We don't see too many Mazda's in the workshop other than for routine servicing and tuning, they just seem to be put together much better for reliability than a lot of other cars. The Mazda 323 that came in recently though was the exception to the rule. Once started in the morning it would carry on all day long running and starting without any problem until the next morning. Then it would take about 5 minutes of cranking and cursing to get it started, if left for two days the battery would go flat and it would have to be towed to get it started. Tuning the car uncovered nothing untoward, we paid special attention to the operation of parts that could cause cold starting problems such as poor Ignition output on cranking, malfunctioning autochoke mechanism, starter motor and battery. Still nothing put it's hand up and said "IT'S ME", so we had to keep the car overnight to see what was going on the next morning. Sure enough the Mazda didn't want to start despite having plenty of sparks at the spark plugs at the right time, so the answer had to be on the fuelling side. the Autochoke was working OK, but as soon as an egg cup full of petrol was poured down the throat of the carburettor the engine sprang straight into life. The problem then had to be a lack of petrol from the carburettor on cold cranking. The carburettor was stripped down to see if the fault lay here, but no fault was found. The petrol pump was checked next - while it was good on output pressure it was lower than normal on suction from the petrol tank. This transpired to be the problem - a new petrol pump was the cure, it wouldn't suck enough petrol quickly enough from the petrol tank to replace the amount lost from the carburettor float chamber during the night.

Hessitation, power loss. This type of problem can be one of the most time consuming faults to find because the problem often is only slight and the fault only shows up when the car is being driven under load.

One of the most commen causes of this is fouled or sticking injectors that can be reconditioned at less than tenth the price of a new set. For more information on injector servicing click on injector.