Raider's P2187 on a 2007 Mazdaspeed 3
- Thread starter Raider
- Start date
- Watchers 14
mangosmoothie
Greenie Member
Ive heard of brake boosters causing a vac leak with a normal pedal feel.
It will go up to 2 or so then drop STFT are all over, LTFT are good to go.
Now to find that part number.
Maybe it really could be this simple? Quick googling didn't turn up a specific part number that we can buy but I did find this post.
Sho
Silver Member
Gen 1 unlike the ms6 and pu has the check valve not in the line, but it's built into the piece where the brake booster line connects near the firewall. But I guess if that's gone bad, you can put one in line. Not sure how that's affect things though, without removing the original out of the equation
Oem is high cost. I wonder if there is anyone with a partout car I can score it from. Hoping to know if it's also really teh cause or I have a leak elsewhere causing it.
@SharksInSpace, not enough info on the check valve
Anyone look at the logs to see if anything stands out?
@SharksInSpace, not enough info on the check valve
Anyone look at the logs to see if anything stands out?
My money is on boost leak...
It would be the simpler fix.
They sell generic brake booster check valves at the auto part stores, but because we are boosted probably that supra PCV valve that seals up like a dolphins asshole would work.
It would be the simpler fix.
They sell generic brake booster check valves at the auto part stores, but because we are boosted probably that supra PCV valve that seals up like a dolphins asshole would work.
mituc
Greenie Member
Boost leaks are simple: when you go WOT you hear a big "SSSHHHHHH!!!" and the actual AFR goes in log 9s or even 8s. It's not the case here and never was according to what we can see in the logs posted on the 1st page as well as in the logs here.
The last logs posted (which has 0 views when I looked at them) looked like the problem was fixed, at least in closed loop (normal driving, idling, and so on). We still need to see a log in open loop (not necessarily WOT, but let's say high PT) even for 300-400RPM if not a 3000-4500-5000 pull in a low-ish gear such as 3rd or even 2nd if can be done without wheel spin these days.
P.S.: this is how a boost leak may sound (depends on where you have it). The clouds of black smoke behind the car will be there anyway, mind I have a double-catted exhaust:
mituc
Greenie Member
Remember to use a lower gear and not go until redline... 2k RPM will be plenty to figure if it's all good.
I think it depends more where you have it... I had all kinds and the ones around the boost tubes (hot, cold, doesn't matter) were pretty easy to hear even if the boost was 1-1.5PSI off the target.
The ones around the intake mani gaskets, throttle body gasket, brake booster clip, EGR pipe, and so on, are pretty darn hard to hear.
mangosmoothie
Greenie Member
datalog 3 had some wot around the 60 second mark.
the afr still creeps up. I don't see anything that screams why. fuel pressure is fine, ltft is fine, plenty of idc. have you asked Rob?
the afr still creeps up. I don't see anything that screams why. fuel pressure is fine, ltft is fine, plenty of idc. have you asked Rob?
mituc
Greenie Member
Log 2 was actually better, went up to 6.3k rpm in 4th right at the beginning and the AFRs were perfect. the vacuum the engine produces after letting off also indicates a healthy engine (at a first glance at least).
However, I noticed that in several points in all these logs, when he lets the acceleration off it takes a good amount of cells (4-5-6) for the AFRs to go full lean (29) which makes me think of what could cause any potentially slow burning OR moving fuel in the engine.
Then I checked the injector duty cycle in those situations and even with the acceleration pedal untouched (0% APP) there still was non-zero injector duty cycle. I'm not sure how these are in the Cobb AP software but in versatuner these tables are the Fuel Cut Decel tables. If the values there are set too low the ECU will cut the injection later. So it may be a tuning issue which manifests itself in some particular conditions, only with some types of gas or in some temperature conditions.
Other than that since during that 4th gear WOT everything looked absolutely fine I'd say you can go WOT whenever you want. That late injection cut however may wash the cylinder walls off of oil a bit and cause carbon deposits, so whether if it's tuning related or if your tuner can figure the mechanical problem it should be addressed as well.
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