Boost/power troubles after EGR and/or new intercooler

[Hodge]

Just posting this up to see i anybody had similar problems and/or any ides what this could be ... I mentioned some of it in my diesel power intercooler write up last week so some may be familiar with my problem.
Firstly thanks a heap to Mudski for helping us out with trying different mafs and egr plates... Was over at his place for a bit last night talking s*** and throwing out ideas.

Flow of events...
Fitted up dawes and needle valve ages ago and the car ran like a million bucks after it. Then I dropped in a EGR plate. Had to wind down needle a tad, since it was spooling up a bit faster with EGR blanked. So had the car running flawlessly for about a month like this.

Then last week I installed a new diesel power re-cored and tig welded intercooler and at the same fitted up a catch can. The car ran fine for half a day or a day and then it turned to s*** ...

Basically what's happening is, it'll fly through 1st , 2nd and 3rd gear boost spooling up fine or quicker than usual and maxing out boost. Then in 4th the car begins to labour, and spooling up takes a little longer than usual. Basically, it's turbo lag. It does get there, but very slow. EGT goes sky high until boost picks up. The other thing is @ 100km/h where my cruising boost was around 10-11, now hits 17 (my max) as soon as i touch the throttle.

So the trouble is, if I wind down needle to fix 1st 2nd and 3rd, I'll make 4th much worse... If I wind it up, to fix 4th, the first 3 gears are terrible as it shoots to max boost in a second and the snail is spinning it's tits off for no gain...

The other little variable is... Up until I've installed the intercooler, I've had NO codes on the system. As soon as the IC was fitted, P0401 ( no EGR flow) code popped up. Which is common on the common rails after blanking the EGR. I'm just getting the code on scan gauge and no engine light.

Could this larger intercooler be messing with my head and just making the mid range gears and power more unstable ? Maybe the extra flow of air into the system, is somehow stuffing up the EGR valve? Also does this P0401 code do anything to the system like put car into limp mode or somethign, or is it just a warning.

I've began the process of elimination, took EGR plate off and re-fitted old gasket to see what happens to begin with. This will drop spool up rates across the board a little.

Any ides would be appreciated. The car as it is now is, not pleasant to drive. Very frustrating as I need the rig over the next few weeks to run well!

[the evil twin]

P0401 should illuminate the engine light and latch it until cleared.
If you have the code on the Scangauge and no engine light it is either an artifact on the Scangauge and the code isn't new OR something is dodgy with the ECU not latching teh check engine light.

You obviously have a problem if the EGT's are skyrocketing and it may be simply the Dawes/Needle settings but I can't help you there.
After blocking EGR I left my Turbo as ECU controlled and adjusted the VNT as per the bible and she goes gangbusters.

[boots]

The scangauge eliminates or over rides faults if you need doesn't it Hodge . ? Mate I would try a new spring in the dawes valve , reading your post suggests you've tinkered with it a fair bit so it or even the ball seat may be suspect . 17PSI max with a fresh IC may be a poofteenth too high also , some like it some don't . Hope you sort this out mate .

[Hodge]

Thanks for the posts guys!

@the evil twin
The code 100% wasn't there before intercooler/catch can install, and 110% didn't show up an engine light. Code clears with scangauge. After blocked the EGR again last night and code is gone and not returning.

@boots
I didn't touch the dawes valve much, if at all, because my max boost never changed or didn't need to, so it may not be the spring maybe. I'll try lower boost like you suggested.

Was talking to Mudski again, and I'll re-setup the valves a slightly different way to see if it helps anyway. If not I'll have to start looking at other things. Another thing I noticed it runs ok-ish when cool, like morning and within 10-15 minutes it starts to go a tad sluggish so... Anything is possible right now.
One of the things I'm worried about is the day before it began doing this, I was due for a tank fill and the main tank was below quarter so, it may have maybe picked up crap of the bottom of tank. So fuel filter is next on the check list if boost system doesn't help. Either way it's not running too smoothly at the moment so, watch this space.

[Hodge]

Just re-designed the dawes/needle setup, and I'm not 100% but it may have improved a little. Will test out tomorrow. Fingers crossed.

[Hodge]

Just thought I'd update this.
After re-shuffling some of the boost control vacuum hoses and re-doing the dawes/needle setup the car now hammers again.
Thanks to mudski for pointing this out.

[threedogs]

over a period of a few months I fiddled with the dawes
and needle until I found a happy spot goes like its stolen now lol

[Hodge]

over a period of a few months I fiddled with the dawes
and needle until I found a happy spot goes like its stolen now lol

Well I had that sweet spot until I slotted in the new IC. The car went so good, I didn't want to touch anything else in case I lose it. And lose it I did, with the new IC... But now it's all about tuning it to that sweet spot again. I also re-newed some factory hoses which I reused in the setup. So it may also have been some of those hoses leaking or blocked.

[threedogs]

can you put up some EGT readings later for 100kph , 60kph etc If possible
Would like to compare to to an OE tigged unit

[boots]

So is the egr blocked or not Hodge

[Hodge]

So is the egr blocked or not Hodge

Nope mate it isn't. I took the plate out when I began getting this issue, and as I mentioned above at the same time I started getting the EGR code. Maybe was just a co-incidence.
Removed the EGR blank, code is gone, but it didn't fix my problem. Cars back to normal only after fiddling with the dawes/needle setup.
I got another blank from Mudksi with a hole in it, so I'll drop that in this weekend, and see what happens.

[threedogs]

Don't others drill a 10mm hole in the EGR plate to stop the ECU on
the CRD from throwing up error codes all the time

[Hodge]

Don't others drill a 10mm hole in the EGR plate to stop the ECU on
the CRD from throwing up error codes all the time

Yup. I could have done that too. But I got another plate off mudski with a hole already there, so I don't have to destroy a perfectly good plate, which somebody else can use.
I'm a bit sceptical of the plate with a hole though. I mean you're blocking the EGR but yet opening a hole for it. Surely that hole will eventually cog up with crap anyway ?
Anyhow will give that a go.

[threedogs]

Its only purpose is to trick the ECU into thinking the EGR is unblocked,
maybe periodical cleaning might be required as part of your maintenance .

[Hodge]

Its only purpose is to trick the ECU into thinking the EGR is unblocked,
maybe periodical cleaning might be required as part of your maintenance .

Yeh it's meant to equalize pressure on both sides of the plate fooling the sensor, while still trying to block the EGR flowing through. I'll fit it this weekend and see what happens.
Pain in the rear end to do on the CRD, so I don't want to do it too many times.

You asked about the temps after the IC. Well cruising at 60 on flat roads it sits 250-300. At 100 its about 300-350. Even a slight hill, pushes it past that. Since fitting the dawes and needle valve it has dramatically improved my EGT's. I used to see 500-550 without much effort, ever since then I'm yet to see it go past 400.
New IC dropped my cruising temperatures, and reduced the turbo cool down time. Should also mention that while my EGR was fully blocked, the EGT temps were much lower too.

[mudski]

Great to see it's sorted Eric. Sorry I didn't respond to your text but it's just crazy with work and I just plain forgot to respond.
As for the egr plate. I would put the solid plate in, if you haven't already done so...

[Hodge]

No stress at all buddy, totally understandable. Flat out with work here my self, couldn't spare a daylight hour to put the plate back in, but will definitely do so.
But shes going like it's stolen now. Which is a great outcome. Thanks again for all the advice and the MAF's and plates.

[barbz]

Did you old IC have holes in it leaking boost?

If so did you notice if spool rates in 4th and 5th while better than where they are now still slower than gears 1/2/3?

[Drew]

I get the EGR code popping up every month or so. Scangauge fixes that. I'm certainly not taking it out and drilling a hole in it now.

Just so you don't think you're going silly Hodge, I have had the code reported in the scangauge but no engine light as well once (that I know of).

[Hodge]

Did you old IC have holes in it leaking boost?

If so did you notice if spool rates in 4th and 5th while better than where they are now still slower than gears 1/2/3?

My factory IC had a tiny leak which only became apparent after I installed the dawes / needle valve. Obviously this put more boost through the system, and finally weakest point of the crimped IC gave way.

And yes after the new IC, 4th and 5th definitely changed and lagged in spool up rate.


I get the EGR code popping up every month or so. Scangauge fixes that. I'm certainly not taking it out and drilling a hole in it now.

Just so you don't think you're going silly Hodge, I have had the code reported in the scangauge but no engine light as well once (that I know of).

Thanks Drew. Good to see I'm not the only one. The fact it wasn't throwing an engine light, sort of concerned me, since a lot of other people had it pop up as soon as they got the code. I'll be putting the full blank back in.

[Drew]

My engine light went out a couple of days ago and I didn't even clear the code.

Maybe there's a "I've tried telling you but noooo you won't listen" timeout :)

[Hodge]

My engine light went out a couple of days ago and I didn't even clear the code.

Maybe there's a "I've tried telling you but noooo you won't listen" timeout :)

Haha interesting that one. Maybe mine will be the opposite, for a while no engine light and then it'll start screaming at me .

[Hodge]

Bringing this back up on a negative note...
This issue has not gone away, as the car is still an absolute slug sometimes, and I really do not know what steps to take next or what else to look at.
So to summarize again...
At the moment, the car is 50/50. Half the time is has plenty of go across all gears, across all speeds. Sometimes when I have to put a bit of boot in to over take or something, I'm amazed how much grunt it can have when it wants to. Very responsive acceleration/pedal.
Unfortunately the other half the time, the car is a cooking slug. An example, on the ring road today, flat road, sitting at 80km/h in 4th or 5th it doesn't matter... Put the boot in and she just sits there labouring/cooking away. EGT's start rising, the car very slowly gaining momentum... The turbo though at that moment is already peaking max boost?! But, a day earlier, the same instance the car would have had all the power in the world. Just doesn't make sense.

I know my turbo is most likely shot, as it has a mechanical winding noise. I opened the passenger window today, and turned the snorkel head towards the windows and it was pretty evident something isn't right in the snail. However, I'm unsure if this is the culprit?! Is it possible to have max boost, turbo spools up quick and yet no power? The fact the EGT's are rising means fuel is being pumped in so, I'll assume issue isn't on the fuel side?

I have tried everything. New MAF's, fiddling with the needle and dawes valves to no end. Annoyed mudski to hell and back adjusting and fine tuning it and still no go... Changed air filters, fuel filters, new intercooler, EGR blocked or not blocked... Makes fark all difference.
Nissan has had a look, but to them if there is no codes, then there is no problem. Had a mates mechanic have a look too and he says he cannot find nothing. Although I dont know how much hes actually looked.

To say I'm pissed off is, an understatement. I'm rapidly losing faith in these CRD's.
Anyways thats my whinge for the evening.

[mudski]

What's the word about your turbo? Is it fubar or not? Sort this out first I reckon. As I have been in the passenger seat with you mate, I have seen how you drive the car. To be honest mate. Rev that car a bit harder and draw out the gears more. I had the impression that you weren't driving in the Rev range mate. These motors really don't like to be under the Rev range. But it could be your turbo playing silly buggers mate, I dunno...
I'd be interested to hear more about the turbo though.

[Jamiepatrol]

Hi hoge. i had similar woes on my 2010 crd, which is now written off. nissan thought it was the pedal, which was replaced under warranty?
have you followed proper dawes and needle setup by chazz? thats the guide i used and it seemed to make my car a tad more responsive?
there is a place in bundoora i believe, turbo engineering, assuming youre still in thomastown, maybe they can suss your turbo out???

[Hodge]

@ Mudski
Understand what you're saying mate, these things like to be revved. This problem I'm having isn't that. In 4th, it's sitting at 3000rpm, turbo going full chat, sitting at around 80-85, I'm well into the power band range, pedal to the floor and she goes nowhere still. At this stage the turbo/boost is already maxed, 17psi. 5th gear is even worse. It just seems like turbo runs out of play, it's already spinning it's gaskets off and just can't push any further.
And once again, another time, identical scenario, and she will be a rocket...

I'm curious though, aim of the boost setup is to have roughly 10 psi at 100km/h? Is this on a flat road? Cruising?

As for the turbo, I'll go to JPC, see what mark says. Can't think of any other good local place for this. He initially diagnosed it as a mechanical noise about a year ago. Unsure what a turbo replacement will sting me, like for like.



Hi hoge. i had similar woes on my 2010 crd, which is now written off. nissan thought it was the pedal, which was replaced under warranty?
have you followed proper dawes and needle setup by chazz? thats the guide i used and it seemed to make my car a tad more responsive?
there is a place in bundoora i believe, turbo engineering, assuming youre still in thomastown, maybe they can suss your turbo out???

Hey mate. The only thing that place is good at engineering, is your bank accounts into negative, very quickly. My pedal was replaced under warranty, and this didn't make any difference, it wasn't worse or better.

[threedogs]

here's one for you ,,,,swap the ECM relay with the Air con relay to eliminate that,
the relay could be failing intermittently, don't forget a poor earth, maybe run some new ones
but swap over those relays and try it.

Turbo Engineering know their stuff, good place to get it Dynoed

[Hodge]

here's one for you ,,,,swap the ECM relay with the Air con relay to eliminate that,
the relay could be failing intermittently, don't forget a poor earth

Turbo Engineering know their stuff, good place to get it Dynoed

Hey TD. Thanks mate. What exactly does that do? Are the relays identical? I'm thinking if it were a relay, wouldn't the ECU cut out completely at some stage, therefore the whole engine would stop? I've checked earths, but will do again.

As for the turbo engineering, you are the first bloke to say a good thing about that joint.

[threedogs]

don't know him and have only heard good from his Dyno work.
I believe the relays are the same for the sake of testing. If it intermittent
it may have symptoms like you describe,
I'm thinking of the easy things first, Yendor suggested this to someone else a while ago now
Its just one less thing to check, only do one thing at a time then you'll know what it is.

[mudski]

I'd rather crush my left nut in a vice than take my car to Turbo engineering... JPC any day of the week...
TD needs to start taking his meds again I think...lol.

[mudski]

@ Mudski
Understand what you're saying mate, these things like to be revved. This problem I'm having isn't that. In 4th, it's sitting at 3000rpm, turbo going full chat, sitting at around 80-85, I'm well into the power band range, pedal to the floor and she goes nowhere still. At this stage the turbo/boost is already maxed, 17psi. 5th gear is even worse. It just seems like turbo runs out of play, it's already spinning it's gaskets off and just can't push any further.
And once again, another time, identical scenario, and she will be a rocket...

I'm curious though, aim of the boost setup is to have roughly 10 psi at 100km/h? Is this on a flat road? Cruising?



Cruising on the hwy mate in 5th....

so is the turbo stuffed or not?

[Hodge]

Cruising on the hwy mate in 5th....

so is the turbo stuffed or not?

Turbo is rooted. I'm 99% sure. Listening to it through the snorkle it's making rackety, loose change noise ... Just haven't had a chance to take it to the mechanic yet.

[Paule]

Just reading your post, and was thinking about your power prob, if you are already at max boost (17 psi) makes me think it's not your turbo. Just a thought mate and I'm no expert that's for sure. Is it blowing smoke when you've got the boot in it?

[Hodge]

Just reading your post, and was thinking about your power prob, if you are already at max boost (17 psi) makes me think it's not your turbo. Just a thought mate and I'm no expert that's for sure. Is it blowing smoke when you've got the boot in it?

No smoke at all, as far as I can tell. My turbo is stuffed I know that. Whether it is the cause of my power issues, is another story. I could have a rooted turbo, and another problem, which is more than likely.

[mudski]

Well if the turbo has been confirmed as stuffed. I'd be changing this and then come back to this issue. If it still exists after a turbo change...

[Paule]

Yeah I agree with mudski, if turbo bloke has told you that it's stuffed then I would be changing it. You don't want to be creating other issues.

[Paule]

I'd rather crush my left nut in a vice than take my car to Turbo engineering... JPC any day of the week...
TD needs to start taking his meds again I think...lol.

Hahahaha would you do the vice up quickly or slowly. That quote cracked me up

[mudski]

Which ever way mate it would be bloody painfull. Not as painful as the bill though...

[Rumcajs]

I wonder if that noise you are hearing is actually turbo noise and I'd like to know how did the turbo specialist determined it to be stuffed? Did he take the intake pipe/hose off and checked the compressor wheel for damage, checked axial clearance of the shaft/turbine?

Also what happens when you disconnect vac control so the turbo vanes are backed off, does the noise persist or is it gone? Is it possible you have a intermittent vacuum leak hence the turbo control can suffer?

Proper diagnosis require some spanner time not just listening to the thing unless it is so loud that it is obvious.

If the turbo is damaged check the seal under the air cleaner lid as that one deteriorates over the time, dust can get in past the filter and grind away the compressor wheel over the period of time.

This inconsistency suggest there is more to it than just one thing.

CrD ZD30 uses both MAF and MAP sensors to calculate fuel quantities, so are those values read correctly by the ECU? Also low fuel rail pressure can be indicating some issue.

Do you have access to Scangauge or cheap OBDII adapter? You can than read the sensor values and see for yourself what changes when it works and when not?

Don't discount the typical electronics "wrong input=wrong output". OBDII scanners are invaluable when diagnosing intermittent issues, the ones with data logging capabilities are even better.

Because your issue seems to be so intermittent I'd tend to think towards electronic/electrical gremlins not mechanical stuff which is more or less consistent when it fails.

CrD units have also a lot of problems with bad earthing so extra earth lead between the body and chassis is very beneficial.

Cheers

[nipagu7]

just random thoughts and clutching at straws here , but is your car manual or auto . my gu7 is manual and at 100kph in 4th it sits around 3000 rpm with standard tyres . if your tyres are a larger diameter this would be a slightly lower rpm . if you car is manual and is only doing about 85kph at 3000 rpm then i would think that you would have a clutch problem ? possibly the other problem you are sensing ?

[Hodge]

Ok, been away from here a few days now. Hence no replies from me...
Car is booked at a mechanic next week, so he will be running it on a dyno for a bit and see what's happening. I'm bloody happy but pissed off at the same time. I'm happy cause, the car has been running flawlessly last 4-5 days. It's been a rocket! But I'm pissed off that it's been "good", when I took it to the mechanic. It's like going to a dentist with a toothache, and on the way there it completely goes away like nothing happened. It s**** me!

While the car has been running fine lately, it has a different exhaust tone to it. It's like the tone changes when you open and close the needle valve (vanes) of the turbo. It just sounds different, and somewhat has a deeper tone to it? When last Mudski helped me set the valves up, he looked for a specific exhaust note for a rough needle setting. So, some pondering may suggest it's got something to do with the vaccum system slipping? Because the exhaust tone changed when the actually started behaving better ?

Was also talking to the mechanic , about gutting the vaccum system completely, and go for the wastegate setup, as well as a fully tuned chip that he does. He reckons it blows anything else out of the water and the CRD's respons really well. And this bloke knows what hes talking about. So will see how that goes... Obviously all pending what and if he finds with my intermittent power.

@Rumcajs

A lot of valid points there mate.
To answer your turbo question... Something is definitely going on inside the snail. Rattly kind of noise. It is in perfect sync with the turbo spool up/whistle. Very evident when you listen to it through the snorkle. No matter at what setting of the vanes, or vaccum completely disconnected, it makes this sound as it spools up. Once again the mechanic whos seeing it next week will suss it out, but HE personally thinks turbo is fine, even with the noise, since it is after all producing good power sometimes.


Watch this space.

[threedogs]

Guest 4x4 in Fairfield will turn your vacuum turbo into a wastegate style for around $700
less as you already have gauges, Give David,Mick or Peter a buzz

[Hodge]

Well got the car back. Good results. Long story short. He had it on dyno and road tested for a while. Replicated the power loss I had, it had consistency with a limp mode, so we put it down to that. Spent a good amount of time with the dyno guy, and he showed me something I didnt' know. CRD's by default calculate limp mode from a few different variables, like fuel, air as well as boost. It is not only a boost threshold that ticks the limp mode box. For some reason my car ticked all those boxes very often, hence my power loss experience. Anyways... Chip fixed this, one way or another.

Unichip was fitted and programmed from scratch to the car, and the power loss gone away. She goes way better now. Made 100kw at rear wheels, but backed it down a tad afterwards after clipping some high end, for safer EGT's. Wastegate setup was shelved too, as this chip also controls the boost, so for now the needle and dawes are gone as wlel. Chip does a good job at boost, much better than factory setup, however there is some spikes once in a while, which needed to be ironed out. I'll have a go at needle/dawes with the chip now to see if I can smooth it all out. Early days yet. But so far I'm happy.

48593

[mudski]

Good to see Eric. So the turbo is not fubar?

[Stropp]

That's good news mate, let's hope you can iron out the remaining small bugs.

[boots]

I hope its happy trucking for you now Hodge , my goodness you have had some pain and suffering along the way and hopefully its all sorted now.

[Hodge]

Good to see Eric. So the turbo is not fubar?

Yeah Mark thinks it's fine and should be the least of my worries for now. So I'll leave it at that.


That's good news mate, let's hope you can iron out the remaining small bugs.

Yeah good news finally, just a tad more fine tuning and she should be ok, I hope.


I hope its happy trucking for you now Hodge , my goodness you have had some pain and suffering along the way and hopefully its all sorted now.

Thanks mate. This chip and dyno as where I'm drawing the line in the sand though. I'm now sort of feeling where Jonothan's frustration was with his car, to the point where it was taking a toll on me and the mrs. I finally drove a common rail the other day, heavier than my one, but with no performance mods. Not even the manual boost setup and it went harder than mine by a long shot. Nearly made me cry ...
So if this process I'm going through now doesn't help, Patrol is gone. I really don't have any more patience, time and $ babying a car just for it to run properly. But I hope it don't get to that.


Needs to go back on the dyno, as there is a few more quirks regarding boost etc.. Especially @90km/h plus. This is the first chip of this model JPC has done on a common rail as it has a few extra things, so my car is kind of like a learning curve guinea pig for them. As I said, she has a heap of power now, down low across most gears, but just needs to be harnessed and spread out a bit and she should be sweet.

[Hodge]

Just curious...

Is there anyone here that has a chip which has control of turbo boost, yet you still by passed that with needle and Dawes ??

Sent from my SM-G900I using Forum Runner

[mudski]

Just curious...

Is there anyone here that has a chip which has control of turbo boost, yet you still by passed that with needle and Dawes ??

Sent from my SM-G900I using Forum Runner

I think the Diesel Smart chip does. Don't quote me on it but I think it does. I don't know how good it works though...

[Hodge]

Well the car was on the Dyno last 2 days again, and the Chip controlling boost was ditched for a waste gate actuator setup. Needles to say, it runs like a dream now. Heap more power and torque wastegate locked to 18psi, and is very consistent throughout the gears and rev range. Very happy so far!

[Hodge]

Wastegate actuator fitted.
48646

[Hodge]

Wastegate actuator fitted.
48647

[Rumcajs]

Well the car was on the Dyno last 2 days again, and the Chip controlling boost was ditched for a waste gate actuator setup. Needles to say, it runs like a dream now. Heap more power and torque wastegate locked to 18psi, and is very consistent throughout the gears and rev range. Very happy so far!

So how does it work exactly? Spring in the actuator loads the turbo vanes at max and once turbo pressure goes over 18 psi it starts pushing the actuator down to back the vanes off?

How does reinventing the wheel sound?

You could do the same with just the Dawes valve set to bleed vacuum at 18 psi, closing needle valve fully or ditching it completely.

B/R

[Hodge]

It's supposedly an actuator with a dawes built in, kind of. I don't know why they opted this over the needle/dawes, but I can tell you now, the car is much better with this, than it ever was with needle/dawes, no matter how much I fine tuned it.
I've just driven the car for about 2 hours after job was done , and it is the best its ever been since ive obtained it. Thats what matters to me.

[Steve4wdin]

I think the Diesel Smart chip does. Don't quote me on it but I think it does. I don't know how good it works though...

That was how my setup was. After fitting the dawes and needle you sent up, no more issues. Bypassing sensors is ok, but you need to reconfigure the ecu.