Big problem with my CX7. Spark plug Fouled. Help
- Thread starter CX7 Driver
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CX7 Driver
Member
Finlay Mazda got back to me, and it is the same old thing they suggested that I go to a different dealer to service my car. (cricket) That will be my next move. But now that the temperatures are getting warmer the problem is going away. I'm just worried that next winter it will be back.
I have a similar issue.....
My wife's 07 (April) CX-7 drives like a sport's car......very peppy and quick. She had a few hundred miles on the odometer when she bought it last month (probably a demo or salesman driver).
My BRAND new 08 CX-7 seems a little sluggish. I did the sparkplug cleaner procedure and we both use the same Sunoco 94 gas. I just rolled over 1k on the odometer. Her car is so much more fun to drive!
I'm wondering if the difference isn't the engine programming, but perhaps the transmission? What bothers me is you'd think the 08 would have the most current programming. The TSB's that pertain to my situation are for early build 07's.
My wife's 07 (April) CX-7 drives like a sport's car......very peppy and quick. She had a few hundred miles on the odometer when she bought it last month (probably a demo or salesman driver).
My BRAND new 08 CX-7 seems a little sluggish. I did the sparkplug cleaner procedure and we both use the same Sunoco 94 gas. I just rolled over 1k on the odometer. Her car is so much more fun to drive!
I'm wondering if the difference isn't the engine programming, but perhaps the transmission? What bothers me is you'd think the 08 would have the most current programming. The TSB's that pertain to my situation are for early build 07's.
The latest round of updates was released after 08 production started, they might still apply. Worth checking anyway.
HI, folks. I've read this thread earlier, when I was trying to figure out what was wrong with cold weather driving on my car, but could not get the dealer to do anything until recently.
Mazda has finally issued the TSB for the O2 sensor. I went to my dealer and based on my history of complaints and their tests they have replaced the sensor in my car. Results - well, drives much better, but what is more interesting, the MPG went up from approximately 17-18 (70% hwy 30% city mix) to about 20 (still testing, only used 1 tank so far).
Mazda has finally issued the TSB for the O2 sensor. I went to my dealer and based on my history of complaints and their tests they have replaced the sensor in my car. Results - well, drives much better, but what is more interesting, the MPG went up from approximately 17-18 (70% hwy 30% city mix) to about 20 (still testing, only used 1 tank so far).
i find the ECU doesnt make use of higher than 91 octane fuel, as well high octane and cold weather seem a problematic combo in stock. The combination of the ECU overcompenation, cold weather, high octane and direct injection = one 'chilly' combustion chamber and poor fuel burn
Rick's CX-7
Member
- :
- 2014 Mazda6
I saw better mileage on 87-89 in the winter than with 93. I saw better performance with 93 during the hotter months. I agree with your statements.
Rick
The ecu will only advance timing to a certain point. Higher octane won't change the advancement or temperature of combustion. Infact, atleast where I am, the highest octane available is brewed with methonal and burns hotter because it burns leaner.
Since I have just rolled over the 1000kms range on the cx, I haven't really learned much about it but most turbo engines have a knock sensor that will pull timing out of an engine as a safety measure when pinging or detonating (engine knock) is detected. That could explain the problem. If you do have dirty plugs and you are not getting a hot enough spark to ignite your combustion chamber every rotation then your timing and power are being held back. Just a thought, not that it helps.
I would also say that if it was heat that disolved the carbon, running the car under load with boost is going to significantly increase exhaust gas temperatures (by probably 400 degrees)and burn your carbon more effectively. So I don't see how running your car at 4000 rpm for a minute or so in park does anything other than waste gas. Do these cars use an iridium plug or what?
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TRXSandRacer02
Member
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- 2000 Mazda 626 LX
these are direct injected engines, never mind all that. You need to turn key to on, put pedal to floor to put the pcm to clear flood mode, crank it for 15 seconds, 2 times in a row, turn key off, turn key on and crank normal and when it hits hold the rpms at about 2000 to 2500 rpms to clean the plugs. If your o2 sensors read fine there is no need to replace them. The tech who recomended an o2 sensor shoudl abviously know that when cold, they dont even read because it is in open loop which means pre calibrated pcm tables. The plugs are iridium and last 100k. Email for any questions or replies but lets use common sense, i direct injected engine that is trubo charged, needs at least 91 octane(new disi engines only require 89) you ahve to run it for at least 10 minutes because a turbo disi engine or any engine for that reason runs so rich at codl start up of course its gonna load up. The hyrdocrabon(ie fuel) at the tailpipe at cold start are so high its nor even funny
CX7 Driver
Member
Well new winter is here in Chicago and we had temp at -4F to my amazement the car performs perfectly. So I don't know what changed but I drive the car the same way.
TRXSandRacer02
Member
- :
- 2000 Mazda 626 LX
If everyone can look up tsbs for other stuff why cant you all look up the tsb for pdi step 3 delivery where it says to decarbonize the spark lugs by running the engine at 4000 rpm for 3 minutes. It is for all turbo 2.3s and rx8s to prevent flooding and fouled plugs. If you ever owned an old v8 engine from the 70 or 80 that was carbureted, you would know that that is the easiest way to get your plugs clean is to hold high rpms or do highway driving
CX7 Driver
Member
Finlay found the problem all 4 coils were bad. Which is unusual but I guess not impossible.
