How to get to the CX-9 spark plugs

I notice the spark plug on the firewall side of the engine had an intake on top of the spark plugs. How do you get to those plugs?
 

Davicho

"The One And Only"
V
ZoomZoom
You need to remove upper intake plenum to get to the spark plugs, which surprisingly have to be replaced every 60K, perhaps more often in some cases. Also, since you are removing the upper intake plenum, you need to replace the 3 (8-shaped) gaskets between the plenum and the intake manifold. Not very difficult, just time consuming, also if you are not mechanically inclined, pay someone to do it. if you connect something back in the wrong port, you will throw a DTC and engine light will come on...Good luck!
 
Davicho, do you know the part number for those gaskets? Is there an instruction out there for removing all the right parts...etc.
 

Davicho

"The One And Only"
V
ZoomZoom
My CX-9 is a 2007, so it came with the Duratec35, and since I work for Ford (among other car lines, none being Mazda) I simply used Ford parts. I am not sure if 2008 and newer CX-9s with the 3.7L has a different intake plenum design, but if not these are the part numbers I used:

Qty. 3 - 7T4Z-9H486-DA (intake plenum gaskets)
Qty. 6 - AYFS-22F-M (or Motorcraft #SP-411) (spark plugs)
 
V
'08 CX-9 Sport AWD
My CX-9 is a 2007, so it came with the Duratec35, and since I work for Ford (among other car lines, none being Mazda) I simply used Ford parts. I am not sure if 2008 and newer CX-9s with the 3.7L has a different intake plenum design, but if not these are the part numbers I used:

Qty. 3 - 7T4Z-9H486-DA (intake plenum gaskets)
Qty. 6 - AYFS-22F-M (or Motorcraft #SP-411) (spark plugs)
I purchased the gaskets for my 2008 CX-9 yesterday. Mazda uses a different part number than Ford, but the part IS the same.
The MAZDA P/N for the gaskets is: CY01-13-135
On the package, in much smaller type, is the same Ford P/N that Davicho mentions above. So, apparently, the same gaskets are used, even between the 3.5L and 3.7L engines.

*Be aware that I had to call 6 Mazda dealers before I found one that had these gaskets in-stock. And the Parts guy told me that the only reason they had them was because someone had ordered them back in March and apparently never used them. He said that they are NOT a Stock item....which is the same response I got from the other dealerships too. I suppose when more CX-9 owners come up in mileage to where they want / need their plugs replaced, maybe they'll become a stock item.
Just wanted to mention it in case anyone plans to change their plugs and thinks they will be able to get the gaskets the same day - they will likely need to be ordered.

***BIG Thanks to Davicho for his insight on replacing the plugs!!!
 

Davicho

"The One And Only"
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ZoomZoom
Procedure to Replace Spark Plugs

Removal of Intake Plenum:

1. Remove the air cleaner outlet pipe.
2. Disconnect the throttle body electrical connector.
3. Disconnect the evaporative emissions (EVAP) tube from the intake manifold.
4. Disconnect the brake booster vacuum hose from the intake manifold.
5. Disconnect the positive crankcase ventilation (PCV) tube from the PCV valve.
6. Disconnect the PCV fitting electrical connector.
7. Detach the wiring harness retainers from the upper intake manifold.
8. Remove the 2 upper intake manifold support bracket bolts.
9. Remove the 6 bolts and remove the upper intake manifold.
10. Remove and discard the gaskets.

Removal of Spark Plugs:

1. Disconnect the 6 ignition coil-on-plug electrical connectors.
NOTE: When removing the ignition coil-on-plugs, a slight twisting motion will break the seal and ease removal.
2. Remove the 6 bolts and the 6 ignition coil-on-plugs.
NOTICE: Only use hand tools when removing or installing the spark plugs or damage can occur to the cylinder head or spark plug.
NOTE: Use compressed air to remove any foreign material in the spark plug well before removing the spark plugs.
3. Remove the 6 spark plugs.


Installation of Spark Plugs:

1. Install the 6 spark plugs. Tighten to 15 Nm (133 lb-in).
NOTE: Apply a small amount of dielectric grease to the inside of the ignition coil-on-plug boots before attaching to the spark plugs.
2. Install the 6 ignition coil-on-plugs and the 6 bolts.
Tighten to 7 Nm (62 lb-in).
3. Connect the 6 ignition coil-on-plug electrical connectors.


Installation of Intake Plenum:

1. Using new gaskets (no need for adhesive, just make sure they are seated correctly), install the upper intake manifold and the 6 bolts.
2. Tighten in the sequence (Middle front, middle rear, passenger rear, passenger front, driver front, driver rear) to 10 Nm (89 lb-in).
3. Install the 2 upper intake manifold support bracket bolts. Tighten to 10 Nm (89 lb-in).
4. Attach the wiring harness retainers to the upper intake manifold.
5. Connect the PCV fitting electrical connector.
6. Connect the PCV tube to the PCV valve.
7. Connect the brake booster vacuum hose to the intake manifold.
8. Connect the EVAP tube to the intake manifold.
9. Connect the throttle body electrical connector.
10. Install the air cleaner outlet pipe.

Hope this helps you!
 
V
'08 CX-9 Sport AWD
Please note above that the torque settings above are in "lb inches", not "lb ft", but they can be easily converted. Didn't want anyone to read that procedure and not catch the unit of measurement and WAY over-torque things.
 
V
2007 Mazda CX-9 Touring
How do you remove the plastic engine cover on the cx-9? I have the 2007 model with the 3.5 litre engine.
 
V
2007 Mazda CX-9 Touring
Davicho question. I checked with rockauto and autozone. They list the motorcraft sp 469 instead of the one you listed. Is there any difference or does the 469 work as well.
 
V
2007 Mazda CX-9 Touring
I just checked on line by googling the number you gave. They list that plug for a 2.0 ford engine? I am confused.
 
V
2007 Mazda CX-9 Grand Touring
If you arent having a problem, I wouldnt worry too much about changing the plugs, I have 70000 miles, and the stock platinum plugs looked fine, also if you are able to just lift the upper intake off you probably wont need to replace the intake gaskets, they were just fine, and looked exactly like the new ones I put in, overall I continued the job since I started it, but seems like it was a big waste of time and money for right now, maybe at 100000 miles would be a better time to do it. Also it says above to disconnect the pcv electrical connection, if you do change the plugs watch out for it, especially if you dont know where it is, its on the backside of the upper intake and if you arent careful could possibly break that thing. If you are not an experienced mech, I wouldnt try this job, just take the car in, if they break something they fix it, if you break something you pay to have it fixed. The plastic cover just lifts off after you take the oil filler cap off as well, if the guy above hasnt figured that out already.
 
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V
Mazda CX-9 Sport
Davicho - This was big, Thanks!

New to site -> Information seems awesome!

Where were you able to access information such as torque settings, etc for future reference on other work I'm Performing. Also, what resource would you recomend besides the dealer on the gaskets and other parts?





Removal of Intake Plenum:

1. Remove the air cleaner outlet pipe.
2. Disconnect the throttle body electrical connector.
3. Disconnect the evaporative emissions (EVAP) tube from the intake manifold.
4. Disconnect the brake booster vacuum hose from the intake manifold.
5. Disconnect the positive crankcase ventilation (PCV) tube from the PCV valve.
6. Disconnect the PCV fitting electrical connector.
7. Detach the wiring harness retainers from the upper intake manifold.
8. Remove the 2 upper intake manifold support bracket bolts.
9. Remove the 6 bolts and remove the upper intake manifold.
10. Remove and discard the gaskets.

Removal of Spark Plugs:

1. Disconnect the 6 ignition coil-on-plug electrical connectors.
NOTE: When removing the ignition coil-on-plugs, a slight twisting motion will break the seal and ease removal.
2. Remove the 6 bolts and the 6 ignition coil-on-plugs.
NOTICE: Only use hand tools when removing or installing the spark plugs or damage can occur to the cylinder head or spark plug.
NOTE: Use compressed air to remove any foreign material in the spark plug well before removing the spark plugs.
3. Remove the 6 spark plugs.


Installation of Spark Plugs:

1. Install the 6 spark plugs. Tighten to 15 Nm (133 lb-in).
NOTE: Apply a small amount of dielectric grease to the inside of the ignition coil-on-plug boots before attaching to the spark plugs.
2. Install the 6 ignition coil-on-plugs and the 6 bolts.
Tighten to 7 Nm (62 lb-in).
3. Connect the 6 ignition coil-on-plug electrical connectors.


Installation of Intake Plenum:

1. Using new gaskets (no need for adhesive, just make sure they are seated correctly), install the upper intake manifold and the 6 bolts.
2. Tighten in the sequence (Middle front, middle rear, passenger rear, passenger front, driver front, driver rear) to 10 Nm (89 lb-in).
3. Install the 2 upper intake manifold support bracket bolts. Tighten to 10 Nm (89 lb-in).
4. Attach the wiring harness retainers to the upper intake manifold.
5. Connect the PCV fitting electrical connector.
6. Connect the PCV tube to the PCV valve.
7. Connect the brake booster vacuum hose to the intake manifold.
8. Connect the EVAP tube to the intake manifold.
9. Connect the throttle body electrical connector.
10. Install the air cleaner outlet pipe.

Hope this helps you!
 

Pootie Tang

Certifiable
Thought I would add my experience here. Just did them on my 2008.

Thanks for the info thus far. It's helped me move through the job.

Here are my tips:

1. The Motorcraft plugs DO NOT COME PRE-GAPPED. You must gap them to .051" - .057". I used .055". DO NOT use the electrode tip to pry against.
2. My car had 80K on it and definitely needed the plugs changed. The gaps had eroded to about .070"


3. I have read that some say you can reuse the green gaskets. Mine looked good but compared to the new ones, they were not very flexible and felt "dry" and hard. These should be replaced.
4. This job is a bit of a PITA, buit with some clever hose removal, it's not so bad. BLOW the engine and crevices out with compressed air prior to diving in. Removing the plenum is fussy and hangs up on numerous things. This can knock debris into the intake runners.
5. The two back hoses are the toughest. For the passenger side one, I waited until I had the plenum lifted off a bit and could get to it. I pulled it off from the valve cover end. Slight twist and off it comes. Right next to it is an electrical connector that is almost hidden. You can remove it "blind" if you try.
6. For the hose with the "fishnet" behind the throttle body, I traced it to behind the battery. I removed the battery and then removed the bracket shown (in red circles). Pretty easy. I could then get at the hose end there and fished it around and removed it with the plenum.




7. I needed to remove the valve directly above the throttle body for clearance (green circle).
8. The plenum is a tight fit but comes out straight towards you with a little fussing.
9. Be VERY careful not to drop anything into the intake runners. I placed a towel over them once I could.
10. I agree with the warning not to use power tools on the plugs themselves. This seems like an engine that is not very tolerant of brutality.
11. The coils were a bit stuck. I pried carefully from under and to the right of the screw mount hole to ensure I was prying against the full thickness of the bracket and they popped up with a little effort.

I can only imagine a careless mechanic doing this job. Small washer down the plenum or dirt/debris. It's also easy to lean on the air conditioning hose on the passenger side. Too much leaning and this thing is going to leak really soon. Easy to "break" the thin wires of the numerous electrical connectors. Each one of these will not manifest itself right away, but will almost certainly result in frustration and difficult troubleshooting to come- all without the culprit to blame and your time and money as the casualty. I strongly recommend participating in watching your mechanic do this job. If they mind, find a different mechanic. In all, took me about 2.5 hours, working steadily. 2 hours I suppose the second time around.
 
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V
2007 Mazda CX-9
GOD BLESS THIS FORUM!! Pootie Tang your pictures and descriptions walked me through this task with ease!!! I'm no mechanic, but am mechanically inclined, it did take me about 4 hours to complete the task, only because of interruptions and what not....I'm positive next time it won't take nearly as long.
 
V
Mazda CX9 Grandtouring 2008
I took mine to local Sears auto but when I got my car back everytime I applied gas the car started shaking, what you think they did wrong
 
V
Mazda CX9 Grandtouring 2008
I took my car to Sears Auto, but when I got it back every time I press on the gas the car would shaked, liked it's not getting enough gas. What you think they possibly did wrong?
 
V
Mazda CX-9 Sport
I took my car to Sears Auto, but when I got it back every time I press on the gas the car would shaked, liked it's not getting enough gas. What you think they possibly did wrong?
Most likely they screwed something up :)

Probably loose spark plug connections. Hopefully not a broken spark plug that they just ignored hoping you won't notice.

I would go back ASAP since they would try to blame it on something else.

And try to find yourself a decent mechanic, usually the service at sears, Pepboys and such is not that great.
 

Pootie Tang

Certifiable
SEARS!? I'll bet it is a vacuum leak. The might have done the intake plenum gasket wrong, cracked it, left a hose off etc. And YES, they will try to blame it on coincidence.
 

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