Mazda Tribute cuts off

My wife's 2001 Mazda Tribute with 128,000 miles cuts off when coasting into a stop light. She has to keep one foot on the accelerator and the other on the brake. It did this a few years ago and replacing the idle air control valve on the top of the motor solved the problem. Replacing it this time did not help. This car has never had a tuned up. It has a V6 in it. Would new plugs solve the problem? How do I replace the back 3 plugs which are under what looks like a plastic air intake manifold? Do I need a gasket or anything other than the plugs if I remove the intake manifold etc to replace the plugs? Any ideas on what the problem is and things to watch out for are appreciated. Didn't look in the manual to see if the plug gap is listed.

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How do you change the spark plugs on a 2001 mazda tribute and what gaskets etc are required?
In: Mazda Tribute [Edit]



Answer
If you have a v6 engine, you'll need a size 8 socket. First remove the three screws that hold the black cover on top being careful to not drop them. Next, you'll see the first 3 plugs with wires attached to them. These are the distributors for each plug. unplug them by squeezing the ends of the caps and pulling them off straight to the side. You will now loosen the distributor caps with the number 8 socket w/ extension and pull off the cap. You will find the spark plug under them which requires the small spark plug socket and extension. Do this one at a time with the engine cooled down otherwise it makes it difficult to unloosen them. Reverse the process to install them. Finally you'll have to undo some of the top manifold and some of the hoses to find the other 3 towards the middle of the engine closest to the firewall. You shouldn't need any gaskets as long as you are careful when pulling the top plastic manifold off. Be organized and remember where all the screws go when reinstalling the manifold and vacuum hoses back to the original areas. I did mine and took only about 15 minutes. Good luck!
wiki

Are there any codes or Malfunction indicator lights being displayed? I supposed that the EGR valve could be sticking open but it should show a code.

Are the power brakes working OK? Can you hear any hissing noise from a vacuum leak.

I had that problem on GM vehicle and after installing a fuel gauge I noticed a big drop in fuel pressure when accelerating up a hill, so I pulled the gas tank and found a lot of crud around the stocking on the pickup tube of the fuel pump. After cleaning the crud I installed a new pump with a new stocking and that fixed the problem. Pump cost $50.00.

My neighbor was watching me and said I wouldn't change that pump. I replied you're aren't doing all this work either. This vehicle would just shut off like you shutoff the ignition going down the highway, then it would restart and keep running. Hal

There's no hissing sound and the brakes work as usual. No dash lights come on other than the check engine light which has been on for a few years. My wife took it to the shop a year or so ago for the check engine light and they reset it but it popped back on in a day or two. I don't remember what they told her. I'll take it to a parts store and see if they will hook it up to a computer to see what's wrong. The car didn't cut out yesterday. Thanks for the wiki information. I didn't know about that website.

Several codes came up and the tech said the EGR valve and/or upstream oxygen sensors are gunked up. He gave me a bottle of fuel system cleaner that may clean out the carbon. If that doesn't work the next thing is to replace the EGR valve and then the upstream oxygen sensors. I replaced the sparkplugs today. Getting the intake manifold off wasn't too bad. There are several hoses to unhook, a few electrical connections, the throttle linkage, the EGR valve bracket, and the air intake hose. It still idled rough as before.