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View Full Version : Boost, but no acceleration


Jwurm12
06-11-2007, 03:46 PM
In second gear and higher, haven't tested 1st I tend not to rev too high in first, when the boost comes on at 3k, it feels like my car is towing something very heavy. It accelerates fine up till 3k, then it boosts up to 7 pounds quick.

Anybody know what may cause this, kinda feels like when you try to accelerate in 5th with the AC on.
DiscreetSpeed
06-11-2007, 05:17 PM
Sounds like a normal MSP with stock tune.
Any mods?
DiscreetSpeed
06-11-2007, 05:17 PM
Sounds like a normal MSP with stock tune.
Any mods?
vangj01
06-11-2007, 05:38 PM
Sounds like a hesitation problem. See this thread for some info on it.

http://www.mazdas247.com/forum/showthread.php?t=50549

You can also use the search option and see plenty of threads on hesitation. I'm still trying to resolve mine as well.
Jwurm12
06-11-2007, 07:59 PM
Sounds like a normal MSP with stock tune.
Any mods?

(uhm) Even though it has been running fine and pulling fine in every gear until now.....


It's not hesitation, It just hits a wall at 3k when the boost comes on. Like all the sudden somebody dumped a 2 ton trailer on the back of my car.
vangj01
06-12-2007, 12:07 AM
Does this happen if you WOT every gear, or just when you are driving normal and then try to go WOT? When I first bought my car the hesitation problem wasn't as noticeable. After driving it for a week the hesitation started to become more noticeable. One thing I did that has so far made it better for me was to disconnect and reconnect the battery.
Jwurm12
06-12-2007, 12:51 AM
No, it does it even when I'm just accelerating at half throttle normally, Everything is fine, even at WOT until the boost kicks in and then it just loses all of its power.
Speed_Racer
06-12-2007, 01:06 AM
your car could be knocking and pulling timing. what octane gas you running?
DiscreetSpeed
06-12-2007, 08:22 AM
(uhm) Even though it has been running fine and pulling fine in every gear until now.....


It's not hesitation, It just hits a wall at 3k when the boost comes on. Like all the sudden somebody dumped a 2 ton trailer on the back of my car.

it has been hot as hell here in tx....and that would be a big contributor to this.
Unless you have something wrong with your car..like a CEL that you havent checked..
vangj01
06-12-2007, 10:43 AM
No, it does it even when I'm just accelerating at half throttle normally, Everything is fine, even at WOT until the boost kicks in and then it just loses all of its power.


So are you saying the turbo seems to be lagging and not kicking in at all anymore? Does your boost gauge show boost? Maybe your turbo has gone bad? Do you have an Air/Fuel gauge? Does it show rich when you give it gas?
Jwurm12
06-13-2007, 05:20 PM
The car isn't knocking or getting out of time. It still runs smooth, just with little power. I run 93 only.

Yeah, it has been pretty hot, but this even happens at night when the temp has dropped. No CEL.

No the turbo isn't lagging, and it is kicking in, my boost gauge reads an even 7 pounds with no fluctuating at all. I don't have an Air/Fuel, so not sure.


I did get a helpful peice of info though this weekend. It could be excessive back pressure from a clogged CAT. I'm going to check that this weekend.

I run 93 Octane from Albertsons, anybody else run this in the Dallas area, your opinions.
crackerjakx
06-13-2007, 06:45 PM
No the turbo isn't lagging, and it is kicking in, my boost gauge reads an even 7 pounds with no fluctuating at all. I don't have an Air/Fuel, so not sure.

I did get a helpful peice of info though this weekend. It could be excessive back pressure from a clogged CAT. I'm going to check that this weekend.


What are the symptoms of a clogged cat? I would assume you wouldn't build boost quickly. But I guess the back pressure could cause manifold pressure to rise?
Speed_Racer
06-13-2007, 10:22 PM
a blocked cat would make the car feel like its under load all the time, the boost would rise superfast but the car wouldnt accelerate any faster. It would feel like it was dragging a weight under full throttle.

but all you have to do is put your hand by the muffler to tell if there's a blocked cat.
crackerjakx
06-13-2007, 11:14 PM
a blocked cat would make the car feel like its under load all the time, the boost would rise superfast but the car wouldnt accelerate any faster. It would feel like it was dragging a weight under full throttle.

but all you have to do is put your hand by the muffler to tell if there's a blocked cat.

Hm, I've had that problem before. How would you tell by sticking your hand over the muffler?
Speed_Racer
06-13-2007, 11:24 PM
depended on how bad the blockage is, you can feel the exhaust pulse or lack off to diagnose the problem. on some cars its bad enough you can tell at idle, others you might have to rev a little.
Shift2xlr8
06-19-2007, 12:44 AM
I say you just run a straight pipe, if your state doesnt have emissions. Tennessee doesnt, so when I get my new motor in (FS-ZE), I'll run a straight pipe from the down pipe back.

Chris
vangj01
06-19-2007, 09:48 AM
Now that I think about it, I might be running into this problem too. I have hesitation problems, but I also noticed that If I'm in second and if I floor it, the turbo spools and boosts up, but it seems to lag until like 5k rpm then it kicks in. Feels almost like VTEC. That's not normal on stock MSP's is it? My car is stock with an Injen CAI.

I'm thinking about replacing my spark plugs to see if that helps with this problem and my hesitation problems.
Jwurm12
06-21-2007, 03:04 PM
I figured it out, it was cheep gas. Do not use the gas at Albertson's, the 93 feels like you are running 87.
vangj01
06-21-2007, 03:27 PM
Hmmm... I wonder if that's what my problem is too then. I'm in MN and I normally pump 92 octane from Super America. Maybe I should try 92 from BP or 93 from Holiday to see if there are any differences.
alca0811
07-01-2007, 03:32 PM
I figured it out, it was cheep gas. Do not use the gas at Albertson's, the 93 feels like you are running 87.


Dude, are you sure that is the only thing that made your MSP run like that?? My car is doing the same, but has been moded out a little more than yours. . . I think. My car runs on 93 octane but also has a haltech in-cabin boost controller, greddy bov, and a walbro high flow fuel pump?
1moreMPH
07-03-2007, 06:00 PM
could be a leak. mine was like this when one of my IC pipes wasn't secure. No CEL for awhile, and afr's seemed normal for the most part. if your pipes arent leaking, maybe your bov is. make sure haltech is on the right map?
alca0811
07-04-2007, 05:58 PM
could be a leak. mine was like this when one of my IC pipes wasn't secure. No CEL for awhile, and afr's seemed normal for the most part. if your pipes arent leaking, maybe your bov is. make sure haltech is on the right map?

I know that I am gonna sound pretty lame, but what is CEL and AFR??
Brian MP5T
07-04-2007, 07:06 PM
I know that I am gonna sound pretty lame, but what is CEL and AFR??

Check Engine light

Air to Fuel Ratio
alca0811
07-05-2007, 12:32 PM
Check Engine light

Air to Fuel Ratio

Oh yeah, I knew it was that; really, I did.(lol2)
Anyways, my pipes got loose at one point, and my car would -- more or less -- turn off completely. Got that fixed and runs (relatively) fine now. I think that I might have a leak in my exhaust, because when I idle, my boost guage reads 21 psi. of vac. I know that's not too normal, is it??
ViDeo^_^kiD
07-05-2007, 12:50 PM
There is no possible way to see why your car is doing that....all anybody can do is guess. And it could very well be wrong. Truthfully it could be any number of things. Anything can make an engine run less efficiently than it did before.

My simple guess, considering your car is stock.

When you get above 3-4k RPM...when you switch gears, your turbo is surging. All MSP's do this stock...because the engineers went major cheapo.

That alone is not the only problem.
Could be a leaking turbo, could be bad plugs, could be bad gas.

You just have to know how an engine works and take the time to make it run better.

I would invest in a digital tuner and go from there.
alca0811
07-05-2007, 12:52 PM
There is no possible way to see why your car is doing that....all anybody can do is guess. And it could very well be wrong. Truthfully it could be any number of things. Anything can make an engine run less efficiently than it did before.

My simple guess, considering your car is stock.

When you get above 3-4k RPM...when you switch gears, your turbo is surging. All MSP's do this stock...because the engineers went major cheapo.

That alone is not the only problem.
Could be a leaking turbo, could be bad plugs, could be bad gas.

You just have to know how an engine works and take the time to make it run better.

I would invest in a digital tuner and go from there.

Sorry I am lost, are you refering to my prob?? or the other guys??