P38A All smoke, no poke >_<

Hi all,

Wall of text incoming but could really do with some help on this!

I have a '98(WA) pre EGR diesel. Starts fine hot/cold, not lumpy, idles fine. Drives ok, until there is ANY incline or firm acceleration and any shred of power/speed disappears in the big black cloud of smokescreen that pours out the back. It was running ok with no power issues, pulled well etc. but the thermostat was shot, needle wouldn't go over the cold line unless you had it on full throttle from 70mph.

So I set about replacing the thermostat and had a little mishap when starting it back up afterwards... Fan decided it didn't want to play with the engine anymore and took it's ball home - through the radiator... In trying to remove the old rad I removed the intercooler hose (passenger side). Realised that I didn't need to remove it to swap it(though the intercooler rad does need replacing at some point, it's bowed in on the top?), and put the hose back on.

Bought it a new radiator, got it all back together etc. Took it out on it's first trip out and it was fine at low speeds cruising round the estate to make sure it didn't overheat straight away. Headed out onto the main road to give it some power and the intercooler hose shot off with a pop and a cloud of smoke. <_< On that initial acceleration and subsequent driving it seemed a lot more underpower, but I hadn't noticed clouds of smoke. Did a ~2hr trip like that. On the return trip it was the same for about 20mins, then power took a nose dive and the smoke started billowing..

Since then it has been as above, if I get past about 2k RPM - smoke, no poke. If I accelerate hard - smoke no poke. Any strain on the engine it's the same, struggles to get up hills.

Intercooler hose and clamps for that one have been replaced and it doesn't come off anymore. I have checked the MAP return hose and while it looks in rough shape(new one coming to replace), it is connected both ends. If I push it to the edge before it looses power/when it does I have noticed there is sometimes a very slight whistle but I have no idea where it could be coming from.

Connected Nanocom and it shows:
FUEL FLOW VALUE OUT OF RANGE
Type: INVALID FAULT, MAJOR FAULT, LOGGED, INTERMITTENT
RPM = 79
WATER TEMP = 53
OCCURANCE = 15

Reset and checked after more smoke and it comes back.

Now I don't know if this is side effect of something being changed by previous owner rather than fixing the cold running; Or that either the something in the air intake or the fuel delivery has failed.


Any help greatly appreciated!
Macos

Have a check for splits in the turbo hoses as that will whistle, and check the inside of the hoses for delamination they have a habit of collapsing inside.

brianp38dse said:

Have a check for splits in the turbo hoses as that will whistle, and check the inside of the hoses for delamination they have a habit of collapsing inside.

Click to expand...

I tried to have a look at the other hoses this evening. The long one has already been replaced, I think there are two others? Though I'm not sure how to get to them. Will try and work that bit out tomorrow

On mine it was the elbow off the turbo that delaminate may be to do with the heat, it is not easy to get to but doable.

brianp38dse said:

On mine it was the elbow off the turbo that delaminate may be to do with the heat, it is not easy to get to but doable.

Click to expand...

Just ordered a replacement for that one, the other one I replaced looked like trash especially compared to the replacement. Figure it will be worth getting a new one on that too.

You said the intercooler is bulging and the hose popped off? Have you flushed the intercooler and made sure it has good airflow?

Top of rad has been known to bulge and might well do with a shot thermostat.

Also check the engine temperature sender for the ECU.

@brianp38dse, I've checked all 3 of the pipes and there's no delamination in any of them but they were quite soft. Replaced sbend and elbow.
@Grrrrrr, my mistake, it's not the intercooler that is dented, it's the rad in front of it. Haven't flushed it yet, will try and work out a way to do that at the weekend.
@Datatek, i'll check this when I'm out tonight, though the temp needle is solid at 12oclock now.

Undo SLAM panel, really carefully remove the air deflectors, Undo hoses and intercooler should slide out. I just petrol to flush then leave it in the sun.

Macos said:

@brianp38dse, I've checked all 3 of the pipes and there's no delamination in any of them but they were quite soft. Replaced sbend and elbow.
@Grrrrrr, my mistake, it's not the intercooler that is dented, it's the rad in front of it. Haven't flushed it yet, will try and work out a way to do that at the weekend.
@Datatek, i'll check this when I'm out tonight, though the temp needle is solid at 12oclock now.

Click to expand...

The temperature sensor for the ECU is not the same as the sensor for the gauge.

Grrrrrr said:

Undo SLAM panel, really carefully remove the air deflectors, Undo hoses and intercooler should slide out. I just petrol to flush then leave it in the sun.

Click to expand...

I find Acetone better for cleaning the crud out of intercoolers. Make sure it's all out including vapour before putting the intercooler back.

Readings from Nanocom last night idling at temp.

Need one of the gurus like Wammers. Cannot see much wrong there although the fuel quantity current is low. Guess it would be at idle.

I've noticed that the boost gets up to 180kPa before it dies isn't it supposed to only be at 120(1.2bar)? Then when it's hitting the 45mph mark, where it likes to change gear(auto), it just lets go, whitish smoke, no power, boost dropped to less than 95kPa.
Any thoughts @wammers?

Think you're right. Not sure what mine maxes out on but don't remember the boost being that big. Dropping to 95 is damn odd. That's below ambient so either the sensor is stuffed or something is sucking. Turbo hoses fine and not delaminated inside?

I have the same (pre egr) machine, although it's a manual.

I've not had this issue, but if I did I would suspect an inlet blockage to the turbo - usually a hose, as has been suggested.

A quick way of checking this would be to simply remove the main feed hose to the turbo and go for a quick drive around the block to see if that sorted the problem. If it does then you know where the issue lays (ie. pre-turbo).

If this didn't sort it then I'd try removing the main feed to the inlet manifold (ie post-turbo) and attempt another test run. This would have very little power, but if it didn't smoke then likely as not it'd point you towards the air feed path post turbo but pre manifold.

One more thing - I assume you've checked there's no issue with the air filter or inlet?

Grrrrrr said:

Think you're right. Not sure what mine maxes out on but don't remember the boost being that big. Dropping to 95 is damn odd. That's below ambient so either the sensor is stuffed or something is sucking. Turbo hoses fine and not delaminated inside?

Click to expand...

Good call mate. If manifold pressure falls below ambient the inlet is being restricted and the engine is sucking causing a partial vacuum in the manifold. He needs to check turbo hoses internally.

The pipe that feeds the turbo ,should be a hard plastic elbow ,if its a rubber hose there known to close under vacuum ,they were changed ,,,someone on here will know the year

dubbleRR said:

The pipe that feeds the turbo ,should be a hard plastic elbow ,if its a rubber hose there known to close under vacuum ,they were changed ,,,someone on here will know the year

Click to expand...

FWIW Mine's a '96 and it has the hard plastic pipe.