Slow cranking but car is fine after it starts?

[Asher1337]

Didn't know that, learnt something new

[OzCJ]

Have started to experience similar issues with slow cranking; ive done a test and had the battery on a trickle charger. Result, it cranked perfectly the first time then it struggled on the second.
Im going to check the terminals, but tending towards the prelim failure of the starter. Car has 49,500 on the ODO; will just have to hope that it keeps going till the service.

Initially I thought it was the key battery causing issues, but changed the battery and still the same issue.

[Duk]

Ignition coils, can sometimes crap themselves too.

Have you pulled out your spark plugs to check the condition???, if its not a spark problem or anything pre-spark. Then its probably a fuel related, . Could be the fuel pump relay .

Normally, you would do what you have already done, and work you way down the chain...

1. Check battery and/or terminal connection
2. Alternator.
3.Starter
3. Ignition Coil
4. Fuel Supply/pumps/
5. Relays related to Fuel pump

Judging from you scenario, i would assume the car starts better when warm, or at operating temp compared to a cold start. I'd had similar problems on other cars before, but it was vice versa to your situation,

[OzCJ]

Ignition coils, can sometimes crap themselves too.

Have you pulled out your spark plugs to check the condition???, if its not a spark problem or anything pre-spark. Then its probably a fuel related, . Could be the fuel pump relay .

Normally, you would do what you have already done, and work you way down the chain...

1. Check battery and/or terminal connection
2. Alternator.
3.Starter
3. Ignition Coil
4. Fuel Supply/pumps/
5. Relays related to Fuel pump

Judging from you scenario, i would assume the car starts better when warm, or at operating temp compared to a cold start. I'd had similar problems on other cars before, but it was vice versa to your situation,

Thanks for the reply, but the car has an extended crank before starting and its the first one after which its fine except of course if the car is off for an extended time. So I dont really know if its to do with the operating temp. I may have to call into the dealership for a diagnosis. No time to complete the checklist, but I would think its pretty lame after only 50,000k on the ODO.

[OzCJ]

OK, so the car was serviced this week, 50K and the issue mentioned to the dealership. But as usual, they couldnt fault it or the MDS didnt pickup any faults. Now Ive got 5 days of videos that prove otherwise and as I start the car leaving the service place, it cranks longer than usual. Thinking that I had lost my mind, drove home. The next morning, it starts up fine, then 10 hours later, the car cranks a lot, then kicks in eventually. Did a quick burst around the town, turned off the car, 2 hours later, same thing.

So it seems like it is a fuel system related issue, given that it cranks longer only after the car is driven. Given that it eventually starts, eliminates the batter & starter as the issue.

Could this be heat soak? While the engine is cooling its causing the fuel to expand or there is a air gap in the line somewhere? Any help anyone??

[OzCJ]

After much investigation and troubleshooting, here is the log of warranty repairs carried out till finally it was the...

1. Fuel pump assembly (within fuel tank) replaced under warranty (service centre diagnosis) - problem still there
2. HPFP replaced (part ordered from Japan) (Mazda Australia Tech diagnosis) - problem still there
3. Finally, EGR valve was found to have buildup. This was cleaned and now car is like new again

FYI, car had done around 45,000km

[Jrbris]

After much investigation and troubleshooting, here is the log of warranty repairs carried out till finally it was the...

1. Fuel pump assembly (within fuel tank) replaced under warranty (service centre diagnosis) - problem still there
2. HPFP replaced (part ordered from Japan) (Mazda Australia Tech diagnosis) - problem still there
3. Finally, EGR valve was found to have buildup. This was cleaned and now car is like new again


FYI, car had done around 45,000km

where is the EGR valve ?

[OzCJ]

where is the EGR valve ?

Its located towards the right hand bottom back of the engine (you facing the engine). Its got the plumbing to and from it. I'll post a pic when I can.