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

 

it sounds like you didn't put a vacuum hose correct or you have a bad solenoid or check valve....

 

It is hard to say, yiou should go thru all the lines again and check all the solinoids.

 

did you mess with the pills in the pre control? how about having the solenoid on the front of the intakes connectors swapped?



mike

 

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

 

Just to clarify, when you replaced the hoses with silicone, did you replace the ones that have the pills in? If so, did you transfer the pills to the new hose. If that's not the problem, a good resource for help is here...



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.

 

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

 

you might, the "new" turbos were starting to filter in. if your wategate actuators are gold, then you prolly dont have pills



mike

 

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.. ?

 

If the dealer replaced the turbos then there's a good chance they screwed something up. Maybe the turbos have the pills built-in since they are newer ones, but maybe the dealer used your old hoses with the pills as well, i.e., there may be two sets of pills. That would definitely f* things up. If this is not the problem, then the only thing I know to tell you is to check every hose, solenoid, and actuator until you find a problem. The shop manual and the link I posted before has all the info you need. Boost problems suck.