My M5 is stalling!! pcv valve?

[M5Gonz]

I noticed that my M5 is start to stalling more often, specially when taking off in 1st gear. I heard many stories that this is common with M3's and the M5's. the pcv valve is unexpensive maintenance item, but how I change it? Any idea? do I have to remove the intake manifold? Can you guys help me out. Any pictures or instructions. thanks (boom06)

 

[Silentnoise713]

Search how to change PCV valve for a Mazda3. It should be an easy DIY item but before you take the jump, you should describe what happens before, during, and how it stalls with as much detail as you can provide in case others may have experienced the same. I haven't seen anything about this being an early faulty item. Do you have a reference?

 

[flcruising]

...my M5 is start to stalling more often...

??? Unless this is a manual, the car should never stall.

Do you have a CEL? PCV would not cause a stall or stumble, but EGR, purge solenoid valve, throttle body, mass air flow sensor, etc., etc. would. If you don't have a trouble code or CEL, then proper diagnostic equipment would be required.

 

[jimp]

If I remember correctly, changing the pcv is not all that easy on the 5, as you have to remove the exhaust header to gain access. Think there is a how to on the Mz3 board and it would apply on the 5 engine.

 

[M5Gonz]

I will

 

[M5Gonz]

I read that you you have to remove the intake manifold. so the question is, why Mazda made it so dificult to remove a maintenance item? ahhh!

 

[M5Gonz]

I will post with more details, what is going with the car.

 

[Davicho]

Is it turning off or just hesitating? Does it do it all the time or just when the engine hasn't warmed up to normal levels? Mine hesitates whenever the engine is cold and has not warmed up to the normal operating level. There is a TSB for this where they reflash the ECM but I haven't gotten around to get it done. Once it warms up though it stops doing it. Also, did you by any chance disconnect the battery or did you replace the battery or did it go dead on you? If so, every time you disconnect the battery or the battery goes dead. You must do an idle learn procedure otherwise it will idle very low and fluctuate and even could stall.

 

[flcruising]

We still need further symptom information...

Here's the procedure as spelled out in the workshop manual (verbatim) concerning the PCV. Doesn't seem too difficult to me. Of course you will have the full diagrams, etc. if you download the service manuals for yourself.

PURGE SOLENOID VALVE REMOVAL/INSTALLATION [L8, LF]
1. Remove the plug hole plate.
2. Remove the battery cover. (See 01171 BATTERY REMOVAL/INSTALLATION [L8, LF].)
3. Disconnect the negative battery cable.
4. Remove using the following procedure:

(1) Pull the vacuum tube from the intake
manifold.​

5. Install in the reverse order of removal.

PURGE SOLENOID VALVE INSPECTION [L8, LF]
Evaporative Purge Control Inspection
Without using WDS or equivalent
1. Warm up the engine and idle it.
2. Disconnect the vacuum hose which is connected to the charcoal canister from purge solenoid valve.
3. Place your finger onto the purge solenoid valve
as shown in the figure and verify that vacuum is
applied.

If vacuum is not applied, inspect the following:​

PCM output signal circuit (wiring harness,
connector)

Evaporative purge control signal​

Purge solenoid valve​

4. Run the vehicle on the chassis dynamometer and
maintain the engine speed at approx. 2,000 rpm.
5. Verify that vacuum is applied after approx. 30 s.

If the vacuum is not verified, inspect the
following:

PCM input signal circuit (sensor, switch, wiring harness)​

Intake air temperature signal (intake air temperature sensor)
Evaporative purge control signal (purge solenoid valve)
Throttle opening signal (throttle position sensor)
Load/no load identification signal
/Transaxle range switch (ATX)​

Purge solenoid valve​

I've only ever cleaned PCV's by simply removing them and spraying the insides with brake parts cleaner. They are very simple devices and you just need to make sure they don't leak vacuum and the valve inside moves freely which you can usually tell by shaking it and listening for the rattle.

 

[was98strat]

Could also be the purge valve. When mine went, I had the same symptoms. Lots of hesitation when idling. $300 repair if you dont do it yourself ( the part is $120 ) at Canadian rip-off pricing!

 

[thaxman]

I read that you you have to remove the intake manifold. so the question is, why Mazda made it so dificult to remove a maintenance item? ahhh!

Modern PVCs are supposed to exceed 100K, that's why.

 

[M5Gonz]

Ok, this is what I noticed today; it happen more often when is cold, when I put the car in first gear and if I don't apply enough gas the car goes like is dead for couple seconds. For that not to happen, I have to to depress the clutch very slow. now, the car still under warranty so I will take to the dealership and I will let you know what they say.

 

[M5Gonz]

and the car does not hesitate, it just goes dead

 

[flcruising]

Goes dead, but you said for a couple seconds??? If it's stalling (going dead), then you would have to restart it again which you didn't mention and what couple seconds doesn't imply. I definitely think you need to take it take it to the dealer.

 

[Silentnoise713]

Ok, this is what I noticed today; it happen more often when is cold, when I put the car in first gear and if I don't apply enough gas the car goes like is dead for couple seconds. For that not to happen, I have to to depress the clutch very slow. now, the car still under warranty so I will take to the dealership and I will let you know what they say.

+1 to flcruising

That description is not very thorough and rather more confusing. How does it go at all if it is dead and what does 'dead for couple seconds' mean? Sounds like you are getting it checked under warranty which is the right move at this point. If the dealer gives you the “that’s how it is” or “we can’t find any faults”, make a video (make sure audio is good) before you post back.

A few questions for you:
-Did you buy the car new or used, how long have you had it, and do you know its history?
-When did you start to experience this? Have you gotten acclimated with the car but started experiencing something new? If so, anything changed that you are aware of?
-Are you familiar with cable vs. DBW throttles (Mz5 has DBW system which tend to have some lag, unlike old school cable systems)?
-Does the car idle normally? In neutral and blipping the throttle slightly (not pedal to the metal), does the throttle respond as fast as you expect or slower than you expect?
-Check to ensure the clutch fluid is at the proper level (shared with the brake reservoir) and if you know how, bleed the whole system. Bleed farthest from the reservoir and work your way closer, the clutch should be last. I have come across some posters and truly believe the clutch/brake fluid in this car needs more frequent servicing/attention as it is a shared system and the fluids will break down faster (all that stop and go braking affects your clutch) than in a good old independent system.

 

[M5Gonz]

-I bought brand new - right has aroud 50K miles
= not really sure, if I remember correctly around 4 months ago
= maybe you are right on the DBW
- yes the car idle normally. the throttle response normally. But for some reason, when is cold (most of the time) when i take off in 1st gear sometimes goes dead for couple seconds or less (not sure how many because it happens very fast).
~ I will check on that one. Thanks

 

[M5Gonz]

-i bought the car new. Right now it has around 50K miles
-I am not really sure, I believe it started several months ago
- thank you for the DBW info. didn't know about the lag
-yes car idle normally. yes the majority of the times the throttle respond normally. But again, the lag happens most of the time when is cold and in 1st gear. and when it happens the car goes dead for 1 or 2 seconds (I havent take the time because it happens very fast)
-thank you for the info

 

[M5Gonz]

I just want to thanks everybody for all your inputs. Some of the responses are to complicated for me (stash), but they are all good. Now I can go to the dealership better prepared and able to explain them what is happening with my car. (drinks)