Problem... ECU or Boost?

BlkZoomZoom said:
The new cold pipe is because they found the vacuum/boost leak. Probably the nipple for the bpv was loose/cracked.
Correct me if I'm wrong but the nipple for the BPV isn't on the cold-pipe. It's between the intake and the hot-pipe. So maybe the leak is at the joint just before the TB (that little plastic bracket glued in the pipe to support something...). (part #31 on the picture below)

MAZDASPEED_PARTS_CODED.jpg
 
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You are correct. Still from a leak more than likely.
 
SpeedBeaver said:
Ok I'll begin by the beginning, this morning it was quite cold outside (living in Canada so I have crappy weather right now). I noticed a low idle when I was stopping on red lights (600 rpm) but I tought that it was because of the weather and nothing more.

Then I took the highway and went back to my place. During the travel, I had to do a quick passing and I noticed that my engine bogged for a second.. I was like WTF was that? Then I went back to the right lane and tried again but I watched my cluster that time. So quick acceleration, let go of the gas pedal then pressed the clutch pedal to the floor. Then I saw it: The rpm went from over 3000 to ZERO and the engine stalled. The whole cluster lighted up like a freaking Christmas tree. Check engine, brake light, battery light, etc.. Then I had to restart the engine while still roling (cuz that time it didn't restarted by itself). So I spent the rest of the road doing heel-n-toes while braking so the damm engine won't stall.

I tried it again on an empty road to try to find more details so here it goes:
-over 3000 rpm to zero (stalls)
-under 3000 rpm to 500 (near stalling)

I'm on my winter setup now: all stock except for CustomMSP's SMIC wich was too much work to remove for winter. I was running 9psi last summer so maybe my BPV is just done for. So it looks like a BPV issue but then again, the low idle could be due to the ECU not injecting enough gas.

I'm thinking of trying to reset the ECU and go for a test run but checking the BPV and vaccum/boost lines at -15 Celcius is just not possible.

So I'm asking for your toughts about all this. Any advice?

I just got my car back from the dealer. I had pretty much the same problems that you were having. Stalling, and would not hold an idle to save it's life! On my car it was 2 issues. 1st Vaccum leak due to Faulty EGR Valve. (valve was stuck open so they replaced both the valve and gasket). 2. I had a K&N and the MAF Wire was dirty (from the oil on the filter). They cleaned the MAF with electrical cleaner. Runs like a top now!
 
SpeedBeaver said:
Correct me if I'm wrong but the nipple for the BPV isn't on the cold-pipe. It's between the intake and the hot-pipe. So maybe the leak is at the joint just before the TB (that little plastic bracket glued in the pipe to support something...). (part #31 on the picture below)

MAZDASPEED_PARTS_CODED.jpg

You really should put the author of the original drawing up there to make everyone happy.






P.S. I did that drawing with color in 2003 when the MSP was BRAND NEW.. :)
 
Brian MP5T said:
You really should put the author of the original drawing up there to make everyone happy.






P.S. I did that drawing with color in 2003 when the MSP was BRAND NEW.. :)
Lol I didn't knew who did that drawing, saw it on a thread and saved it a year ago.
 
Beaver i know mine isnt a Mazdaspeed but i had the same issue 2 years ago....

Stopping at a red light... pressing the clutch... idle fall to 0 and car stalled...
It had nothing to do with boost leak on mine for sure.... took it to a dealer

Problem: ERG valve problem... was stuck open.... was replaced NOT UNDER WARRANTY (deadhorse and car ran like new after replacing it!

I wish i could return in the past just to clean that EGR valve and fix the problem instead of paying 380$cad for a new one...

SO my question: Has EGR valve been checked?

Can't wait to see what was wrong on you msp! Best of luck!
 
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SpeedBeaver said:
They said they checked it.

I know that on mine, they tried everything else first to no avail. I had checked everything for a vaccum leak and it was all tight. No codes pointed to the EGR. Then a second Mechanic looked at it and stated that he had seen a bad EGR cause the same problem. He tore it all apart and upon removal, determined it to be bad. You might want to check with them to see if they have gone that far with it.
 
i just finished fixing a mx3 with a similar problem. It turned out the vacume solenoid that activated the EGR had a loose vac line so the solenoid was not functioning properly, i replaced the line and zip tied both ends tight and it works fine now. Owner said it didnt start happening until it got cold, we are in canada also. I would check and recheck absolutely anything vacume related to the vehicle. does your gauge have boost and vac? what vac are you reading?
 
jeffmsp said:
i just finished fixing a mx3 with a similar problem. It turned out the vacume solenoid that activated the EGR had a loose vac line so the solenoid was not functioning properly, i replaced the line and zip tied both ends tight and it works fine now. Owner said it didnt start happening until it got cold, we are in canada also. I would check and recheck absolutely anything vacume related to the vehicle. does your gauge have boost and vac? what vac are you reading?

My boost and vac were ok: 20-22 in and 7 psi.
 
weird. you try letting the dealer drive the car? they should be able to figure it out. if not head over to westowne mazda. ask for niki, tell him jeff from APA (automobile protection association) sent you and explain whats up. one of the mechanics there works on a fully built speed (has everything, i mean everything) that he claims runs 12s and faster on the street. he is named mooed i think.very intelligent mechanic. he doesnt used message boards or the net really. but ive heard alot about his speed from several guys there. one of them took a boot in my car when i was running 14psi spike down to 12ish at redline and he said that i would not have even be able to keep up with the guy, not even close and i figured she was moving pretty good so he must be really fast. built motor, custom IM, EM, T3/T4 etc.
 
jeffmsp said:
weird. you try letting the dealer drive the car? they should be able to figure it out. if not head over to westowne mazda. ask for niki, tell him jeff from APA (automobile protection association) sent you and explain whats up. one of the mechanics there works on a fully built speed (has everything, i mean everything) that he claims runs 12s and faster on the street. he is named mooed i think.very intelligent mechanic. he doesnt used message boards or the net really. but ive heard alot about his speed from several guys there. one of them took a boot in my car when i was running 14psi spike down to 12ish at redline and he said that i would not have even be able to keep up with the guy, not even close and i figured she was moving pretty good so he must be really fast. built motor, custom IM, EM, T3/T4 etc.
Thanks for the help but I will not take my car (wich is running like a bit*h right now) from Montreal to Toronto. I have to do heels-n-toe on every stop or red light so he damm thing won't stall.


Brian, you've got PM
 
haha sorry didnt realize you are in montreal. that guy with the fast MSP is in Oshawa, but works in tdot. still too far lol do you know any local msps? try switching to their BPV to see if thats the problem. Are you getting excessive turkey? Is the valve backwards? There is a arrow on it showing which way to put it.
 
jeffmsp said:
haha sorry didnt realize you are in montreal. that guy with the fast MSP is in Oshawa, but works in tdot. still too far lol do you know any local msps? try switching to their BPV to see if thats the problem. Are you getting excessive turkey? Is the valve backwards? There is a arrow on it showing which way to put it.
What I did so far:
checked every vaccum line
checked all the pipes on the turbo system for leaks
took my CustomMSP SMIC out and putted my OEM smic in.

What the dealer did so far:
changed the MAF
changed the BPV
changed the TB
changed the primary O2 sensor on the mainfold
changed the ECU
checked the cats for bottlenecks
checked the mainfold for leaks
rechecked the vaccum lines
rechecked the pipes
checked the EGR (dunno at what extent they did)


And yeah, I know lots of local msps. I'm co-admin on a french canadian forum (www.mazdatuning.com)
 
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