Boost Gauge Oddities
#1
Instructor
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My first post woo hoo.
I just brought home my new (to me) 951. I come from the 914 world so these newfangled water cooled cars confuse and frighten me. No, not really.
I have read many of the postings having to do with the stock boost gauge but have not seen this problem yet. At start up my boost stock boost gauge reads .4 bar. When I really get into the throttle the needle just hits 1.2 bar. I can hear and feel the turbo at about .8 but it still doesn't feel like a real kick in the pants like I thought it would.
The other problem I am having is the oil pressure needle dances quickly at 5 but never really comes down.
I have not had a great deal of time with her to troubleshoot yet but any help would be appreciated.
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I just brought home my new (to me) 951. I come from the 914 world so these newfangled water cooled cars confuse and frighten me. No, not really.
I have read many of the postings having to do with the stock boost gauge but have not seen this problem yet. At start up my boost stock boost gauge reads .4 bar. When I really get into the throttle the needle just hits 1.2 bar. I can hear and feel the turbo at about .8 but it still doesn't feel like a real kick in the pants like I thought it would.
The other problem I am having is the oil pressure needle dances quickly at 5 but never really comes down.
I have not had a great deal of time with her to troubleshoot yet but any help would be appreciated.
#2
Burning Brakes
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The gauge reads on an absolute scale so 1 bar=1atm(approxamately) so when you turn the car on before cranking it the gauge should read 1 bar. The .4 bar at idle is good because you car should be pulling about .6 bar of vacuum. The 1.2 bar of boost is your problem though. You should get 1.6-1.8 bar of boost on a stock car, which translates to .6-.8 bar above atmospheric pressure. Also as a side note the stock gauge is notoriously inaccurate at the extremes, so don't trust it to be accurate at reading any pressure above 1.7-1.8 bar.
regards,
John
regards,
John
#5
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As hosram_951 says, boosting to 1.2 bar is your car's safety mode. Do a search for "1.2 bar" and you'll learn a fair bit about this. Basically, if the car detects an issue (like overboosting), the computer that controls the boost (called the KLR) will automatically limit boost via its control mechanism, which is the cycling valve. There are a variety of issues that could cause the car to default to this mode, most of which are not too tough to sort out.