Hello, I have a problem with CX-7 USA 2007 running in ukraine (russia)
When i bought it, there was a check engine with error "Lean mixture at bank 1 when idle". It has sound like a diesel engine, a bit louder than standard direct-injection engine.
Dealer told this is because of low-quality gas. It have a big amount of sulfur in it, regardless USA gas.
I changed gas to 98 premium.
Check engine was cleared, but check engine turned on again.
Then i cleaned fuel system : filters, sprayers, shutter, changed oil and candles. Check started to shine after 70 miles.
At service they told :
1) this is VVT clutch problem. 2007 mazda VVT clutch made of weak metal, so it stire.
2) the second problem is exhaust collector padding.
Then i began to hear strange chain rustle at start. Probably because of VVT clutch.
I have changed VVT clutch. Rustle now sounds much fewer time (1/2 seconds) when engine is cold. diesel sound became much quiet. But I can still hear it when engine is hot.
I have changed exhaust pads. - turbine, collector and one more (do not remember which one). At service I have ECU reflashed to russian control program. Added 700 gr. of oil (it eat 700 grams in a 6000 miles)
However, diesel sound came back. Check engine came back in 25 miles.
One more symptom : on the idle, when engine is hot, idle rpms can fall to 600 from standard 750. Btw, after that, check engine has turned on.
I'll really appreciate any thoughts about that problem.
Thanks in advance.
Here are my sound records:
chain rustle at start
http://rstblog.com/wp-content/uploads/start.mp3
Engine sounds from inside :
http://rstblog.com/wp-content/uploads/inside.mp3
And from engine compartment
http://rstblog.com/wp-content/uploads/engine.mp3
When i bought it, there was a check engine with error "Lean mixture at bank 1 when idle". It has sound like a diesel engine, a bit louder than standard direct-injection engine.
Dealer told this is because of low-quality gas. It have a big amount of sulfur in it, regardless USA gas.
I changed gas to 98 premium.
Check engine was cleared, but check engine turned on again.
Then i cleaned fuel system : filters, sprayers, shutter, changed oil and candles. Check started to shine after 70 miles.
At service they told :
1) this is VVT clutch problem. 2007 mazda VVT clutch made of weak metal, so it stire.
2) the second problem is exhaust collector padding.
Then i began to hear strange chain rustle at start. Probably because of VVT clutch.
I have changed VVT clutch. Rustle now sounds much fewer time (1/2 seconds) when engine is cold. diesel sound became much quiet. But I can still hear it when engine is hot.
I have changed exhaust pads. - turbine, collector and one more (do not remember which one). At service I have ECU reflashed to russian control program. Added 700 gr. of oil (it eat 700 grams in a 6000 miles)
However, diesel sound came back. Check engine came back in 25 miles.
One more symptom : on the idle, when engine is hot, idle rpms can fall to 600 from standard 750. Btw, after that, check engine has turned on.
I'll really appreciate any thoughts about that problem.
Thanks in advance.
Here are my sound records:
chain rustle at start
http://rstblog.com/wp-content/uploads/start.mp3
Engine sounds from inside :
http://rstblog.com/wp-content/uploads/inside.mp3
And from engine compartment
http://rstblog.com/wp-content/uploads/engine.mp3
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