Help me with Mazda 6 surging please

Temperature sensors can be tested with an ohm meter. Ambient temperaure of 68 degrees F should read 37,000 ohms. If it reads lower is is defective.

In reply to wvumtnbkr: Hi found your Jan. 31 2013 mazda 6 post about surging at all speeds while Google searching the same problem with my wife's 2007 M6 2.3. It was fine one day but started the next day as she left for work. Your description of symptoms is the only one that I've seen that matches mine. It starts and idles fine (-21 deg. F here)runs great except for surging/pulsing. No CEL, 11-28-13 dealer test ride (with me)then diagnostic amounted to variable valve timing fail "P0011" and a repair quote of $2200.00 + tx + small parts & fluids = $2700.00 approx. 212K on car still driving no better or worse since prob. started. Would you tell me what your "FIX" ended up being. Plugs, oil & trans fluid all chg'd. I can replace eng. for less $. Mazda tech an Hr.+ code hunting. THANKS for any input. Al Wice

For me, it was the o2 sensor. Unplug the sensor on the engine side of the cat and see if it goes away. It did for me. I got a new sensor for 140$.

Hope this helps!

In reply to wvumtnbkr: Thanks for the fast response I wasn't sure how it would go on an post almost a year old. From what I saw (new to this) you didn't get a lot of response/help to your query. I'm going to try this as soon as I can get her inside out of the snow and @#%* cold. Thanks again, Al Wice, Stoney Creek On. Can.

In reply to wvumtnbkr: Rob thanks for the O2 sensor tip Jan.8 14. Took car to an out of town Mazda dlr. near my work and had them diagnose on Jan.22 14. Guess what? O2 sensor at manifold. Satisfied with that because of your response I gave the go ahead for the next day when the part came in. Runs great! $378 repair + $112 + $184(2 diagnostics)= $683. Pricey but better than $2700 at the local dlr. for the wrong repair which I'm sure they would have informed me that more repair was required after they discovered their mistake, or it was BS and I would have got the sensor and charged for VVT. I will be confronting them as this my second integrity issue with them. I pity the nontech, women and elderly that get hosed for auto repairs. Thanks again aldow

Wow, that's alot! Glad you got it fixed!

wvumtnbkr, Did you replace your upstream 02 sensor? just want to be sure before i go ahead and replace mine, because it is doing the same things you explained that your wife's car was doing.

Unplug it first. If it goes away, that is the issue.

thank you very much for your help.I already replaced the 02 sensor and my car is running like new again. If it was not for this website and you i would have spent a lot more money throwing parts at it trying to fix it. hope you have a great day and god bless you and your family.

I am pleased as punch that this forum is helping new people out. I'm hoping the ad revenue on the forums is helping the Suddards out, too.

Hi I just created an account to thank you wvumtnbkr half dork.lol. My 2006 Mazda 6 was running the same as yours. My husband who restores cars for a living checked it all out, hooked it to a code reader and it came up the MAF we replaced that the car ran worse, 3 of his friends looked at it couldn't come up with anything after that I ended up taking it to the dealership for a diagnostic check ($65 would of been $99 but I had coupon) they said change spark plugs and the PCV hose and 'wanted $675 (witch later found out would of probably been more$) so after replacing the PCV valve and hose (which required taking the whole intake off 8hrs later) and all of the gaskets since he had the intake off the car didn't run any better so he was not very happy and said I don't know I just don't know we are going to have to take it somewhere I just don't know what to do ahhhhhh! My last ditch attempt was to just google the symptoms before I had to go pay the big bucks and hope they found something, and this page came up and I read all of the comments and seen that you replaced all the same parts, I went out to the garage and said please just check one more thing for me and told him about the post you had about the O2'sensor he said ok but was obviously annoyed he unhooked it and the problem went away I ordered the part yesterday and we replaced it this afternoon car runs great! I have put about 30 miles on it today and no problems. Thank you so much for your posts I'm sure you saved me a ton of $$$ good karma coming your way buddy!!

Thank you so much I created an account just to post and thank you!!! In reply to wvumtnbkr:

Wow, thanks! Glad that I could help!

Just one more reason why I love this forum! Rob R.

Wow, this thread was resurrected for awesome. Hi all new peeps!

Found this forum from google trying to figure out what is going on with my wife's 2005 mazda 6 (4 banger). Main symptoms seems to line up with those in this forum. Hard shifts, even in 4th gear. Harder to brake because it seems like the engine is not letting off completely. When I put it in neutral, it revs up and down between 2k and 3.5k rpm like there is a ghost foot on the gas. Not sure if these are the same symptoms, but I am going to take it in tomorrow and I will update with what result I get (another forum discussed a throttle position sensor). I am 0% handy, so make sure any questions to me are dumbed down to my level.

Ryeguy52 wrote: ... I am 0% handy ...

Welcome to the club.. I guarantee that if you hang out here, you'll get up to at least 1 or 2% in no time :)

Update: Tried to take my car in today. Amazingly (and unfortunately) all symptoms are gone and car is driving normally. They tried to do a diagnostic, but it had thrown no codes while having problems and is functioning fine now. I have traded cars with the wife and I guess I will just wait until it happens again. Mechanic pointed me towards a service bulletin (ENGINE SURGING AT 40-50 MPH WITH LIGHT THROTTLE), but I don't think that is it at all. I mean yesterday I had a hard time braking because the engine was working against me and I almost rear-ended someone. Will update when I have something helpful.

If the issue is internal wiring in the o2 sensor (i don't know how, exactly, the sensors are failing and I don't have the issue, I just happened to be walking by), then it could totally be an intermediate thing until the sensor "fails more"..

The revving by itself is concerning. I wouldn't think an o2 sensor could do that.

I am thinking bad engine mounts or a vacuum leak.

Oh oh, what about a sticky/dirty throttle body?

You can take your car to advance auto or AutoZone and check for codes. You can also look at each sensor in real time with the scanner. If you push on the throttle pedal (engine not running). It should read smoothly from 0 to 100%. If it doesn't, I would guess GPS.

Tps, not GPS.

Been a while I know. I just wanted to update now that I have some good information. First, this problem only ever caused the check engine light to turn on once and then very, very briefly. The code was not stored (checked by autozone and at dealer). I tried a really cheap fix first, and honestly it worked for over a month before the problem returned. The cheap fix was to simply disconnect the battery overnight once. When it came back five or six weeks later, I took it into the dealer. From my earlier research I knew that Mazda put out a technical service bulletin on surging at 40 to 50 mphs in Mazda 6. The fix suggested there, and the one that worked for me, was just to have the dealer update the firmware. I think the tech said that there were about 15 updates in all. Cost came in under $100 and the problem has not reoccurred. In case anyone cares, I also have more specific symptoms. Problems generally occurred in the afternoon when the car had been in the sun all day during work and I was running the AC on the way home. Surging typically started about 10 minutes into my drive and usually coincided with speed changes in traffic on a highway (changing speeds from 40 to 70 according to traffic). When it did occur, the best description of the problem is that it felt like the pedal would jerk to respond to acceleration (jerk after slight delay kind of like it can when using cruise control) and then engine rpms would stay higher than they should after letting off the accelerator. The rpms would eventually go back down to where they ought to be if I kept coasting for 20 seconds or more. Sometimes the engine would really want to keep the rpms up and would actually fight you to brake (the brake becomes as hard to depress as it is when the car is turned off). The problems were never consistent and would usually resolve themselves once the car was in park and idling for more than 5 minutes. No doubt that very little of that will help. If you are having something similar, go to the Mazda dealer. $100 bucks for the firmware updates is well worth it.

In reply to wvumtnbkr:

If the problem ever comes back after the firmware updates I have tried, I will check the sensors with the scanner as you have suggested. Will a dirty/sticky throttle body show up in this test?

2006 Mazda 6 w/5-speed. 110K miles

Surging idle and hesitation on acceleration. No check engine light and all diagnostic data seemed normal.

Unplugged the upstream O2 sensor and this issue went right away. I’ll update again after the O2 swap, but things are looking good so far.

Interestingly though, there is no CEL or trouble code with the upstream sensor unplugged.  Whatever....

Thanks so much!!

In reply to pdx :

Same issue with pdx...

Same solution too...

Thanks to the author of this thread...

2007 Mazda 6i 5speed AT

In reply to pdx :

I've put a couple hundred miles on the car and everything is working properly after the O2 sensor install.  I went with Bosch 15374 Oxygen Sensor from Amazon and it was an exact fit.  Cheers!