p0234-5b - no power

[richje100]

hey guys.
been having trouble starting the car in the mornings when really cold. no eml on so im sure i can rule out glow pulgs. battery has been tested under load & its holding the voltage so im sure i can also rule battery & alternator out.

i get error p0234-5b boost pressure control circuit positive deviation from my op-com reader
ive removed inlet manifold removed the boost sensor. the sensor wasnt that bad but the manifold was clogged so gave them both a clean with carb cleaner. while the inlet was off, the manifold behind it was clogged so took a day off work and set out to clean. took the manifold off and the swirl flaps. the swirl flaps where gunked up so thought "bingo" they couldnt have been opening & closing properly. replaced gaskets & fuel pipe and so on.

car started so thats a plus but im still underpowered in 3rd,4th & 5th gears. if the revs go beyond 3k or i hit 75mph i get spanner light and this was the code that gets registered everytime.

i still get poor start up in cold temperatures.
just wondering, when i was cleaning the boost sensor the little copper filament inside the cone seemed loose. i gentlys cleaned it with a paint brush but could see it moving but was still stuck to the unit. is it supposed to move like that?

also, im going to look at the diesel spill pipes as someone said these perish so wouldnt hurt to change these. ive checked the hoses for splits & they are all fine.
also thinking of following how 2 to clean the dti turbo solenoid just incase this will help.

oh, ive got a 2.0ltr dti 54 plate

[bobssignum]

Check all your intercooler hoses from the turbo down through your intercooler and back to the inlet manifold for splits or holes ,at the same time check your vacuum hoses and connectors for the same .
while your checking the vacuum hoses test them to make sure you are still getting a vacuum , it is only 0.7 bar from these hoses but you can usually detect it with a wet finger if nothing detected or one seems to have less suction then i would suspect that one of the solenoids is faulty

HTH regards bob

[richje100]

cheers bobssignum.
can all this be easily checked on top of the engine or get underneath? ive just given a quick squeeze on the hoses and cant feel/see any cracks.
also, when you say test them how would i do this? if i see a split then use my finger to test any air is that what you mean mate?

[bobssignum]

For the vacuum hose connectors its best to disconnect each one then when free twist and bend them to look for splits .there to small to test for the sound of leaking air .
for the larger inter cooler hoses get some else to put there foot on the throttle and increase the revs to 2000-2500 , and then compress the two main top two hoses in turn ,if there is a leak in any of these you will be able to here it .

[richje100]

the vacuum hoses these are the thin clear/black pipes connected by solid black elbow joints dotted around the engine?
when i took off the swirl flaps there was a block on the right hand side with a clear-ish pipe ahich i didnt want to pull to hard but couldnt come away easilu so i put a blacket over the engine & cleaned the swirl flaps almost in situ.

[bobssignum]

DSCF0004AA.jpgDSCF0003AA.jpgDSCF0002AA.jpgDSCF0001AA.jpgThe circular looking unit on the right hand end of the camshaft cover is the vacuum pump . see pic 1 the other pics show the various connectors for the vacuum hoses thatb should be checked . the last pic shows the actuattor/solenoid for the turbo , follow the hose down to the vacuum diafram on the turbo and check this connector also , this one is very susseptible to cracking as it is close to the engine block

[richje100]

top man, thanks for taking the time for these.
just remembered on a different note which i noticed yesterday, i followed this guide http://www.astraownersclub.com/vb/sh...d.php?t=191558 to clean the swirl flaps & egr. fill the car up to max yesterday but the fuel needle stayed between the full line & the next notch until about 10mins of driving it slowly went to full mark. got in this morning needle was back there but only done about 2miles. normally the needle moves off the full mark after about 60miles. could this be air in the fuel system? thinking of loosening the 4 fuel bolts again & getting diesel to leak from them.

[richje100]

top man, thanks for taking the time for these.
just remembered on a different note which i noticed yesterday, i followed this guide http://www.astraownersclub.com/vb/sh...d.php?t=191558 to clean the swirl flaps & egr. fill the car up to max yesterday but the fuel needle stayed between the full line & the next notch until about 10mins of driving it slowly went to full mark. got in this morning needle was back there but only done about 2miles. normally the needle moves off the full mark after about 60miles. could this be air in the fuel system? thinking of loosening the 4 fuel bolts again & getting diesel to leak from them.

[bobssignum]

you should not need to undo all 4 fuel lines only the fourth - the far right one ,as this is the last one to recieve fuel in the firing sequence

[richje100]

Thanks pal. If I replace the fuel spill pipes would I need to loosen te fuel lines again and crank it over or just swap the pipes over? Might not need changing but seeing as though I've got the bug wouldn't hurt to do .