20psi boost is that to high?

gooday to all..my08 CRTD IS BOOSTING 2Opsi under load is that to much for this engine..i know the question is a little vague but if u can help me out with an answer would be appreciated or if u need more info. let me know. cheers xcape08

Gday mate,

have you fitted a Dawes valve? have you set the boost to 20?

Seems too high? have you got a Pyro gauge? what are you temps like? why have you boosted it up so high? Has it ever been dyno'd? is the fuel set up to suit the 20psi?

not really mate they can see figures anywhere from 16-22psi the CRD's seem to hae all the issues solved now

when i first bought the Patrol new, i had problems with burning a lot of fuel,a lot of black smoke rear end,had it dyno'd fuel ratio was way out,only way to try and solve it was by having more boost and air flow,ratio of fuel to air did decrease but still,blowing some smoke under load.i do have a EGT gauge and temps. under load are reaching about 500-550 C.normal driving around 200-400 C.when the Patrol was only 14months old i had to have the exhaust manifold done due to warping(heat to much fuel).Nissan Australia didnt want to know anything about it.just recently i had to have the EGR valve replaced,couldnt be repaired again, cause heat or to much fuel. Last week i found out the exhaust manifold has warped again and the turbo has a slight oil leak.I have sent al this info to Nissan Australia through a Nissan dealership and im waiting for a reply tomorrow,even though its out of warranty,the do provide a good will warranty,fingers crossed they will come to the party,the are aware of the cars history.So the reason why its at 20 psi..was to try and level out the fuel/air ratio,but im concerned wether this is causing other problems. the patrol does have gas as well(.injected).
thanks for answering my thread but if uve got anymore info ill be much appreciated ur thoughts.

hi MudRunner thanks for ur reply,i did reply with more answer to ur questions,if u can give me some more feedback that would be great

Hmmmm... Mate i am certainly no expert on the CRD 3.0 engine but what you have written about your car would indicate that there is a fault i would have though that Nissan Australia should Own. If your Dyno Tuner had to bump up the Boost to 20 to even out the fuel /air ration from a factory setup surely that cant be right and surely that cant be your fault?? If anything Nissan Australia should have been looking early at why that was needed?

Push them hard mate. Has it been doing that only since the Gas went on? that will be their out i reckon?

Anyone else with any ideas?

hi MudRunner...no the patrol was blowing black smoke when it was stock standard.i was getting egt temps under load and towing of nearly 700-800C..when the car was only 18months old i had to have the exhaust manifold done under warranty because it warped. i used to complain all the time to the Dealer didnt want to know about it.they kept saying it was in Nissans tolerance...blah..blah blah..so thats when i had to look at other alternatives to get the ratio right. the gas injection has never been an issue, i dont run it most of the time.

While CrD ZD30 can run at higher boost than previous Di and for sure can run hotter EGTs (up to 700°) something is amiss if a tuner needs to compensate with increased boost for what appears to be too much fuel being injected. (black smoke) How's fuel consumption?
Also I'd like to know how did the tuner raise boost to 20 psi. As far as I know engine ECU is fully in control of boost, it also uses EGR to control it as well. So e.g. if one blocks egr than boost levels are much higher.
Few things spring to mind, is VNT turbo working correctly and just in case that trim codes for injectors stored in the engine ECU are correct?
Cheers

hi Rumcajs...the tuner got by the ECU by bypassing the airflow meter..electronically, it tricks the ECU,so it allows more are flow,he also put in a VNT valve to get the higher boost.The code injectors is what if been trying to find out from Nissan,if its correct and set right...but again it falls on deaf ears,they keep saying its within the limits.Fuel comp. isnt great but its better than what it used to be. The EGR isnt blocked, but i did have to replace it with a new one only 2 weeks ago because it was shot,full of soot and the trap door was shut closed,Nissan couldnt tell me what could of caused it.
it is a problem ive been trying to solve for a long time, but cant seem to get the right answer.
anymore suggestion please pass them on. Cheers

Injector trim codes are stamped on the housing/body of the injector and the codes are entered as parameters in the ECU for each and must be correct for every cylinder. So either take it to Bosch fuel injection service joint and ask them if they're able to confirm the settings for each injector or take it to those idiots from Nissan to do this simple check and insist they do it in front of you.
I'm afraid the changes your tuner had done will now make it much harder to track down the real cause of what seems like over fueling.
Remember upping the boost and airflow values causes more fuel to be injected so if fuel metering is incorrect/suspect for example (let say that injector/s are leaking/ trim codes are incorrect) black smoke is evident.
Cheers

Edit: I was thinking about this a bit more I'm wondering what is the rest of the exhaust like if the exhaust manifold is warping from the heat. I'd be checking if the cat is also not partially blocked from all that exhaust soot. Also Nissan had some issues with some CrD model had no trim codes entered in the engine ECU.

Thanks Rumcaj..for ur advice,ill get the codes looked at and the cat checked as well. the patrol was blowing black smoke well before the tuner done any work on it, from day one when i brought it.
Its at a Nissan dealer at the moment getting the exhaust manifold done again(second time in 31/2 yrs the trucks only done 103000km).
They also said that the turbo has a slight oil leek as well, do u have any clue what might cause that to happen?
Look forward to any other feedback u can give me, very much appreciated.Cheers Eric

I have Dawes Valve fitted set 18psi and a boost gauge. The Maxium boost it gets to is 14psi, generallt running at 10-12psi, so i think 20psi a bit high

cheers

fred

thanks Fred for ur reply...cool..im going to look at resetting the value a little lower

Turbo has a "slight oil leak" is very broad description of a problem. Where is that leak? On the inlet (compressor side) or on the exhaust side (turbine) I wouldn't be surprised if the oil leak the morons are talking about is from all the oil mist turbo sucks from the crankcase breather thanks to unfriendly design (read Nissan/Toyo/Mitsu are too cheap to include oil separator) so there is a lot of oil in the intake itself which turbo than spreads through entire induction system. So fitting a oil catch can in the so called closed crankcase ventilation in the turbo charged engine is a must! What also doesn't help is that ZD30 sump is filled to the brim with oil once again because Nissan was too cheap to re-design the oil pan/sump (read making it bigger capacity) when they had early ZD30 genading because sump capacity and engine requirement for oil volume didn't add up among other design flaws
Research "catch can" e.g. Provent 200. That should be number one mod on any ZD 30 powered Patrols indeed on any turbodiesel having CCV and not having effective separator.
Cheers

Hi Rumcajs..not a 100% sure but 99% sure its on the turbine side,well thats what they told me over the phone,,they wanted to replace the turbo there and then, im going to the dealer in the morning to find out what actually where and how bad it is,like u said it might be nothing,most conversation has been over the phone with them.the patrol has got a catch can put on it. but again thats more info for me to work with and i appreciate it. Cheers Eric

How did you go today? Are they fixing it this time or just replacing failed parts again?
Cheers

LOL..good one,i didnt get a call from them, so i presume they hadnt finished replacing failed parts..smiles..but i will keep u posted on the out come.
Rumcaj if u have any suggestions, on someone i can take my patrol to and knows what there doing, let me know.When i do get my truck back i was going to take it to a Bosch Diesel Dealer at Regency Park,get it all looked at.
Cheers mate Eric

So you are in Adelaide than....which Nissan dealer is your Patrol at? The Bosch agent is MTQ at Opala st Regency Park I suppose they're alright I've only dealt with them through work(heavy trucks diesel fuel systems) so I wouldn't know what they like in small stuff.
Whatever you do, don't take Patrol to HiTech Diesel on Churchill rd at Kilburn, not having very positive experience with them in the past, again mainly through work.
Cheers

I’ve done my exhaust manifold and needed machining, from what i was told by Nissan and read on forums it’s not that uncommon mine went out around 30,000km due to overheating up the Toowoomba range with a loaded trol and towing a overloaded trailer.

hi Rumcajs..my patrol is at Bridgewater nissan..im going to try MTQ..give them the run down and see what they say..ill keep u informed..by the way the tuner i used was AUTOSPORTS ENGINEERING OFF SOUTH RD..they did there best to try and solve the issue, with the boost increase and by passing the factory set airflow.im going to also bring it back to them to decrease the boost a little and see what the think of the turbo leak, they also put in the catch can...Cheers Eric

Hi megatexture..Nissan have told me that as well its a common issue, theres a reason why it happens and thats where the conversation with them finishes, i was told its a heat issue which means to much fuel,and thats what im trying to solve,this is my second time its had to be machined in 100000k,u cant keep doing that.ill be posting more info as i get it. Cheers thanks for u reply

Got my patrol back,they fixed the exhaust manifold,the slight oil leak in turbo,they think it could of been the catch can going back into turbo.I took it back to the guy who installed it,he thinks it could of been the catch can as well,keeping an eye on it.
Cheers Eric

What sort of catch can/oil separator is it?
Cheers

Its a custom made one by ASE,couldnt fit a market one, not enough room under the bonnet,but ASE are working on a new design for the 3lt crtd..The guy down there said ur always going to get a little oil in the turbo,impossible to stop all of it.
but my next know is to get the injectors looked at...ill keep in touch...Cheers Eric

Hey Mate

Had a quick read though all of this to answer your first question 20psi of boost is not to high crd engines can run crazy amounts of boost without doing any damage to them. they are not like a petrol engine. If you run them up to 22psi you will hit limp mode as the airflow meter will see to much air. But as someone else suggested it will keep tipping fuel into as it sees more boost so it might not be the best of ideas. Patrols run extremely rich from factory so it's not uncommon to see them reach such high temperatures especially when under tow. The problem is they are designed for higher octane diesel which we do not have in Australia so from factory they have crazy diesel rattle and as you said, blow smoke and excessive egt's as a result. There are a few things you can do to fix it, one is up the boost which you've done, make sure the injectors are programmed correctly which you're doing so will be interesting to see the results.

when you notice such high egt's is it when the car is under load? have you tried dropping it back a gear? and do you have an aftermarket exhaust fitted to it?

Gooday Dieselsmart thanks for reading and replying to my thread....yes the high EGTs is mainly underload, i had a Tiapan 3inch exhaust fitted after 6months old the patrol.The guys at ASE in adelaide had to put the boost that high to get the fuel ratio right really had no choice..to try and get temps down.
to have the exhaust manifold go twice in 100000kms, is annoying and to have the EGR valve replaced as well..just full of soot.my last resort is the the injectors get them checked...and my last final resort is ...buy a TOYOTA...grins....jking
ill let the forum know whats happens...Cheers

Hey xcape

look forwad to hearing the results of getting your injectors checked :)

no worries..keep u informed...cheers

Hi mate, not sure on your setup regarding the exhaust manifold but is yours a cast iron mold? These are less prone to cracking however do hold the heat more which means the boost can kick in during the earlier rev range. Know a fella who briefly ran his turbo at 35 psi until he drained all the oil from the sump lol but he swears by the cast iron mold for reliability. Just food for thought.

cheers

gooday Hippo..im not sure about the exhaust manifold what its made from..its still the original from factory...it didnt actually crack..it warped due to the heat. cheers and thanks for the reply

Most if not all mass produced engines have exhaust manifold made from cast iron, Nissan's ZD30 included, cheap to make, good heat resistance.
Cheers

Hi Rumcajs...i see...ok thanks...

another question for u Rumcajs.(or Forum)...running 20psi my turbo is making a loud whistling noise at around 2000-2500 rpms..the guy how in creased the boost says that the turbo is just freer that why the noise....whats ur opinion ?...cheers Eric

Quote:

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Originally Posted by xcape08

another question for u Rumcajs.(or Forum)...running 20psi my turbo is making a loud whistling noise at around 2000-2500 rpms..the guy how in creased the boost says that the turbo is just freer that why the noise....whats ur opinion ?...cheers Eric

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if your not happy with 20psi bring it back to 16 /18 psi or lower 14 then see how it runs

turbos are meant to whistle, that noise is fine. it won't hurt your turbo.. we have set up nissan patrols running 24psi of boost that have towed vans around australia. 20psi is safe with that turbo. if you are worried about it, bring it back down a little but you will lose economy by bringing your boost down and some power.

While turbo can certainly make a noise, chances are that if you can hear it that loud you have a problem. I wouldn't be surprised that either because the exhaust manifold was off/ fixed the installation got f-ed up so there are loose exhaust bolts somewhere on the dump flange/pipe/gaskets missing/blown off perhaps or even worse manifold bolts loose or gasket blown. Wouldn't be discounting a boost leak either.
Am I understanding you correctly, is this noise happening now after the recent repairs or only since the tuner bumped the boost up?
I have straight through 3" exhaust and still can't hear my turbo whistling at 18 psi. If everything is fitted and sealed properly you will only hear a faint spool up noise at best. So if it is a loud high pitch noise under load than you have either exhaust leak or possibly boost leak from loose hose, hole in the inter-cooler or else. If you didn't hear it before and now you can than .......you be the judge.

Hi Rumcajs....its been happening even before i had issues with the manifold warping,it been happening as soon as i got the boost changed to 20psi...but ill get them to go through it all again, i need to bring it back to Nissan to check the work they did on the exhaust manifold.
thanks again mate for ur reply..ill keep u informed

I'm actually wondering if the EGR pipe is not cracked, apparently it is a common thing on CrD Patrols as well.
Cheers