What did you do to your P2 Volvo today?

[dikidera]

That is the thing, all of a sudden after shuffling around the electrical installation it started working again. And today, specifically just now I cold started the car after letting it cool down overnight and it is still working correctly. I think if I had problematic timing it wouldn't all of a sudden start working again. The only weird thing is there is this weird sound coming from the general area of the VVT hub. Maybe the belt is on too tight so I will redo the tensioner correctly and see if it goes away.

So far taking all clues into account means the issue was and likely will be again an electrical issue. The problem now is the VVT solenoid is either dead or the harness for it is still shorting somewhere.
I have to remove the VVT solenoid to measure it properly and use a battery to active the piston. VIDA says resistance of 3.7-11 ohms should be the normal reading.

The grinding noise was maybe the VVT solenoid being erroneously activated due to the short in the electrical installation. I don't know what damage might have occurred.

[npexcept]

Last night I pulled the head off of my D5244T to repair the damage, that the previous owner did to the injector clip threads.
Also giving it a good clean with a walnut blasting and ofc new head gasket. Have yet to measure if the head is bent, but I'm optimistic.
Compression was good all around (24-26 bar, 350-377 psi). 2 pistons show signs of detonation (craters), but thats fine. No damage to the sleeve.

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[ZionXIX]

350 psi for compression? Is that higher than stock?

[npexcept]

350 psi for compression? Is that higher than stock?

Did wonder too.
Could not find the nominal compression for that D5244T (yet).
Engine has either 125k or 190k miles on it. Pretty healthy compression for both mileages.

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[BlackBart]

That is impressive that a head gasket can handle that. The shape of the pistons and combustion chambers is really interesting - completely flat across the valve faces.

[jonesg]

took 2 hours but the cat downpipe is in and mounted on the rubber hangers.

[jonesg]

That is the thing, all of a sudden after shuffling around the electrical installation it started working again. And today, specifically just now I cold started the car after letting it cool down overnight and it is still working correctly. I think if I had problematic timing it wouldn't all of a sudden start working again. The only weird thing is there is this weird sound coming from the general area of the VVT hub. Maybe the belt is on too tight so I will redo the tensioner correctly and see if it goes away.

So far taking all clues into account means the issue was and likely will be again an electrical issue. The problem now is the VVT solenoid is either dead or the harness for it is still shorting somewhere.
I have to remove the VVT solenoid to measure it properly and use a battery to active the piston. VIDA says resistance of 3.7-11 ohms should be the normal reading.

The grinding noise was maybe the VVT solenoid being erroneously activated due to the short in the electrical installation. I don't know what damage might have occurred.

the noise could be the tensioner, the water pump , vvt hub or the idler pulley.
if you remove the belt you can spin each one.

[volvolugnut]

350 psi for compression? Is that higher than stock?

Did wonder too.
Could not find the nominal compression for that D5244T (yet).
Engine has either 125k or 190k miles on it. Pretty healthy compression for both mileages.
20240103_114429.jpg

Haynes paper manual says 24 to 31 Bar Normal, 22 Bar minumum for DIESEL engines such as the D5244T. That has 120kW (163 bhp).
Looks like some of the carbon build up may have raised the compression.
volvolugnut

[dikidera]

That is the thing, all of a sudden after shuffling around the electrical installation it started working again. And today, specifically just now I cold started the car after letting it cool down overnight and it is still working correctly. I think if I had problematic timing it wouldn't all of a sudden start working again. The only weird thing is there is this weird sound coming from the general area of the VVT hub. Maybe the belt is on too tight so I will redo the tensioner correctly and see if it goes away.

So far taking all clues into account means the issue was and likely will be again an electrical issue. The problem now is the VVT solenoid is either dead or the harness for it is still shorting somewhere.
I have to remove the VVT solenoid to measure it properly and use a battery to active the piston. VIDA says resistance of 3.7-11 ohms should be the normal reading.

The grinding noise was maybe the VVT solenoid being erroneously activated due to the short in the electrical installation. I don't know what damage might have occurred.

the noise could be the tensioner, the water pump , vvt hub or the idler pulley.
if you remove the belt you can spin each one.

Water pump is INA and was replaced that very day where all this happened. All the pulleys are brand new, 7 months old. I think the timing belt tensioner is on too tight. I will try back it off hopefully not becoming so loose as to mess my timing, but I will make the appropriate markings just to be sure teethwise it's fine. But yeah the noise is coming as if from the VVT as if it's struggling to turn(without the vvt solenoid connected). As if there is resistance and it's whining.

I have more information, the 12v line that feeds a few components including VVT of the car is shorting to gnd. I am very positive, although I am still not certain HOW it was connected to injector for cyl5 unless the short to gnd was causing a weird affect on voltages for other components. Additionally after pulling fuse number 5 at the time the car also didn't want to work which should have prevented the short. It may be that there is more than one short.
Somewhere in the harness between the alternator and fuse box there are wires probably ripped and touching.

Any advice on what to do with the crumbling electrical installation? The wires themselves are pretty hard, they almost feel like they might snap.

[ZionXIX]

350 psi for compression? Is that higher than stock?

Did wonder too.
Could not find the nominal compression for that D5244T (yet).
Engine has either 125k or 190k miles on it. Pretty healthy compression for both mileages.
20240103_114429.jpg

Haynes paper manual says 24 to 31 Bar Normal, 22 Bar minumum for DIESEL engines such as the D5244T. That has 120kW (163 bhp).
Looks like some of the carbon build up may have raised the compression.
volvolugnut

Ah, I didn't realize this was a diesel model. Now it all makes sense. Diesel engines operate entirely on compression and have much higher pressure than gasoline engines.