Does anyone know if there is a test procedure for the Pierburg valve.
I still only see max of 0.8-09 bar boost - perhaps it is just my gauge but I would like to rule out the valve first, does it have any moving parts inside?
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Testing Pier-Burg Valve
Does anyone know if there is a test procedure for the Pierburg valve.
I still only see max of 0.8-09 bar boost - perhaps it is just my gauge but I would like to rule out the valve first, does it have any moving parts inside?
1993 Alfa Romeo 155 Q4 , 2.0 Turbo
ive wondered about this as well as mine will boost to 15psi at times then others it will only hit 12psi in same conditions.
Same problem! When i acellerate hard from 0 km/h and trough the gears i only see about + 0,55 bar... and sometimes only 0,45 bar... but if i'm in fourth gear and about 2500rpm and floor it i can see + 0,9 bar!...
I tried to disconnetct the vacumhose from the pierburgvalve to the wastegate, and then i felt it pushed verry hard up to +0,6 or +0,7... BUT then the car shivers and shakes... like its got the hickups! I then tried to disconnect the electrical wires on the pierburgvalve, this resulted in almost no boost at all!
Will it help me if i install a manual boostcontroller?
What do i do with the wires from the ECU?
SSQ4
The Pierburg valve is activated with PWM (pulse width modulation) so youŽll need an osciloscope to watch the signal.
A quick test could be conecting the WG directly to the intake manifold. With this you should get a constant but lower boost pressure.
Also you should check where is your gauge conected to.
Connected a turbosmart boostcontroller today... didnt do something to the wires form the ECU to the Pierburgvalve, this resulted in a boost of only 0,4bar! What do i do with the ecu connection to get this working???
To start with you should disconnect the wires to the Pierburg valve. Then the engine should reach 0.6 bar and run smoothly up to the rev limit - no strange sounds or hesitation should be observed.
If this is ok. Then I should check the thin hoses to the Pierburg valve. I have switched to Silicon hoses. If the hoses are ok and the engine runs fine with the wires disconnected I should consider a new Pierburg valve. I don't know how much it costs, but probably it is woth a try instead of letting a workshop go though the electrical harness and the ECU.
Mmm, interesting thread.
I've recently got round to fitting a boost gauge to my car and I see a maximum of 0.7 bar in 1st, 2nd & 3rd gears but about 1.1 bar briefly in 4th and 5th gears at about 3000rpm which bleeds away to 0.7 bar at about 4000rpm upwards.
I'm going to fit the squadra chip I got with the car next weekend to see if there's any difference.
If you disconnect the wires from PV, boost wil be 0.45 bar constant. This is base boost of Q4. If everything is OK, then you should see 1.0-1.1 bar boost at 4000 RPM from 3rd gear up, from 4000 to 6000 boost slowly falls to 0.65-0.7 bar. Max power of 190 HP is achieved at 0.65 bar boost.
In 1st and 2nd gear there is no time for turbo to spool up and boost raises only to 0.7-0.8 bar.
If you disconnect vacuum hose which goes to wastegate actuator, boost raises to 1.5 bar where ECU stops ignition. This is the reason for strong juddering.
Wolf66: Base boost of the Q4 is 0.6 bar. Integrale Evo 2 has 0.45 bar base boost.
I have no measurements on standard configuration, but with improved inlet and exhaust system peak boost, 1.15-1.2 bar, comes at 3000 rpm. However it then falls linearly to approximately 0.8 bar halfway between 4500 and 5000. Then it holds this pressure to the rev stop.
Fiat coupe 16v turbo, New delta 16v turbo,Q4 and EVO 2 have 0.45 bar base boost (measured with standard configuration with datalogger). Integrale 16v and EVO 1 have 0.6 bar base boost.
0.8 bar at 6000 RPM means more than 190 HP on completely standard car.
are you sure that base boost is at 0.6 bar in Q4's? I believe it is as in EVO2!Originally Posted by #84
Wolf66: Base boost of the Q4 is 0.6 bar. Integrale Evo 2 has 0.45 bar base boost.
Nick
The only figure I found in the workshop manual was 1 mm actuator travel at 0.68-0.75 bar and today I don't remember where I got the figures from. However I measured my own car to have 0.58 bar base boost and it shouln't be affected by modifications in inlet and exhaust systems. The pressure was measured by the MAP-sensor.
Since the wate gate pulse width modulation maps are essentially the same in 101.03-05 softwares I can't see how the base boost could differ.
I do not know exactly the base boost level and never measured it in my car. Up today I believed it was 0.45 but probably you are right.
cheers
Nick
Interestingly there was a terrific postig on the Evoforum by "Sendo" a few days ago treating the entire boosting issue. And he confirms Evo 2 base boost of 0.45 bar while the earlier models have 0.6 bar.
I've seen this post and how to gain more power. In an older post, in this forum, "gibbonQ4" also confirmed that Q4's base boost is at 0.45 bar. I believe that FIAT Coupe 16V Turbo has also a 0.45 base boost.
Anyway, as soon as I have our Q4 back on the road I'll check the base boost level.
Cheers
Nick
P.S.
Some time ago I had send you an e-mail and I received just an automaticaly generated response. Did you receive it?
Nick, Yes you should get an automatic reply from my mail but it should have come through unless the mailbox was really full at that moment. I thought that all mails have gone through, but I haven't seen yours. Please resend it.
/A
you have a pm
cheers
Nick
hi everybody!
i'm looking if my pierburg valve is connected properly.
does the green wire is on the side of the radiator?
thanck you.
bye!
Raph
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