ZD30 hard to start in the morning, Turbo outlet pipe blew off, boosting 4-7psi higher than usual

[Slappy]

Hey guys, hoping someone might have some guidance on this one.

Monday morning the car started an ran perfectly normally on the way to work and home.

The following morning it didn't want to start. It did, but was coughing and ended up stalling out. After I hand primed the filter it started with some pumping of the accelerator and ran normally into work.

On the way home the same day I started hearing a sound like an airline blowing, pulled over to have a sus and the turbo outlet pipe running across the top of the motor had blown the rubber hose off the motor. I couldn't fix it on the side of the road so I drove home gently and reattached it once I was home. I also plugged my gauges back in (I had disconnected them due to being too bright at night)

On the way into work this morning it started like ass again, needed priming etc, but drove fine for about 10 minutes before my gauges started beeping. Turns out I was boosting at 20-23psi which is up from around 16 under full load normally. All I could do this morning was let off the pedal and try to keep it around 15 thinking I'd be safe. I gave it a bit of beans a few times on the way and it seemed to settle into around 17psi, so seems to be worse if I keep it under load for a decent bit of time. I also noted in the car park coming in that in 2nd around 3-4 psi it would read 0 then back to 3-4 on and off.

Any ideas? My instinct is turbos on the way out, might be seazing and spinning too freely but I don't know enough about turbos and diesels specifically to make a call. I can't understand how turbo going out could cause the issues on start.

Is it safe to drive if I keep the boost low and I'm not hearing any awful noises from the turbo? I still need to get to work lol

 

[tweak'e]

check the waste gate. may have split the waste gate hose.

 

[dattorob]

as tweak said, also at around 22 psi an over boost protection feature will kick in and that will make feel like its surging. Check your entire air intake path that everything is tight and clamped also that your MAP sensor is plugged correctly. Believe it or not these older generation turbo's are fairly simple.

 

[Slappy]

Thanks guys,

check the waste gate. may have split the waste gate hose.

So I started tinkering around and ended up taking it to my local mechanic to put air into the actuator and they couldn't get it to budge, so stuck waste gate for sure. BUT, driving home last night it seems to have freed itself up and drove like normal again...

Plan is to fiddle about a bit more, not sure if moving the waste gate by hand might help free it up more or not but worth a shot in the interim.

as tweak said, also at around 22 psi an over boost protection feature will kick in and that will make feel like its surging. Check your entire air intake path that everything is tight and clamped also that your MAP sensor is plugged correctly. Believe it or not these older generation turbo's are fairly simple.

Interesting, I didn't know that, how's that work? I caught it at low 20s, not sure how high it got but as soon as I let off it came back down no worries. The hose that popped off, I *think* its the turbo outlet pipe, that rubber joiner looks like it could be freshened up. Any specific type I need to get?

 

[dattorob]

If you can get a silicone made replacement that would be better than the stock rubber, last longer and more pliable. In the past i have used ebay or plazmaman, basically where ever you can find.

The overboost must be picked up by the MAP sensor then fed to the ECU, where it cuts fuel or timing not sure which. I discovered it when i was tuning my fuel cut defender on my Nav ZD30 and i kept hitting like a wall at higher boost. FCD is installed inline with the MAP sensor to rescale the boost that the sensor see to avoid it hitting this cut while running the desired boost.

Be almost easier to unbolt the turbo to be able to inspect it properly and free up that wastegate , perhaps some CRC and compressed air might help free it up. But then you would need a gasket kit to re-install it.

 

[Slappy]

Yeah roger that, I'll get on the shops and see about a silicon one and some better clamps, the ones on there look like they're meant for garden hose but until now haven't caused an issue so haven't even considered swapping them out.

Say I pull the turbo and spend a bit of time smashing it with CRC etc, what are the odds it stays good anyway? I'm thinking its probably the original turbo still, wondering if I might be better off biting the bullet regardless.

 

[Slappy]

Guys the mechanic I spoke too said the top end of the fuel systems on these can often leak air into the system, presumably causing the hard start. I didn't ask enough questions to know where too look but I presume he's talking about the liftpump/fuel filter rig? Is there anywhere else I should be looking for common issues?

 

[dattorob]

these turbos are pretty robust, mine was still good at 400k km, up to you, i only upgraded mine because i wanted more power. Yeh install some clear hose after the primer/lift pump check for air bubbles.
Think i've got a list of hard start issues that i've collected from this forum some where .

e.g. from a previous post

Air in the lines P7 fault code

Danielrusty
The p7 seven code is caused in most cases by AIR in the fuel and not a stuffed injector pump (but it can be ) what happens is air mixes with the fuel the cam postion sensor in your injector pump get all confused and *****.

Do a bubble test using a a clear section of hose in between your primer/fuel filter so you can see the fuel flow once you have fitted the clear fuel line prime the system and start the car up give it a couple of minutes up to 5 to allow for all the air to get out of the fuel buy using the clear fuel line you will be able to see if there is excessive amounts of air in your fuel (there will always be some little bubbles) but if there is many more than a small amount you have you have air getting in your fuel system and causing problems if there is bubbles check the following

All fuel lines for security

Your fuel line running to your fuel filter/primer(rubber ones ) and the one running from your fuelfilter/primer to your injector pump if they are hard just replace them don't even muck around

Swap your fuelfilter /primer with a known good one they have a bad habit of sucking air in around the top where the primer is if you jiggle it and tap it you might be able to see the air while your doing your bubble test.

Even if you are happy with the bubble test i would check the other things i have listed as for the problem could be happening while you are driving under certain conditions that you will not be able to replicate at idle.

If there is a problem it will be before the injector pump like i said the fault occurs when air gets mixed with the fuel and the cam sensor in the injector pump gets all stuffed up.
and check the earths locate on the right hand side off the engine on the front corner area of the intake manifold you will see the if you remove your engine cowl there is 3 in a row.
but at the end of the day it could also be a stuffed cam sensor/injector pump
hope this helps cheers dan

 

[dattorob]

Navara D22 ZD30 – hard starting tips

- check earths are tight and not corroded

- voltage to glow plug relay

- glow plug fuse

- put clear fuel lines before/after fuel primer to check for bubbles

- ended up putting a fuel lifter pump and another filter at the tank

- starter relay

- earth that is behind the battery was dirty and loose

- clean up battery terminals

- new vacuum hoses around swirl etc

- The terminal from the fuel sender to the supply pipe was corroded, leaking slightly and letting air into the system. I noticed a small patch of diesel sitting on top of the tank around the sender.

- The non return fuel valve had failed letting fuel seep back from the supply pipe/filter when the engine was not running. This valve is located up between the tank and chassis rail.

 

[tweak'e]

Thanks guys,


So I started tinkering around and ended up taking it to my local mechanic to put air into the actuator and they couldn't get it to budge, so stuck waste gate for sure. BUT, driving home last night it seems to have freed itself up and drove like normal again...

Plan is to fiddle about a bit more, not sure if moving the waste gate by hand might help free it up more or not but worth a shot in the interim.


Interesting, I didn't know that, how's that work? I caught it at low 20s, not sure how high it got but as soon as I let off it came back down no worries. The hose that popped off, I *think* its the turbo outlet pipe, that rubber joiner looks like it could be freshened up. Any specific type I need to get?

by mem its something like 25-30 psi before it will flag a high boost error. would have to check the book on that.
the hose popping off is partly caused by the oil from the breather getting inbetween the rubber and the metal. this is why good catch cans help. make sure you degrease the pipes before putting the hose on.

 

[dattorob]

by mem its something like 25-30 psi before it will flag a high boost error. would have to check the book on that.
the hose popping off is partly caused by the oil from the breather getting inbetween the rubber and the metal. this is why good catch cans help. make sure you degrease the pipes before putting the hose on.

i didn't experience it that high according to my gauge

 

[Slappy]

I've found a fuel leak, seems to be when I'm hand priming the pump that it's wettest but still damp after a run. Down at the bottom of these hoses which I presume is the injector pump? Leaks definitely coming from the hoses, probably just the left one but I'll go ahead and replace both of these asap.

 

[dattorob]

yeh your on it, pretty sure i have had to replace that one long time ago, either return or feed to the pump

 

[Slappy]

yeh your on it, pretty sure i have had to replace that one long time ago, either return or feed to the pump

Did you just replace the rubber length and clamp? Done a bit of googling and can't work out what sort of hose I need, figure I'll just head to Sprint in the morning and grab something that says fuel and high pressure at the right diameter lol

 

[dattorob]

exactly as you say, long time ago but i think i just grabbed something from supacheap auto fuel rated /correct diameter

 

[Slappy]

exactly as you say, long time ago but i think i just grabbed something from supacheap auto fuel rated /correct diameter

Any idea on the diameter? I can't take some off to measure because I still need the car to get to work and Google isn't being all that helpful. Id have to guess its like 14mm or something

 

[dattorob]

just measure the outside diameter with some calipers on the vehicle, or use some string & measure the circumference & convert it. Hopefully the internal diameter being that it is standardized fuel hose conforms.

Circumference to Diameter Calculator