Fuel issues

[Corey d40]

New member first post.
I have a 2008 2.5 Spanish built d40 and I lost boost pressure on my gauge. I started my ute one morning and when I drove out of the drive way it was sluggish and was blowing white smoke. It also stalled on me and would not start with out priming using the bulb under the fuel filter.I have replaced the boost solenoid,boost sensor,scv,turbo,intercooler,fuel filter,primer bulb i still have no boost pressure and the motor will only run if i rev it above 2000 or if I manually pump the primer bulb.I have blead the system but it keeps stalling.I have reset the ECU and cleaned the maf sensor but still won't run.
Can someone please help it's doing my head in.
Thanks Corey

 

[Old.Tony]

Hey Corey,

Try overpriming the fuel system until it leaks. I had this exact problem and it was one of the fuel lines that had started to deteriorate.

As for boost, there could be a couple of reasons why it's reluctant to boost.

Boost control is governed by the ECU (and reduced when gearbox is in neutral). The ECU controls the signal to the BCS (Boost Control Solenoid) mounted on the intercooler's hard pipe (engine bay left hand side, about a hand's width away from the alternator). Follow the vac line from the turbocharger, this goes directly to the BCS. Test the turbo and BCS in one easy step: remove the feeder vac hose that comes over the engine from its connector (seal this and photograph it so you remember where it came from). Now take the control vac hose off the turbocharger. Put the feeder vac hose directly on the turbocharger and start the car, get someone to give it a little rev (nothing over 2500rpm). You should watch the arm under the round gold widget that the feeder vac hose is now connected to.

If that arm does NOT move:

1) Check that feeder vac hose for damage or looseness. It may be losing vacuum somewhere (common).

2) Take the car for a drive and see how good the brakes work. If you have to stomp on the brakes, you have a vac leak inside the brake booster (rare, but has occurred).

3) Get a fresh piece of clean vac hose and put one end on the turbocharger. Suck on the other end (not "Stormy Daniels" style, of course) and see if the actuator moves and if it holds vacuum. The actuator may have a damaged diaphragm (has happened before).

If the arm DOES move:

1) Vacuum pump and brake booster are GOOD.\

2) BCS is likely at fault (common), BUT save yourself some time and money and check all of the other vac hoses first. I replaced mine (completely) - takes about 3m of 3mm vac hose (Supercheap sells this stuff) - and test again before giving up on the BCS.

3) Check the electrical connection to the BCS (unplug it and plug it back in to clean the contacts). Still faulty? Probably a bung BCS.

With a failed BCS you have two main choices:

1) Replace the BCS with another. Nissan want about $240 for one, but you can get Chinese replacements for around $35 on eBay and they DO work.

2) Replace the BCS with a Tillix/Dawes valve. I'm using a Tillix valve from https://www.tillix.com.au/product-category/boost-control/tillix-valves/ ($165) and never worry about it again (except for vac hoses). A little modification is needed to the turbocharger output pipe (the hard pipe before the baffle.

Sorry for the essay, but I hope I've covered it all.

 

[Jack0]

Hey Corey,

Try overpriming the fuel system until it leaks. I had this exact problem and it was one of the fuel lines that had started to deteriorate.

As for boost, there could be a couple of reasons why it's reluctant to boost.

Boost control is governed by the ECU (and reduced when gearbox is in neutral). The ECU controls the signal to the BCS (Boost Control Solenoid) mounted on the intercooler's hard pipe (engine bay left hand side, about a hand's width away from the alternator). Follow the vac line from the turbocharger, this goes directly to the BCS. Test the turbo and BCS in one easy step: remove the feeder vac hose that comes over the engine from its connector (seal this and photograph it so you remember where it came from). Now take the control vac hose off the turbocharger. Put the feeder vac hose directly on the turbocharger and start the car, get someone to give it a little rev (nothing over 2500rpm). You should watch the arm under the round gold widget that the feeder vac hose is now connected to.

If that arm does NOT move:

1) Check that feeder vac hose for damage or looseness. It may be losing vacuum somewhere (common).

2) Take the car for a drive and see how good the brakes work. If you have to stomp on the brakes, you have a vac leak inside the brake booster (rare, but has occurred).

3) Get a fresh piece of clean vac hose and put one end on the turbocharger. Suck on the other end (not "Stormy Daniels" style, of course) and see if the actuator moves and if it holds vacuum. The actuator may have a damaged diaphragm (has happened before).

If the arm DOES move:

1) Vacuum pump and brake booster are GOOD.\

2) BCS is likely at fault (common), BUT save yourself some time and money and check all of the other vac hoses first. I replaced mine (completely) - takes about 3m of 3mm vac hose (Supercheap sells this stuff) - and test again before giving up on the BCS.

3) Check the electrical connection to the BCS (unplug it and plug it back in to clean the contacts). Still faulty? Probably a bung BCS.

With a failed BCS you have two main choices:

1) Replace the BCS with another. Nissan want about $240 for one, but you can get Chinese replacements for around $35 on eBay and they DO work.

2) Replace the BCS with a Tillix/Dawes valve. I'm using a Tillix valve from https://www.tillix.com.au/product-category/boost-control/tillix-valves/ ($165) and never worry about it again (except for vac hoses). A little modification is needed to the turbocharger output pipe (the hard pipe before the baffle.

Sorry for the essay, but I hope I've covered it all.

Very informative reply.

 

[Chapster]

Geez @Corey d40 I cannot imagine how frustrating it would be to have already replaced the turbo, intercooler, BCS and MAP sensor only to have your boost-seeking heart still broken. It would be bittersweet to find your issue is something as potentially cheap and simple as a perished or displaced vac line or leaking brake booster but I hope that's your experience. Let us know how you go with the test Tony has mentioned above (i.e. bypass BCS and connect vac direct to turbo actuator).

A vacuum pump (even a cheapy off ebay) can be a pretty handy tool when trying to identify and locate a vacuum problem.

If vacuum is good you could turn your attention to whether the actuator on your turbo is properly calibrated, but given you have replaced the whole turbo already (yes?) you would presume this was correctly calibrated from the factory. Testing it will also require a vacuum pump if you go down that route.

I hate to say it too but you possibly cannot presume the new BCS you purchased is tickety boo (especially if you did what a lot of us here have done and purchased a cheap knock-off). Not entirely uncommon they are dead on arrival, so keep that possibility in the back of your mind while tracing your problem.

Good luck mate, keep us posted.