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I have new clamps everywhere, including the beefy larger T clamps from the Turbo outlet to the IC inlets:
Am I right in thinking that the wastegates are closed by default, and then are held closed with the boost control solenoid? If there is a vac leak from this solenoid or its not working, what is the default wastegate pressure?
Any idea where to look next?
Last edited by alexanderfoti; Mar 24, 2017 at 07:15 AM.
If I clamp the boost line that comes from the Intercooler, I saw 18psi once, then it went into limp mode. Erased the codes and then only saw 10psi.
I removed the clamp and back to 15...... Wonder what that means? Thinking about it, I wonder if the ECU pulled open the divert valves to bleed the boost.
Last edited by alexanderfoti; Mar 24, 2017 at 10:22 AM.
Got Xentry on it, was an over boost code, so the turbos are making OK pressure and there aren't any boost leaks.
Additionally, the pipework to and from both the Divert actuator and the boost solenoid seem to be intact with no breaks. This must also rule out weak diverter valves.
All 4 MAP sensors are the correct ones and in the right place too. Air filters are new.
Off for a dyno on Tuesday with boost tied in as well so will be interesting to see if its 15psi is by design or if its low (I think its low)
Last edited by alexanderfoti; Mar 24, 2017 at 02:45 PM.
For a 65 car you should see over 20psi at times, the fact that it slowly builds as rpms climb makes me think you have a wastegate not closing. You should have full boost at 3k, and it tapers off with rpms as the turbos simply can't keep up with the airflow demands.
For a 65 car you should see over 20psi at times, the fact that it slowly builds as rpms climb makes me think you have a wastegate not closing. You should have full boost at 3k, and it tapers off with rpms as the turbos simply can't keep up with the airflow demands.
I feel like its being told to to do that by the boost control valve. Pinching the line to the boost pressure control solenoid keeps the wastegates shut, which should make max boost all the time (or at least wastegate spring pressure, which I cant find). It seems to do that under testing.
Last edited by alexanderfoti; Mar 24, 2017 at 05:44 PM.
So on my S65 I am experiencing the same thing. During data-logging I am only seeing 1960-1980 hPa. I have no boost leaks and replaced the boost control solenoid ( under driver intercooler) I am starting to thinking the data logging method isn't giving me the correct results( i am using a icarsoft i980 for data logging.) Where were you getting the reading of 15psi from? and then when you went to the dyne the car was make 20+?
So on my S65 I am experiencing the same thing. During data-logging I am only seeing 1960-1980 hPa. I have no boost leaks and replaced the boost control solenoid ( under driver intercooler) I am starting to thinking the data logging method isn't giving me the correct results( i am using a icarsoft i980 for data logging.) Where were you getting the reading of 15psi from? and then when you went to the dyne the car was make 20+?
The data logging was done via OBD with Torque and also via the dyno operator. Both via OBD. I have not verified the actual boost pressure being produced with a meter connected directly to the system.
If you check the dyno graph, the purple line is boost pressure. It immediately makes 15psi, then flattens out until 4000 odd rpm, where it then spikes to 21 randomly then drops back down again. Its only consistency was the 15psi early on.
It did not make a reliable 21psi on dyno and I disagree with the "calculated" crank hp numbers on that sheet.
The problem is fixed. There were a few things at play,
First, when I bought the car, the IC radiator at the front had a leak and the IAT's where through the roof, I though this was the cause so fixed that, no change.
Then I thought boost leak, engine knock, wastegate issue, bla bla bla. I could not get more than 17 psi. Car dynoed 440 WHP and 800 NM WTQ
Halfway through I involved a local tuner/racecar builder that is very good (by reputation) but he obviously could not have cared less and was just a pain in the **** the whole way through. Whilst the car was at his I got him to put a quantum ECU tune on it to see if that would change the boost levels but it did not. This was a big mistake as it added another level of complexity.
With the help of g60wall (thanks!!) and some data logging, I deduced that the torque converter slip ratio was too high, and THAT was the reason that the ECU was pulling timing and boost.
I replaced the torque converter, the TC lockup solenoid (which solved my cold harsh TC engagement) and also had the valve body rebuilt and had a sonnax kit put on the TC bore. The gearbox is now sweet and drives around much nicer than before.
I was initially disappointed as the car didn't make much more boost, 19psi compared to 17psi before. I then put it on the dyno and it did 510 WHP and 860 NM WTQ
It was then clear what the quantum tune had did, I got copies of the tables that had been changed. 6 Degress of timing advance and they had obviously neglected to increase the global torque limiter and so the car was making more power with ignition timing and less boost.
I put a eurocharged map on it and 23psi boost that holds 21psi to 5000rpm!! Only issue now is that all my plugs on one side misfire above 5000rpm so cannot dyno, but the car feels significantly faster. New packs are on there way and I hope that's the end of it now!
Thanks for the assistance everyone! Especially G60wall!!
Last edited by alexanderfoti; Jan 12, 2018 at 04:11 AM.
The problem is fixed. There were a few things at play,
First, when I bought the car, the IC radiator at the front had a leak and the IAT's where through the roof, I though this was the cause so fixed that, no change.
Then I thought boost leak, engine knock, wastegate issue, bla bla bla. I could not get more than 17 psi. Car dynoed 440 WHP and 800 NM WTQ
Halfway through I involved a local tuner/racecar builder that is very good (by reputation) but he obviously could not have cared less and was just a pain in the **** the whole way through. Whilst the car was at his I got him to put a quantum ECU tune on it to see if that would change the boost levels but it did not. This was a big mistake as it added another level of complexity.
With the help of g60wall (thanks!!) and some data logging, I deduced that the torque converter slip ratio was too high, and THAT was the reason that the ECU was pulling timing and boost.
I replaced the torque converter, the TC lockup solenoid (which solved my cold harsh TC engagement) and also had the valve body rebuilt and had a sonnax kit put on the TC bore. The gearbox is now sweet and drives around much nicer than before.
I was initially disappointed as the car didn't make much more boost, 19psi compared to 17psi before. I then put it on the dyno and it did 510 WHP and 860 NM WTQ
It was then clear what the quantum tune had did, I got copies of the tables that had been changed. 6 Degress of timing advance and they had obviously neglected to increase the global torque limiter and so the car was making more power with ignition timing and less boost.
I put a eurocharged map on it and 23psi boost that holds 21psi to 5000rpm!! Only issue now is that all my plugs on one side misfire above 5000rpm so cannot dyno, but the car feels significantly faster. New packs are on there way and I hope that's the end of it now!
Thanks for the assistance everyone! Especially G60wall!!
Hi! Sorry to revive an old thread. Are you available to speak? I am having this same issue. 😔
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