loss of power when hot/higher gears rpms

hey guys,
first of all thank you for all of you input on the other threads similar to this one, they gave me a place to start and a lot of ideas as to what it could be... but after all i am very lost

So i just bought Sunlight Silver #1986, it was the last one sold in colorado, and shes been pretty good to me except for this...

It seems like when the car is good and hot after driving around in normal conditions and boosting a fair amount under full acceleration it hits a wall, it reaches full boost seemingly ok but the motor seems not to react to it at all like its accelerating as if the turbo is not even there and sometimes at about 5500 it seems to be released from whatever this is and accelerate normally until shift or redline. Mods are: Injen CAI, Custom upper IC hard Pipe, Blitz DD BOV, Apex'i Cat back, and boost/ oil pressure guages.

-Boost reading between 5.5 and 7 at full
-Vac reading between 15 and 20 at idle
-Vac line for boost guage tapped at the U on the right side of the intake mani as per the "how to" on this forum
-No CEL

Things ive tried in order (thanks to other posts):
-Hesitation ECU reflash from Mazda performed 2004
-Thought it was fuel related, seafoamed the s*** out of the car via the brake booster plus lucas fuel additive to clean the injectors
-Checked all IC and turbo connections for leaks (none) and cranked everything tighter
-replaced almost all vacuum lines including original boostguage tap which was in the middle of a line between a sensor to what looked like the FPR.. improve BOV performance but otherwise no dice.
-Cleaned air filter really well
-replaced plugs with double platinums (old plugs didnt appeared to be fouled) HELPED A LITTLE

Please help i am so lost and i dont want to keep throwing parts at it or take it in to the stealership. My next attempt was going to be the WGA, but i am unconvinced that this is what it is, doesnt seem to be boosting slower or taking time to build.. but i dont know much about the symptoms... any suggestions or ideas as to what this could be would be greatly appreciated.. i hope i was thorough enough with my description

msp1986 said:

It seems like when the car is good and hot after driving around in normal conditions and boosting a fair amount under full acceleration it hits a wall, it reaches full boost seemingly ok but the motor seems not to react to it at all like its accelerating as if the turbo is not even there and sometimes at about 5500 it seems to be released from whatever this is and accelerate normally until shift or redline. Mods are: Injen CAI, Custom upper IC hard Pipe, Blitz DD BOV, Apex'i Cat back, and boost/ oil pressure guages.

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Sounds like fuel cut or heat soak to me.

fuel cut maybe... what could be causing it tho? and would heat soak really bog it down like that? i know nothing about heatsoak anyone care to enlighten me on fuel cut and heatsoak? thanks very much for everyones support it makes owning this car a lot easier

Mine seems to be the same way! When ever its been running for awhile there just doesnt seem to be any power at all. But when its been running for a few mins and a bit cooler it runs like a champ..... Would a new intercooler and hardpiping help this you think?

it makes sense but its hard to belive that these cars had this heatsoak issue from day one.. i could be wrong but it would be good to know.. i think mine is having WGA issues but i know nothing about symptoms of that etc

Sounds like heatsoak but it could very well still be a bad tune. These cars still run uber rich even after the flash. Your best bet would be to get some sort of engine management if that turns out to still be the problem.

i think it could be your intercooler cuz my car does the same thing today after driving 160kms for a while it seemd to loosed power and not boost as well i think you need to upgrade to the bigger side mount intercooler and hardpipes im gonna upgrade my pipes asap but protege garage has been slow to ship my items

msp1986 said:

it makes sense but its hard to belive that these cars had this heatsoak issue from day one.. i could be wrong but it would be good to know.. i think mine is having WGA issues but i know nothing about symptoms of that etc

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These cars definitely have heatsoak issues. The stock intercooler (and pipes for that matter) are complete junk. To check the wga issues, blow into the vacuum hose going to the wga. If its solid, you're good; if you can blow air into it at all, its not good. If your wga is on its way out, it could lead to overboost and cause the fuel cut.

its weird because it seems only to happen after ive been driving a while and things are good and warm. i guess it could be heatsoak, but it feels like my problem goes in and out where with heatsoak i would assume it woould be constant after a certain temp is reached. it feels like the motor doesnt even react to boost, and sometimes miraculously at 5500 its released and accelerates fine. it feels calculated is my point. like something the motor or ecu is doing. if its wga boost would probably be higher than 6 to cause fuel cut? and if its a bad tune wouldnt it make it run like s*** not just when its hot? im sitting at 15 to 20 vac at idle im not sure what stock vac should read but a vaccum leak wouldnt cause issues just at temp either would it?

I'm not sure what vacuum is considered "normal" in Denver because of the elevation. Higher elevations should have lower vacuum right? I know down here in FL, 20-22 is normal. What about coils and wires? They seem to make your car run funny when they go bad. Or PCV? I changed out my PCV and it ran a little better.

I would guess its the msp super uber insanly rich tune.

im gonna try pulling my plugs down to standard or single platinum and gapping them to .030 and cleaning the MAF and see what happens. aside from that i am completely lost. could be fuel related or a vac leak i just dont know....

you should get a upgraded side mount and see if that helps let me know toocuz i might be getting one soon

That's next on the mod list for me. Hard pipes upgraded fmic or smic and NBC of some sort (suggestions on what to get for all of this?) also read my reply on the wga question about an intake Mani leak or crack.. Think this may help us all with this problem

I don't think an intercooler would do much good. I had the problem with my msp and i have upgraded the intercooler. I just put it the joe p fcd, i was skeptical but no more cut. i would recommend a a/f ratio gauge to keep an eye on it though. and a good tune.

**** mines doing the same thing...

and ive got a fmic....i mean exaclty what your describing. ive got a wideband and im running 11.5-12.0 afrs!!!!!

so you 2 are saying that putting in a new intercooler will not solve the heat soak issue?

mp3-79bronco said:

**** mines doing the same thing...

and ive got a fmic....i mean exaclty what your describing. ive got a wideband and im running 11.5-12.0 afrs!!!!!

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i go thru the same thing. it really depends tho...not on weather but on how the msp is behaving that day. if it is happy, it feels peppy and responsive, but if it sad, it feels sluggish and non-responsive.

sometimes i hit 13.5 afrs and get MILs, other times it deeps to the 10s.

this car is ******* haunted!

anyways, altho a FMIC does help with heatsoak, the issue might lay somewhere else.
a bad O2 sensor can act right sometimes and others just like s***. remember that the ECU is contantly chekcing the sensors, and it acting up like that and then being ok, the ECU might not think is a bad O2.
also, check for cracks around the exhaust manifold, check your PVC valve for leaks and check your timming.

just some ideas...not everything fuel-cut related is FUEL. it could also be dirty filters, timming belts, O2 sensonrs, MAF sensors....it could be anything!
****, i hate ODB2!

im gonna try the stage colder plugs

just an idea, but how's your by-pass valve? I just skimmed through here and didn't see anything, but they heat up and leak