S40 diesel problems
 

hey all, my first post here as you were recomended by a good known autoelectrician.

i have a customer with an s40 1.9TD. T3 engine. we replaced his cam belt and done a service a few months back and then a few weeks later his car just died in the middle of a dual carriageway and failed to restart. he was towed by the AA who shruged there sholders and i then had a look. so far we have rechecked all the timing, checked all sensors we can without diag, replaced the crank sensor, replaced fuel pump and also tried to scan with 4 different tools, including DICE, none of which will even comunicate.

now the car turns over but there is no fuel being pumped from the HP pump to the rail. there is no other electric pump anywhere on the car, the lift is fine and so is the filter / housing. we get fuel air free into the pump then when we go to start it will kick and run for 1/2-1 second then carry on turning over. theres no engine management light on either.

would anyone have any ideas? it worries me that we cant comunicate with the ecu at all aswell, however we have checked all cables and everything is ok.

thanks, jez

Silly question but did you purge the air lines from the fuel filter to the pump using the fuel priming bulb? I would also check the vac lines behind the inlet manifold incase you have any splits etc, mine had a connector that snapped off which caused it to go into limp home mode (but not throw a code) if there is a damaged hose or connector back there it might cause no end of issues - they get brittle as they are sitting over the exhaust and turbo and can crack mid drive as mine did.

hi, yes done all that, no air at all up to pump. also checked all connectors around that area :(

I had a diesel, might not be true for Petrol cars, but I had a problem with a camshaft pulley pin. There is a groove on the camshaft where pin slides in and if it is broken off it would mean that the fuel is not supplied to the engine as the camshaft sensor is registering a different pattern/position than it used to be. In simple words, there has been an engine damage or the timing belt has slipped by a tooth or so causing an engine to ''shut down'' to prevent further damage. That would be the last 'thing that I would check as the timing belt has to come off in order to remove the pulley.


On the left: Broken off pin. On the right: Pin like it is supposed to be.
http://www.bildites.lv/images/c02sc68ff5y8hihotxg.jpg

Is the immobiliser light on by any chance?

I remember a silar problem with a 2.0T where the immobiliser light was on, which will cut off the fuel to the car. DICE would not communicate with the car either. In the end, it was a problem with an earth wire going into the ECU

I'd have said it sounds like immobiliser. Not letting it fire up.

But if it won't talk, might be worth chucking it at Volvo for a communication attempt.

If the ECU has gone, that would stop it starting for a number of reasons I imagine.

Cheers,

Daniel

wires under radiator worth a check to illiminate

BIOTOXIC- we changed the belt again when we changed the HP pump, didnt notice it broken nor did the old marks move. we re-locked it as before and all ligned up. itll run on easystart aswell perfectly fine.


the imobilizer light isnt on nor causing a problem and all light on dash are normal (batt, seatbelt etc etc....) no engine management light staying on, this goes off after a few seconds. ive checked the earths to the ecu in the engine bay, anyone else know of any bad points to look for earths? also whats this about the radiator loom?

also forgot to mention, when we get it air free to the HP pump, we can get all of about 2 seconds of good fuel pressure before it cuts off. it happens the same amount of time for everytime we rebleed it etc. and no its definately not an air leak or faulty filter housing. its as if its getting fuel then something tells it to cut off and then the system will drain down with the rest of the cranking.

Only other thing I can think off is the fuel pressure regulator, located on the high pressure fuel pump.