical challenge and so I have the reassurance of that to go on with . . .

HOWEVER . . .

one issue I raised with them for investigation was the fact that for a 2.8 litre diesel at 60k miles it really didn't have the power I would have expected - meaning acceleration actually - and they suggested that sometimes japanese imports have been power restricted back in Japan, but not by a standard method and they didn't know how to analyse this or fix it . . .

So, can anyone give me useful information on this? I'd like a bit of oomph from this big engine - its thirsty enough! So far its a steady 65mph on flat motorway but slows to under 50 going uphill :-((

The performance that you are getting is very similar to mine. It will cruise at up to 115km/h but that doesn't do anything for the fuel consumption (12.5 litres/100km) and any hill drops it back rapidly. It is certainly very different performance to the 3litre turbo in my Prado.
When I bought it, with 65,000km on the clock, it was the first time it had been registered in Australia. It couldn't get over 100km/h. After a thousand or so kms of my highway driving the performance picked up to what I have now. I'm guessing that its previous life was one of short and slow trips which coked it up a bit.
If what you were told about Japanese power restrictions is correct it would be very interesting to find a solution!

Hi,
(me again.. :-) )

That seems wrong to me. I have a 2.8 n/a too and, while it's not a fast car, it'll cruise along quite happily at 70+ on the flat. There's not a lot of power in reserve and it's pretty thirsty (see several threads on this board comparing fuel consumption figures) but it takes a pretty big hill to force the speed down to under 50- It's been most noticeable going over the M62 with four of us (2+2) and a faily well loaded van towing a half- tonne trailer with two small boats on it, or on some of the well-known hills in the Highlands (e.g. Cairney Brae or Drumochter on the A9).
Unless there's a hill or a headwind, though, we need to remember that we have the trailer on and shouldn't be going over 60... the van will happily run faster than that if you let it.

This is, however, a HiTop conversion on a Super-long wheelbase chassis (HiAces come in three lengths-
Standard, Long, Super-Long), so it's as big as they get.. and it has the P/T 4WD running gear, too, so it's no lightweight vehicle! If The Event Horizon is a low-roof standard body you'll have a bit less weight and drag, so you should have more in reserve at cruise...

I think the 2.8 N/A engine is rated at about 90bhp and the "performance" I get seems consistent with that. It's always nice to have more power, hence the appeal of the 3.0l turbodiesels, but I'm happy to have a relatively simple, low-stressed engine and prefer the Part-Time 4WD setup on the earlier vans to the later AWD one.

I don't know enough about the mechanicals to advise you on how to fix it, I'm afraid, but I do think there's something not quite right. Could be that it's just "choked up", as MalL suggests, or it could be that some sensor or input to the engine-management isn't worlking... I just don't know...

Cheers,
W.

Thanks guys - I haven't really given it a long full throttle run yet, because I'm waiting for the belts to all be changed out on Thursday - then its off on annual old boys rugby tour this weekend and a long drive down the M4 might serve to clear the pipes etc - I'll let you know how it pans out

I took it into Halfords for a supply and fit of the super bright headlamps you can get these days - and they couldn't work out how to access the interior of the lights - much head scratching!! Any idea?

Also, on the 4WD thing, this is my first 4WD car - a few Q's if thats alright?

1. the front wheel hubs have turny things that say locked and free - the garage said its something to do with going off road and the from differential - any ideas?
2. what are the disadvantages of having 4WD engaged all the time?
3. likewise with the overdrive - when should I switch it off and why?
4. the low ratio gearbox leaver - when to engage the low ratio? What is the effect on the top speed in low ratio?
5. at the top of the gear selector housing is a red plastic button - what does it do?
6. in full lock in 4WD the car makes a light mechanical grating/clunking noise - the Toyota engineers said this was normal for 4WD's - is it? What is it exactly? I'm always happier if I know the mechanical explanation for something!

There is a very helpful post somewhere about getting to the lights. You start by removing a screw from inside the front doors which enables removal, in turn, of indicators, turning lights, etc until you finally get to the headlights. I think part of the grill has to come off to - it's a while since I've done it.

On 4wd -
You would be aware of why differentials are needed on axles - because inner and outer wheels are rotating at different speeds when cornering. The same applies between front and rear axles, so for full time four wheel drive on all surfaces a third diff is required between those axles. Many 4WDs do not have this so can only safely use 4wd on soft surfaces that will allow wheels to slip and avoid damaging transmission components.
1. If driving on roads with four wheel drive not engaged the front diff is being rotated by the wheels. This creates a bit of extra drag and wear. By unlocking the front hubs this is avoided. Unlock for normal driving, lock if using 4wd on soft surfaces.
2. Damage to the entire drive train unless the vehicle has a centre diff or a fluid coupling which allows slipage. I haven't been able to find out specifically what the Hiace has so play safe and stay in 2wd.
3. I usually leave overdrive on all the time but disengage it for any extended downhills. The engine braking places less reliance on wheel brakes. Most of my driving is open highway - you could leave it off if you are at lower speed, stop/start suburban driving.
4. Low ratio is usually only needed if you really need to crawl along over rocks or scale steep inclines - the Hiace isn't really suited for this kind of work anyway. Try it out on loose gravel or similar to see how it affects speed - it drops it way down.
5. Not familiar with that one but if it's like the Prado it could be to allow shifting transmission while the key is turned off.
6. Mine does the same - I think it is noise from the CV joints. Not sure that it is exactly "normal" but I'm not going to do anything about it unless it gets a lot worse.

Thanks MalL - thats a great dollop of useful info in there that will save me from destroying the transmission which is EXACTLY what would happen if I followed my basically simian instincts to experiment in a knowledge vacuum!!

So best for UK Roads is 2WD, with the front hubs unlocked :-)

Am I right in thinking that the 4WD just doesn't work at all unless the front hubs are locked then?

cheers

Hi,
4wd info:

https://hiace-super-custom.forumotion.com/t2122-how-is-power-transmitted-from-rear-to-front-in-awd#11947

& also:

https://hiace-super-custom.forumotion.com/t2189-4wd-drive-spanner#12215

Overdrive (read down):

https://hiace-super-custom.forumotion.com/t1979-overdrive?highlight=overdrive

Low ratio: see 4wd above

Red button just allows you to move the shift lever without inserting the key and putting your foot on the brake. eg to get out of "Park"

Grinding at full lock- mine does that too. I don't like it but hope it's not a problem(!) Assume it's just the CV-joints being twisted too far.

Cheers,
W.

Django-Wildheart wrote:

Thanks MalL - thats a great dollop of useful info in there that will save me from destroying the transmission which is EXACTLY what would happen if I followed my basically simian instincts to experiment in a knowledge vacuum!!

So best for UK Roads is 2WD, with the front hubs unlocked :-)

Yes, until it snows.

Quote :

Am I right in thinking that the 4WD just doesn't work at all unless the front hubs are locked then?

yes, that's right, the front driveshafts will turn but they won't turn the wheels unless they are connected to them.


If you expect to need 4WD then lock the hubs but leave the 4WD system off. When it gets slippy (eg you're going up a slushy hill where the gritters haven't been) then you stop and engage 4WD using the button on the dash. When you get grip back turn it off- you should notice that the van doesn't want to go round corners if you have 4WD engaged. Getting it to dis-engage if you've already driven on dry tarmac can be tricky, as you get "transmission wind up", where the prop-shaft is twisted because the wheels have travelled different distances...
If you need more low speed- control because you're crawling over obstructions, towing up a hill etc then you stop & engage low-ratio.
I assume that low ratio will work without 4WD but will put all the load through only half the drivetrain. If you need low ratio you probably want to spread the load!!

Edit (months later & a year after getting the van!): noticed this evening that there is an interlock that means you can only move the low-ratio lever with 4wd engaged...! So I guess that answers that question!!!

Cheers,
W.

Thanks for those links W, I'll be checking them out myself later.

Ah yes, icy roads - not something we have to consider much here unless travelling to the ski fields.

Amazingly thorough posting - Big Thanks

Hi People, with regards the clunking/metallic sound on full lock, it is most likely just the steering stops, they dry out and you get a hole load of clunging grinding usually when on full lock on a bumpy/ uneven surface , mine dry out every six months or so, a dollop of grease quiets them down for a while, if you put the van on full lock and look in behind the wheel it just looks like a bolt not fully done up with a lock nut (may have had rubbers on when new, but thick grease seams to last a few months) hope this helps

Thanks for that, I'll have a look.

Hi Django-Wildheart

Your story sounds very similar to mine. I bought a Hiace off ebay, about 3.5 years ago now. Was a little rough running when I got it (belts slipping and screeching and overheated) but a good service from an expect sorted it out and been bullet proof ever since. Even in cold weather having been left a couple of weeks it starts first time everytime. Mine is an LH129 model which I think is a super-long.

My van is certainly not fast! It slows down a bit on hills and autobox kicks down and you cannot help but thrash it a bit which it will take quite happily! Best to take the scenic route and don't expect to get anywhere in a hurry. The best fuel economy I have got is nearly 30 mpg on a good motorway run, but generally less than 25mpg. I think that it was better after good sevice when the auto gearbox fluid was changed. Does auto gearbox fluid degrade and result in further transmission loss? I chose a custom stainless steel exhaust from the downpipe back. It was good value compaired to the standard parts, but it is loud! I had one on my car and gave a noticeable difference in torque (staright through silencers), and I was hoping for the same on the van but couldn't notice the difference - only one silencer as opposed to 2 on car. Someone told me that if the restrictor was still fitted it would not exceed 60mph, but it will get up to about 80 down hill!

I have never used low ratio. I have used gears 2 and Low on occassion to provide some engine breaking going down steep hills - van is heavy so picks up speed quite easily when free wheeling in Drive! I have used 4WD only a couple of times to get across muddy campsites and its good to have that smug satisfaction that you're unlikely to get stuck.

Hi guys

Just about to fit snow chains to deal with the blizzards here in South Wales - lots of advice says that 4WD vehicles usually have the front wheels as the default drive wheels - is this the same for the Hiace or are the rear wheels the drive wheels when in 2WD? cheers

Rear wheels are the drive wheels - my 4WD has free wheeling hubs on the front.

What a nightmare trip I had yesterday - 500km, the temperature was 44C and pushing a headwind gusting to over 60km/h. The highway has frequent hills and on those the van's temperature rapidly headed for the red line necessitating slowing right down and turning the aircon off. Rest day today.

crikey - what a grim day's driving that was :-0

Its very lovely of you to take time after such an opposite style of stress to help me with my cold weather problem - thanks!

I only did it for the sympathy.