took my car down to rx7store for power FC install and tune...they got my car running right and i only have 8 psi...thats all ive had since i put this new streetport in...ive got pettit twins and lots of mods...jason tried turning up the boost and it wont go past 8-9 psi...he said to bring it back when i get full boost for the tune up...what could be my problem... both primary and secondary work perfect...there are no visible probs...zavier and jason both drove it and said its probably a vac line under the UIM seeing as i left the mazda lines that pettit put on the engine...should i replace with the silicone hoses from my old motor...have any ideas??

thanks,
randy

 

Make sure the wastegate is physically connected to the actuator.

Make sure the electrical connections to the wastegate and pre-control solenoids haven't been swapped.

Make sure the wastegate line still has the pill in it.

 

check your check valves

 

Also check for boost leaks. That's a VERY common culprit, as are bad check valves.

If you want to get new check valves, check the link out in my sig below.

Dale

 

both zavier and jason both said that the leake is probably somewhere un the UIM in the rats nest...im goin to swap over all my check valves from my other engine which i know are good...could this just be a cracked plastic hose under the UIM??...thats what they seem to think...im gonna try to fix this over a period of a couple days...if i have the UIM off im gonna change evrything over...but is there even a vac line that could be cracked causing only 8 psi...if one was cracked i would think i would have 0-1psi...i have 8-7-8 all the way to redline and both turbos are working...thanks for all the advice guys...

randy

 

dumb question: how do i go about checking for boost leaks??

 

Take off each of the rubber couplers, turn them inside out, stretch them, look for tiny cracks or cuts.

Dave

 

i have all greddy couplers...with the FMIC kit...

 

say im going to try to fix this easy boost problem in one day...what exactly should i do??replace with all silicone hose...replace with check valves that i know are good and what else??...

randy

 

Have you followed up on any of my suggestions or a few others? Many of these things are relatively easy to check and don't involve much time or effort. You might as well rule out the more easily accessible problems first.

If you think you are going to complete a full hose-job in one day....I think you are going to be disappointed....

 

do you still have the stock exhaust? If so, check the precat for restriction. Thats what happened to me, I chased the problem for a month to finally find that the precat was beginning to clog!

 

list your mods and your boost pattern.

 

pettit streetport 3mm seals
pettit ported polished twins
power fc
rx7store midpipe
greddy sp exhaust
hks downpipe
greddy fmic
greddy intake

boost is 9-8-9 but both turbos are working properly...secondary comes in at right RPM...jason said it was prolly just a cracked hose somewhere...still running the airpump but they have it unhooked...( ill plug it in and put the cat on for e-check )...there is one other weird thing though...idle...it idles pretty rough not from the airpump unhooked though...and sometimes...when its hot theres a 1000-2000 rpm surge...and there is this hose on the back of the engine...right in the middle that comes out right behind the UIM that isnt hooked to anything and has a filter on it ( i think pettit put it on ) and when it surges really bad there is a high pitched squeaking from this hose???...have no idea...

 

...

 

How long have you had the car? Was it modded at all when you bought it?

(I'm wondering if you have a stock size wastegate pill)

Dave

 

ive had the car two years...it was an auto w/ 120k...that engine blew and i put in a reman and ran that for a year...i also had it converted to 5 speed by rx7store...this winter i pick up a pettit streetport...i put that in and it only ran 8 psi with the pettit ecu...i swapped the ecu with the stock and it ran 14 psi...then all of a sudden it started running 9-8-9 again... and now i have a power fc soo i know its not the ecu or wiring...

 

Yeah, maybe it's time for an MBC on the wastegate line or a pill change. That way whenever you make a setup change you can dial it down at first and slowly tweak it up to working max.

Dave