another loss of power/acceleration thread

[jamiesmack]

Hi all,

I know these threads are a regular occurrence, and I apologise for making another one. I've had a couple of issues that I haven't seen mentioned in the other threads so thought the problem might be related to these.

I noticed recently that the engine was making a whistling / whooshing noise getting louder as I accelerated. Whether this is related to the main issue or not I don't know.

A few weeks ago as I was driving at about 50mph, I noticed the car wouldn't accelerate, I could maintain the same speed (on the flat) but not accelerate. If I moved down the gears the speed reduced accordingly and I couldn't speed up even with my foot flat to the floor. The revs weren't really going up either. I pulled over for a while, and when I restarted the problem had gone away.

Since then, I have been getting the loss of power more & more frequently. The weird thing is, when I get the power loss, if I take my foot off the accelerator & clutch and flick the ignition off & on, I have power again for a while, like it has been reset???

Any ideas?

 

[hd3]

I noticed recently that the engine was making a whistling / whooshing noise getting louder as I accelerated.

check the post-turbo / intercooler hoses for splits ..

 

[jamiesmack]

Yeh, that was recommended to me. Ive replaced them with some silicone hoses just to be safe, but the old ones didnt seem too bad or have any noticeable splits

 

[hd3]

Ive replaced them with some silicone hoses just to be safe, but the old ones didnt seem too bad or have any noticeable splits

double check the connection points

when i installed mine .. i didn't properly tighten the lower left joint where it exits the intercooler
or more to the point .. neglected to make sure the jubilee clip ( or t-clamp ) was properly positioned behind the lip on the intercooler bit .. the hose blew off sounding like a petrol engine backfire or gunshot .. as i was climbing a steep hill ..

also .. when i installed the silicone hoses .. i thought some of the supplied t-clamps were too big ..
and felt a tad loose even tightened all the way .. so fitted some smaller ones

and maybe check the pipe/hose that directly exits the turbo into the intercooler
i think they have been known to fail .. even though it looks more robust than the standard intercooler rubber hosing ..
( have read posts where that hose/pipe has delaminated inside )

i can't offhand .. right now .. think of another way the engine would make a whistling/whooshing sound
and loose power as well .. must be the pressurised air post-turbo leaking somewhere
~~~
although i suppose if there were an intake leak .. after the maf sensor and pre-turbo ..
it might have a similar effect .. but .. if that were the case .. lack of airflow across the maf would reduce fuel injected ..
which would reduce turbo pressure .. .. mmmmm .. .. no idea what would be the audible symptoms :-/ ..

 

[Epicuser]

As above. Make sure the hoses are tight. Mine were whistling until I re tightened them. Been fine ever since.

 

[jamiesmack]

Thanks for the advice, I'l check how tight they are when I get home.

Any ideas on why flicking the ignition off & on (it doesn't even need to be enough to cut the engine) brings the power back?

 

[Nodge68]

Any ideas on why flicking the ignition off & on (it doesn't even need to be enough to cut the engine) brings the power back?

Faulty lift pump or relay, at a guess?

 

[jamiesmack]

Right, ive been and tightened all of the clamps, there was a little bit of slack, but not much. got 500 yards down the road & power died again

I tried to listen to the noise a bit closer tonight, it gets louder & louder as I go up the revs, and is really loud and whistley when at high revs.

Does anyone have any more suggestions as I'm stumped

 

[hd3]

wondering if your turbo vane actuator bits are getting stuck ..
i.e. stuck on full boost position
no idea if one would actually hear that .. or to what extent ..
but .. it would cut the power when the map sensor reads an overboost occurence ..
and not sure if a dashboard warning light would come on either
~~~~~~
so : .. no smoke symptoms .. or warning lights ?
~~~~~~~

Any ideas on why flicking the ignition off & on (it doesn't even need to be enough to cut the engine) brings the power back?

to figure that you'd need to know what exactly happens when the electric power is cut
.. i'd guess any sensor signals would be lost momentarily ..
.. might be a connection to the turbo vacuum solenoid .. i.e. telling the ecu what position it is in ..
maybe it does reset .. from the ecu's pov .. signals from various sensors ..

don't know :-/ .. can only speculate ..

 

[jamiesmack]

No warning lights at all. It is a little bit more smokey than it used to be, but not excessively so.