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Hi, I have a 2001 Mazda tribute, manual, 2 litre.

Intermittently there is loss of power and then the car surges back to full power this can repeat off and on for sometime, it doesn't greatly affect performance but it does affect fuel consumption.

At the same time there is loss of power to the speedo so the speedo dies, then bounces up again, a few times. If the speedo dies for any length of time it shows as a 'loss of power' on the computer read out but gives no reason. The engine warning light comes on.

My mechanic has been unable to identify the problem.

I have become aware that I can create the problem by riding the clutch. Ok so I know clutch should not be ridden BUT at times like when holding a car on a hill -it is manual - or when reversing in a tight area, the clutch is riden.

Any suggestions?

I am going to go and get the analytics computer put on it, then go and ride the clutch to create the problem and HOPE that shows up something.

Chris

You should try avoid riding the clutch and have the mechanic connect the computer to see what fault codes are present. If the engine warning light comes on there will normally be a stored fault code. Once the technician has a fault code it will be easier to trace the cause. It sounds like there is a bad electrical contact or an electrical sensor fault. Another option is to take the vehicle to a Mazda dealer as they might have come across this type of fault in the past.

The fault code was just loss of power.

Mostly I can avoid riding the clutch, but hill starts and reversing necessitates it. Remember it is a manual.

My mechanic has rung mazda, they were unable to help.

It could be the speedometer speed sensor fault. The sensor is located on the gearbox. Have your mechanic test the sensor and electrical connections.

If the injection system doesn't receive a speed signal it can also cause this problem.

Let me know what he finds.

Thanks I will get them to try that. We have wondered about the fuel injection. Sometimes it idles really rough too, and can stall coming up to an intersection, the rev counter bounces. But the two faults don't always happen together.

I would love to ditch it and buy another one but that is not an option right now.

Other than this it is a great car, love the 4x4 option.

Chris

Looked online, is the speed sensor and the ABS sensor the same? If so, we have already replaced that.

Chris

An ABS speed sensor is the one that is located by the wheels and sends a speed signal to the ABS computer. A speedometer sensor that sits on top of the transmission feeds the speedometer the vehicles km/h speed it is travelling. Most new model vehicles will use the ABS speed reference for the speedometer but earlier vehicles used a separate sensor on top of the gearbox even though it has ABS. Ask your mechanic to confirm if it has a separate speedo sensor located on top of the gearbox.