Offroad-Express

Hi there. Been reading through a lot of past threads over the last few days to try and diagnose my s****y Terrano. It's a 95 D21 TD27 auto. Lots of great stuff on here but haven't quite found what i'm looking for. Was hoping to pick your brains for some opinions.

Symptoms are that is smokes a hell of a lot of black (that I can see) smoke and is completely gutless on any sort of gradient. (Overtaken by a 16 wheeler not long ago ) I know they aren't a speed machine as standard, but it refuses to do more than 90 most of the time and maxes at about 60 up any decent hill. She does about 110 with a tail wind downhill...aaaaaawwwwwww yyyeeeaaahhh....

Since I got it about a year ago, I've had the leaky diesel pump reconditioned and the injectors reconditioned aswell. That didn't make much difference Boost test was done and reported the right amount apparently.

Is there anything obvious that I should be looking at here. Wondering if the exhaust has a part to play in this? Not being very mechanically minded, it would be great to hear some opinions of those in the know before I fork out any more moolaa...

Cheers. Sam.

i would get a cylinder leakdown test done td27's can pop heads at random ,and make sure you get a diesel outfit to test it ive seen what happens when people use petrol compresion testers on diesels haha boom.
thats my dollar

efi pump or mechanical ?

block off egr if its got it.
otherwise first thing that comes to mind is injection timing is out.

dave_ln130 wrote:i would get a cylinder leakdown test done td27's can pop heads at random ,and make sure you get a diesel outfit to test it ive seen what happens when people use petrol compresion testers on diesels haha boom.
thats my dollar

Please explain?

As mentioned, block off the egr valve (the bit that links up behind the exhaust manifold and goes round to the intake manifold.

It is highly likely you will find that the intake manifold is full of soot buildup so much that no air can get into the cylinders anymore which will give you the low power and big smoke clouds (which is unburnt diesel) You will need to remove this and clean it out with some sort of solvent.

Also check and make sure your exhaust system is in good condition as running this poorly for a extended period of time it will probably be sooted up

Hope this helps.

Cheers

-Sketchy

How does auto seem? Just that it might not be engine lacking power, rather the auto 'sucking' the power. Also, could pay to check brakes aren't tight (jack and spin wheels make sure they are free), and that front hubs disengage. It can suck a lot of power to spin them all the time.

How new is your air filter?
And fuel filter?

You also could try undo exhaust pipe at front, and take that for a quick ride to see how much difference it makes.

My guess would be the exhaust and/or the intake manifold full of gunk. Remove ALL the emission gear (EGR). I reckon I would have it roaring along in 1/2 a day if the compressions are ok
Diesels work well with some very simple principles, free flow of air in and free flow of exhaust out.
Disconnect the S bend at the turbo (temporarily) and the exhaust at the first flange after the turbo dump pipe and try that.
Sketchy is right on the money
Cheers,

Lynx wrote:

dave_ln130 wrote:i would get a cylinder leakdown test done td27's can pop heads at random ,and make sure you get a diesel outfit to test it ive seen what happens when people use petrol compresion testers on diesels haha boom.
thats my dollar

Please explain?

maxed out and the needle tip bent on the stop point because of the extra pressure (i assume the extra pressure ) and poped the hose it was on only just

Some very helpful info! Cheers!

Compresion test was done before I had the diesel pump reconditioned and checked out ok.
(95% sure pump is mechanical).

The air filter seems sweet. Took it for a blat up the road without it and noticed minimal difference.
Fuel filter seems relatively new too.

I will definitely look into the exhaust system then. Am I right in thinking that blocking off the EGR valve will stop the smoke but do nothing to power?

Slowly checking things off the long list...

Cheers for your input! Much appreciated!

squid61 wrote:Am I right in thinking that blocking off the EGR valve will stop the smoke but do nothing to power?

From what I've heard, the actuator can get stuck open which will be cycling the exhaust gasses back through intake continuously, So it can definitely help with power by blocking them off.

Good luck

Is it an auto?
Does it run ok (ish) up to a certain RPM and them burble and smoke when you try to get the RPM higher?
(If it does PM me so I can quickly post a reply)

Just thought I would say, finally blocked off EGR as well as fitting another turbo after screwing my old one (muppet). Exhaust manifold didn't seem that dirty. Performance is much better. Does 90-100 up hills, no way could it do that before...
Also got more power taking off, as well as it idling a lot better from cold.
Didn't do too much in terms of smoke though. Was told next on the list would be to check valve clearances... Slowly ticking that list...
Cheers.

if its blowing heaps of smoke esp when turbo is boosting i'd seriously look at lowering the fuel levels or up the boost. Deisels don't like too much fuel. It tends to melt pistons.

I'd look into the intake manifold too. Valve clearances wont make that much difference. like was said earlier it would pay to get the pump timing checked out.

buy one of these http://www.trademe.co.nz/motors/car-par ... 362274.htm

and you should be able to sort it your self

^ haha, if only it was that simple.

youll be suprised.
ive got the same manual
it shows what to adjust etc
black smoke is overfueling/running rich mixture
with diesels, when running rich mixtures you will over heat engine
petrols are the opposite.
we had this td42 patrol in at work, smoked more than bob marly
at the back off the pump on them there is a cover over a mixture screw
pop the cover off and loosen the nut on it, then turned the adjuster screw anti clockwise (i cant remember which way im sure someone will correct me)
until you only get abit off black smoke under load. you want have to turn the adjuster screw heaps