Mazda CX-7 Engine Problems

I wouldn’t expect them to touch the transmission when replacing the turbocharger. You could have another mechanic check the work done.

There have been a number of reports of engines failing because the oil has become contaminated with diesel fuel, so you're not alone there. I would urge you to request a goodwill payment from Mazda for at least part of the cost of a new engine. As your car is eight years old and has done 120,000 km you're unlikely to get a new engine from Mazda, but I think you have a good claim for a part payment. Once the engine is replaced I would suggest you change the oil more regularly than is recommended by Mazda.

Sludge build-up is a turbocharger killer, but sludge won't build up if the car is regularly serviced and the oil is changed so it's always fresh. The problem is usually only with cars that haven't been serviced. Other seven-seaters you could look at are the Kia Sorrento, Hyundai Santa Fe, or Toyota Kluger.

Call in at your nearest Mazda dealer and have them explain it to you. Without seeing it I couldn't tell you what it is.

We contacted Mazda on your behalf and this is the response we received from their technical people: "It sounds like there is a bit of confusion as to what the light relates to as the vehicle is also equipped with a gauge to indicate Adblue Level. It sounds like the customer may be relating the light as a level indicator. The light can be an indication of a system malfunction of some type, this would need to be diagnosed which it sounds like may have occurred. Depending on the cause will dictate the parts required to be replaced. There are separate components and not all concerns require tank replacement. The comments suggesting there is a massive problem and the tank could go at any time are bit unfounded and sound like unfounded Internet chatter. Our recommendation would be to let the dealership perform the diagnosis and repair. If the repair is completed by a Mazda Dealer as a Retail Repair using Genuine parts the parts are covered by our Whole of Life Parts Warranty." It might not be an answer, but it does give you a guide to the cause, as the warning light might be an indicator of another problem.

Straight back to your dealer is where. But before you do get your facts straight and run a fuel consumption test so you know exactly what the consumption is. Now, the specs you quote are I'm guessing the official figures, if they are they not real life figures, but the results of a laboratory test done under strict conditions. You won't necessarily get the same consumption, but you should be able to get somewhere close. Based on the figures you have supplied you're not, so you have grounds to complain and ask the dealer to check the car over, even run a consumption test himself.
 

I think you have a reasonable claim against Mazda to cover part of the cost of the repair and I would approach them with that request. The compressor should normally be expected to last longer than yours has.

Neither problem would seem to be normal and I would be demanding the dealer do something about it. The black smoke would suggest it is running too rich in that first start-up phase, the rough running and stalling would suggest it is too lean once warmed up. I would certainly have it checked by the dealer.

BEFORE buying any car it is worth checking its fuel economy. Every carmaker publishes a fuel-consumption figure and that is affixed to the windscreen in new-car dealerships, which makes it easy to compare one make and model against other cars in the market. That way you can identify which ones are economical and make your decision accordingly. After that it is a case of driving to achieve the best economy.

DRIVING style has a huge impact on fuel economy and is the first thing I'd recommend any owner look at if they want to reduce their visits to the servo. Easing up on the throttle is a great way of saving on fuel, as is reading the traffic ahead, and not racing up to traffic lights when it's clear you're going to have to stop. Use some smarts and you'll reduce your car's consumption.