Please Help Me Analyze My Boost Pattern
#1
Hey guys. My '93 is stock except for a downpipe which I just put on. At the same time I replaced all the vaccuum line with silicon lines (what a fun job!). I was very careful and I'm 95% sure not lines are kinked or pinched.
I also installed a boost gauge so I don't know if these problems existed before I put on the gauge or not.
Here is my boost pattern is erratic:
If I slam on the car in 2nd starting from around 2500rpms the boost will jump to almost 15psi (too high right?) and then settle back down to around 11psi very quickly and stay about there.
If I slowly depress the accelerator to the floor from a dead stop the boost will initially go to about 10psi and then drop to 7psi for the rest of the rpm range.
Once in a while I get was appear to be a somewhat normal 13-11-13 boost pattern. But it's not predictable.
If I give the car 1/4 gas from a stop the turbo spool up almost instantly to about 5psi and then drops suddenly to zero psi.
What worries me most are the momentary ~15psi boost spikes that occure when I slam the car in the mid rpm range. I'm never really supposed to run over 12psi right?
What pattern should be normal? If mine is screwed up what do you think might be causing it? Bad Solenoids? Bad vaccuum line? Downpipe?
Any help is VERY MUCH appreciated.
I just want to not have to worry about blowing up my car... is that too much to ask? Maybe I should stick to my Miata's...
Thanks guys!
-John Magnuson
I also installed a boost gauge so I don't know if these problems existed before I put on the gauge or not.
Here is my boost pattern is erratic:
If I slam on the car in 2nd starting from around 2500rpms the boost will jump to almost 15psi (too high right?) and then settle back down to around 11psi very quickly and stay about there.
If I slowly depress the accelerator to the floor from a dead stop the boost will initially go to about 10psi and then drop to 7psi for the rest of the rpm range.
Once in a while I get was appear to be a somewhat normal 13-11-13 boost pattern. But it's not predictable.
If I give the car 1/4 gas from a stop the turbo spool up almost instantly to about 5psi and then drops suddenly to zero psi.
What worries me most are the momentary ~15psi boost spikes that occure when I slam the car in the mid rpm range. I'm never really supposed to run over 12psi right?
What pattern should be normal? If mine is screwed up what do you think might be causing it? Bad Solenoids? Bad vaccuum line? Downpipe?
Any help is VERY MUCH appreciated.
I just want to not have to worry about blowing up my car... is that too much to ask? Maybe I should stick to my Miata's...
Thanks guys!
-John Magnuson
#6
Originally Posted by RX73rdgen' date='Jan 17 2003, 09:58 PM
Nope, didn't mess with the pills in the pre control. I don't think I swaped the solenoid connectors... I'll double check. Thanks guys
http://www.scuderiaciriani.com/rx7/boost_problems.html
It might not solve the problem, but it'll help you figure out what all those hoses and solenoids do.
#7
No. I just replaced all the hoses with silicon that are on the top and side of the engne. I was replacing my fuel injector o-rings so I was in there anyway. I haven't touched the hoses with the pills.
The turbo was replaced in '99 with a new factory turbo by the dealer. Does that mean it probably has the restrictors in the nipples now anyway?
Thanks for your help guys.
-John
The turbo was replaced in '99 with a new factory turbo by the dealer. Does that mean it probably has the restrictors in the nipples now anyway?
Thanks for your help guys.
-John
#8
Originally Posted by RX73rdgen' date='Jan 18 2003, 11:49 AM
No. I just replaced all the hoses with silicon that are on the top and side of the engne. I was replacing my fuel injector o-rings so I was in there anyway. I haven't touched the hoses with the pills.
The turbo was replaced in '99 with a new factory turbo by the dealer. Does that mean it probably has the restrictors in the nipples now anyway?
Thanks for your help guys.
-John
The turbo was replaced in '99 with a new factory turbo by the dealer. Does that mean it probably has the restrictors in the nipples now anyway?
Thanks for your help guys.
-John
mike
#9
15psi...
hhmmnnn...
if i recall correctly...factory ecu will not allow you to exceed a certain level...
the result would be like hittin a brick wall....fuel or ignition cut as a preventative measure...
on second thought....this could have been my untuned pfc at the time...
any chance on a faulty gauge.. ?
hhmmnnn...
if i recall correctly...factory ecu will not allow you to exceed a certain level...
the result would be like hittin a brick wall....fuel or ignition cut as a preventative measure...
on second thought....this could have been my untuned pfc at the time...
any chance on a faulty gauge.. ?
#10
Originally Posted by RX73rdgen' date='Jan 18 2003, 11:49 AM
No. I just replaced all the hoses with silicon that are on the top and side of the engne. I was replacing my fuel injector o-rings so I was in there anyway. I haven't touched the hoses with the pills.
The turbo was replaced in '99 with a new factory turbo by the dealer. Does that mean it probably has the restrictors in the nipples now anyway?
Thanks for your help guys.
-John
The turbo was replaced in '99 with a new factory turbo by the dealer. Does that mean it probably has the restrictors in the nipples now anyway?
Thanks for your help guys.
-John