52 replies to this topic

[siztenboots]

On the actuator you have, can you fit a spring with less force needed to move the rod.

 

When my Courtenay actuator ( the uprated ones with the different bracket) went bad , I was getting 32psi for a couple of seconds before ECU set a fault code for P0238 Turbocharger Boost Sensor A Circuit High

 

The problem with the CS ones, is you can't take them apart and although they look like a Cosworth type , they have removed the markings and spring information.

 

I have since gone back to a standard VXR "DZ" , partly as its the most common one in use by my customers.

[james4563]

I have turbo smart actuator from Courtney I checked the spring inside yesterday and it's got a blue/brown spring which is listed on turbo smart website as 10psi spring. It seems to open around maybe a tad before 10psi so I think it's right. I did notice that it opens and then closes I couldn't get it to hold at all but I think it was because I used a foot pump. Strangely if I run with the BCS disconnected I thought I should see boost at actuator pressure?? However foot to the floor results in a max boost of 0.45 bar, and it doesn't hold it, maybe it'll hold it a second or so but I keep my foot down and the gauge just goes down to 0bar.

[james4563]

Okay an update. Resetting ECU appears to have resolved this issue. Anyone make any sense of that? Yesterday morning I pulled fuse 8 for about 15 mins, max boost I've managed since then is 1.69bar which is pretty much what Courtney said it made in their Dyno. Prior to ECU reset I was consistently getting 1.85bar in 4th gear pulls from 40mph. Torque android app was logging 33psi lol.

[Nev]

If you pulled the fuse then all you did was reset the temp tables in the ECU, over time they will likely evolve such that the boost creeps up as it did before. Unless one of the sensors you've swapped out has had an effect. Time will tell.

Edited by Nev, 23 November 2017 - 12:33 PM.

[james4563]

Well the sensors were all swapped before ECU reset and I was still seeing 1.8bar consistently when doing a pull in 4th gear from 40. Since I reset the ECU I've not seen over 1.65bar, which is the boost it was making on the Dyno when Courtney mapped it. Does anyone know if the ECU self adjusts for any old sensors. For example had it got used to slow response on one of the solenoids and was perhaps compensating for that sensor? I'm glad it's working now but it's always nice to know the cause rather than just "oh it works" 😀

[james4563]

Something stills not right. It never used to drive like this.

 

In 4th especially but it happens is all gears. It starts boosting up and right when it hits ~0.9bar it just flutters like mad. Unless I am wide open throttle then its fine. Jerks the car all over the place. Sometimes it doesn't flutter but will just loose all boost at the same point -~0.9bar.

 

Has anyone else got a stage 4 and can tell me if it's like this? Makes driving on the motorway ridiculous as it just flutters all the time and the only way to ensure it wont flutter is to just go foot to the floor. 

 

It for sure wasn't running like this when I bought it.

 

I've replaced MAF, both BCS, and actuator is set at 10psi and opening fully to the looks of it. The only sensor left is the MAP sensor, however I don't know if that would cause these issues.

[Nev]

I'd swap out the bypass valve (in the turbo compressor chassis) and MAP sensor in that order next.

 

I'd also buy + install that £5 video camera I recommended, just to prove your waste-gate is actually opening. If you are seeing very high boost (which you say you were) then it seems likely that either the waste-gate or the bypass valve is not working...

 

Also, did you carefully check the vacuum pipes to/from the 2 solenoids and black vacuum reservoir for splits/poor connection?

Edited by Nev, 28 November 2017 - 09:19 AM.

[siztenboots]

firstly I would unplug the rubber pipe at the recirc valve end , and plug the end. 

 

if the recirc is dumping the boost , then you can eliminate the wastegate side of things

 

the downside is when you come off throttle , you will lose more turbo compressor energy and will get chatter noises , if you were getting this anyway then chances are something wrong with vacuum side of things.

 

also I would not trust the boost gauge as depending on where you have connected it , you will get different readings to the ecu controlled map sensor.

[james4563]

I'm awaiting a camera to video the wastegate. I haven't tried running with DV disconnected, won't it still open though with the pipe disconnected at the DV end, once the boost pressure overcomes the DV spring?? Sorry if I've misunderstood. I have checked all of the hoses on the vacuum side multiple times, I've even zip tied the joins and tested them with a foot pump, no leaks upwards of 35psi. Unless I've missed one, is there any other pipes other than the ones that go to the vac box and rear bcs, then around to the DV and also the fpr? I've checked the pipe from turbo -> intercooler as well, but if there was a leak here is expect boost loss anyway. Does the MAP sensor tell the ECU what load the engine is under, or is that calculated some other way? Nev, I've managed to check all the pipes on the solenoids yes, can't find any leaks, splits or anything. Will try camera and see wastegate. I actually wondered if the 10 psi actuator is too strong and it needs to be weaker. Isn't the standard actuator only like 7psi?

Edited by james4563, 28 November 2017 - 10:39 AM.

[siztenboots]

there is one for the brake servo , but this has a one-way valve

 

there is another vacuum line for venting the carbon canister and fuel tank

[james4563]

Any pointers as to where they are? I guess the brake servo one is the one on the opposite side to the fpr? Bigger diameter hose with a valve, loops around behind the inlet manifold? Does the vac carbon canister t off from that? Or is there another manifold output?

[james4563]

Oh I see now there is a weird black and yellow connector, which I presume is to the brake servo and the other one that does a ubend goes to the carbon canister, can I just pull that carbon canister one off and blank the manifold to rule all that pipework out??

[Nev]

I'm not sure why you are concerned/looking at your servo vac line, it won't have anything to do with this problem you have.

 

One easy "cast iron" test to check your actuator + waste-gate are working correctly is this:

 

1. Buy a length of 3 or 4mm I/D vacuum tube, roughly 2 metres, long enough to stretch from the inlet manifold side of the engine to the turbo side.

2. Buy a 3 or 4mm I/D plastic T-piece connector.

3. Disconnect the vac pipe from the FPR, connect the new T-piece and vacuum tube you've bought, being sure to re-connect the existing vac tube to the FPR. Thus, you now have now plumbed in one end of the new tube to the inlet manifold.

4. Connect the other end of your newly plumbed in vac line directly to the nipple on the waste-gate (thus bypassing/eliminating the solenoid vac pipe on the turbo chassis).

 

To summarise, your waste-gate should now be triggered to open and close directly by inlet manifold pressure. In other words when the inlet manifold boost reaches whatever your actuator spring pressure is then the waste-gate should open and stop boost rising any further. Thus, when you now go for a test drive you're max boost should be whatever your base actuator spring pressure is (with a small margin of error due to the difference in pre & post turbine EBP (which I won't go into because it will likely confuse you)).

 

In this config, if your car is boosting up to a max of 10 PSI (or whatever your actuator spring Lb is) then you know that your actuator and waste-gate are both operating fine. Under this condition, you should experience really smooth power delivery, albeit a lot less power than your normal stage 4.

 

This test is a standard elimination test. I know it seems like a pain to you, but you just have to get on with the process of elimination and info gathering. If you find you are still getting big boost levels with this test then you know for sure that you have either a faulty actuator or faulty wastegate flap.

 

HTH.

 

 

Edited by Nev, 29 November 2017 - 09:57 AM.

[james4563]

I have tried ( again ) what you mentioned i.e connecting the actuator with bypassing the ECU boost control solenoid still seeing the same issues.

Even with the actuator set at it's weakest and boost solenoid bypassed I still saw over ~1.3bar on my boost controller and ~20 psi using the torque mobile app connected to ECU via bluetooth ODB ( I presume it uses the MAP sensor here ).

 

I also connected my boost gauge into the actuator pipe, which showed a max pressure of 0.88 bar, I figured that there must be a leak on the pipe because if I am getting 1.3 bar from the manifold the actuator signal pipe should be seeing a similar level of boost from the turbo compressor and would at that level be wide open. A Leak on actuator signal line would mean the waste gate probably wouldn't be opening fully. I cannot find a leak at all though, from the actuator or the signal line to it, if I take the hose off and use my foot pump it can hold 30psi with no signs of any leaking!

 

I have also tested my boost controller against two pumps btw so I know it is reading pretty accurate.

 

Thanks for this too:

 

 

 

[color=rgb(40,40,40);font-family:helvetica, arial, sans-serif;]which I won't go into because it will likely confuse you[/color]

 

[Nev]

The main thing that strikes me from your latest test is this:

 

Your torque mobile app can (presumably) only be getting it's boost info from the MAP sensor (0-5v) via the ODB2 connector. So if the MAP sensor is indicating 20 PSI of boost but your analogue boost gauge (plumbed into the manifold) shows only 12 PSI, one of them must be wrong as they are strongly conflicting.

 

Either your boost gauge needs replacing or your MAP sensor does. I would best guess the latter (as I suggested a couple of weeks ago), particularly is it is critical to controlling boost levels. Do try and make sure you buy a genuine one though (not a Chinese/copy one!) and swap it out. It's not a hard job, and at the very worst will eliminate it as a possible suspect.

 

 

QN: Where does your boost controller get it's info about the boost level? Is it plumbed into a manifold vac line?

Edited by Nev, 04 December 2017 - 03:20 PM.

[james4563]

I meant I had tested my boost gauge against two foot pumps which also have gauges in them, sorry. It is in fact a boost controller but I am only using it to read the boost, all boost control is done by OEM setup. I'm going to test the map sensor tonight, i will remove and put a hose on it, with a foot pump and compare the torque app reading to the pump gauge. I agree one must be wrong. I presume because the map sensor is on the cold side of the charge cooler it should read a very similar pressure to that of the boost gauge. I don't expect much pressure drop between the MAP and the throttle body. Maybe this is just the nature of the level of tune. However I don't remember it being like this when I bought it and it seems to be getting worse. One thing that I haven't mentioned which has started happening recently is that the car has stalled 3 times now while approaching a junction. When I take it out of gear the revs seem to drop very low ~500rpm.

[Nev]

Honestly for the price of a new MAP sensor, I'd just swap it out for a new one. Testing it might show it "working" but even if it is, it might be well off it's normal calibration curve (ie only partly working and sending the wrong voltage) under certain conditions. Remember it's 15+ years old and seen millions of litres of air rush past it at hundreds of MPH.

[siztenboots]

or the chargecooler has split

[james4563]

I did wonder that, but wouldn't it result in lower boost levels rather than overboost??

[Nev]

Your stalling is likely a different problem cause to the original boost problem.

 

The most likely reason for rev hunting + stalling is a leak in the pipework from MAF to inlet manifold. I have a bung and can pressurise it all up with my compressor and it finds leaks in 30 seconds.