WTF is up with my car? More boost=slower car

CustomMSP

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2010 Mazda RX8
Damn,

The more boost I set my turbo at the slow the car feels :mad: The most I ever put the boost up was ~10psi and that feels slower than my turbo set at stock boost. For some reason after 4k rpm the car feels like it hits a wall unless I adjust the throttle for something like 10% of WOT. Any ideas.

Thanks
 
hesitation man. Im guessing you dont have your car flashed? Get ti flashed it makes a world of difference.

-B
 
Sounds like fuel cut to me........ It's the ecm telling you to slow down or your gonna break it........ Or you could just buy a fcd....
 
Nah, guys it's not the fuel cut and I know about the hesitation fix and all, but it feels like just one BIG hesitation if I press the accelerator more than like 40% of WOT in all the gears but first, because that gear is very short and I just prolly don't feel the hesitation in that gear. I'm not flashed but I do have the FPR kit from joe. I also have a SRI. I mean I almost lost to a stock 325 auto in a short race. WTF is that?? :mad: The car just doesn't pull after 4k rpm at all. I have an appointment with mazda for next monday about some random s*** including rotor warpage at 5k miles.:eek: Do you think the throttle position sensor has anything to do with the power loss at certain throttle positions? I just don't want to get the flash so I can see if this will solve the above problem and then won't be able to go back if it doesn't. I might just have to brake down and get the flash.
 
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So.....let me get this straight....
-higher than stock boost,
-fpr kit,
Above 40% throttle in any gear above 1st. it hesitates.....
Your positive its not fuel cut......
Does it just lack power or does it buck......
Does it do it at all times or when its cold/hot indifferent......
When did it start doing it.....
Can you tell this is my occupation?
 
The boost is at stock level right now, so def not a fuel cut which I know how it feels because I've experienced it before. But this happens at stock and higher boost. I don't have an a/f ratio but I know the mixture is way to rich, because for one, when I removed my stock plugs at like 3k miles to put in copper plugs they were black as hell plus my exhaust tip is also black as hell like an exhaust on a vtec engine with 100k miles on it WFT is that? However, the car feel very powerful up to about 4k rpm. This happens mainly after driving on the highway for some time. Also, the hesitation at more than 40% of WOT comes and goes, so that's whats making this a little more difficult to determine. Once the car is in "hesitation" mode, the turbo really quites down and it sounds very faint and high pitched. Also sounds like the engine isn't producing enough exhaust gases to spin the turbo. Like it's running crappy. Plus I've noticed that my coolant is spitting out of the canister by the intake sometimes. I see some dried coolant around that area and on top of the canister as well.

Thanks guys.
 
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How long does the hesitation last? All the way up to redline?
 
All the way up to redline unless I regulate(start to back off to a certain sweet spot) the throttle and then it will start to pull like a bull but not really gain much speed. That's just prolly torque though because I'm usually crusing at around 3.8k-4.4k rpm where torque is the highest. Can you comment on the sound change of the turbo?

Thanks.
 
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You've pretty much described how my car runs more often than not. It's more powerful under 4k and at 2/3 throttle than it is above 4k and WOT. I don't have the "coolant volcano" like you though. I do have the flash so I think it's just the way this car runs.
 
The only thing I can tell you is I wish I could work on your car cause I love a challenge and I'm a glutton for punishment (I work on VW's and Mazdas).
 
I'll get back to you on that offer after my warranty expires bro hehe. Guess the open road mazda techs will have something to work on this monday hehe. Sometimes the rpm will climb but no pull with it and then all of the sudden at like 4.2k rpm the turbo will kick in and I'd feel a kick in the ass. But shouldn't the turbo be already spooled by like 3k rpm, especially our tiny turbo?

Damn, all the cars I've had so far had no top end to them. I though this MSP would change all that, but it looks like it's the biggest turtle out of them all. Oh well, we'll see what happends after monday next week.

If anybody else has any other suggestions/ideas/opinions please share. I hope this thread will be somewhat usefull for others.

Thanks, and keep 'em coming!

Girth,

Maybe out turbo isn't running right? My car runs worst at higher boost levels than in does at stock levels. Something is not right here. I have a DP on the way. Maybe it's just the super restrictive exhaust we have.
 
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Anybody think that the problem could come from the colder plugs I have in there right now? Maybe the gap is all ****** up? I did set them to .032" with that round gapper you can for like 5cents. The better gapper I had didn't have a .032" had a .034" though lol. Gonna throw the stockers back in and see. Will want them to be in place for warranty work anyway. Gonna take some pics of my plugs when I take them out. A picture is worth 1000 words as they say :)
 
dude....it took me a while also to get this through my thick head but your gonna have to face it.......Get FLASHED and it will go away...I had the same s*** going on...
 
Ladies and Gentlemen,

I have good news! I changed my spark plugs back to stock and ran a new vacuum line where my boost gauge was tapped from and left the gauge disconnected. First of all, I think that the vaccum line that goes to the top of the throttle body is not suppost to be tapped into. That's where I had my gauge tapped into and the niddle always bounced at light throttle. So the car is running much better so far and I'm not imagining this s***. No more does the car feel like it hits a wall when at WOT. It actually feels fast now at around 8.5psi I have some pics of stock and copper plugs at about 3k miles each if anybody wants to see. Pretty much they're black as heel for the length of about 3-4 threads starting from the top. I let the car idle for about 10 mins just to get it soaked with heat, and it performed much better than it used to. For some reason it feels like I lost a little bit of low end. But the new found highend makes up for all that! :D
 
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I have ZERO mods right now, mainly because I don't want to mod if it doesn't seem to be running right in stock form. And I have the flash. Looks like my MSP is simply F-ed up beyond repair.:(

There's no way I'm taking it to the dealer because I'm not driving 100 miles just to be told everything is ship shape. And if this is "ship shape" then it is the titanic. The only way my car will ever be straightened out is if I get the chance to drive a stock MSP owned by somebody that claims the flash is a "night and day" difference. Then I could take his car and my car to the dealer and ask him why mine doesn't run like his.

Thanks for showing concern though custom -- I wish it was just as simple as a boost gauge not being installed quite right.:(
 
Well, maybe tomorrow my car will be back to "normal"...I hope not though. I'll def let you know. Why don't you call them with some of the description I've wrote in this thread that you're having as well. It can't hurt to see what they say. If they tell you we'll have to take a look at it, ask them this...ok you do take a look at it and this is what you discover, how would you go about fixing this problem? You'll prolly won't get a satisfactory answer from them but its worth a try. Also, check all your vacuum hoses for a good seal. They might have some MSPs on the lot that you can test drive.
 
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