Hi Scotty,
I have been a fan of your videos, it has been very useful and have lots of experiences with cars. I have a question i would like to ask.
I have a Mazda 3 2017, BN model, Sedan, current mileage of 37000km. I have been experiencing random rough start, this usually happens during warm start and its random; not always happen. I have sent my car servicing regularly at 10,000km interval, changed new battery and check spark plug and it all looks good. There is no OBD error codes as well.
The video is posted to my youtube channel, https://youtu.be/vaRhiuPbWT8 .
I would hope to hear on your advice on this issue as it has been bugging me for quite some time now. It would be much more better if it could be presented in your youtube channel.
am referring to the starter knocking.. like the crank is not smooth as the first. is there any cause for concern?
Thank you and looking forward to hearing from you soon!
Regards,
kracie17
Well when they're hard to start when they're warm they generally means to fuel injectors might be dripping too much gas they might need cleaning or replacing. A cold engine needs extra gas to start but a warm engine if it is too much gas will be very hard to start because it's flooding itself out
Hi Scotty,
Thank you for your reply! Can i check, will there be any CEL or OBD error code appearing for fuel injector error system?
Not necessarily.
At your 40,000 kms service, ask for your mechanic to pressure clean the fuel injectors and see what happens.
Also, ask them to look at live data and maybe clean the MAF sensor too.
Hi InThrustWeTrust, thank you for your reply! will do the pressure clean and check the MAF sensor during my next servicing. however, i opened up and checked my MAF sensor, there is no dirt buildup though.. but still will take a look.
No worries. Yeah, check if it’s reading the correct airflow data at idle.
Curious, my car has traveled 37000km so far, the fuel injectors are already clogged so badly? i also have now and then use addictive every time i pump petrol. i use the STP complete fuel system cleaner; not everytime i pump. perhaps can say about 7 pumps then i use the addictive. it doesnt work as well?
Exactly, it shouldn’t be. A good mechanic with a fancy scan tool should be able to tell with it. The STP cleaner is a good one.
Hi InThrustWeTrust, i have gotten my mechanic to check, he says the values seems to be all normal, no abnormalities. whats the next step to take?
Check all your vacuum lines. Does your engine have GDI? If it does, check the high pressure fuel pump too. When you say ‘rough start’, you mean it’s idling rough yes? Or is it hard to start?
Hi, sorry what do you mean by GDI? you meant gasoline direct injection? im afraid i wont know this for sure. i have provided the 2 video comparison for your reference. one is the rough start and the other is the normal start. what i meant by rough start, is the rough crank. im afraid i cant explain much in words. idling is normal, starting is okay. just that it feels weird. perhaps my video below may explain further.
normal crank
https://youtu.be/JVrY3NDG-lE
rough crank.
https://youtu.be/vaRhiuPbWT8
Just watched both the videos multiple times back to back. Are you referring to the starter knocking while cranking the engine? Or the sound after the engine has started? And yes, I was asking about gasoline direct injection. The high pressure pump is known to be noisy when in operation.
am referring to the starter knocking.. like the crank is not smooth as the first. is there any cause for concern?
Ohh, yeah I wouldn’t worry too much about that if your cranking isn’t affected at all. Does your car have engine stop-start technology (when stopped at red lights)?
im not sure if it will damage my engine over time.. due to the abnormal crank. may i seek your opinion after watching the 2 clips, do you notice anything strange or abnormal? yes my car does have the start stop feature but i have disabled it.
The engine once running, doesn’t sound abnormal, in my opinion. You can try temporarily swapping the starter with a known good one and check if the problem still persists. Good thinking disabling the start stop feature.
Hmm i did have a starter motor replaced by the authorised dealer as well. the issue still persist.
Oh okay, in that case try to find a specialist Mazda independent mechanic in your area and have them diagnose it. If they can’t, you may have to wait till the problem gets worse.
Oh, actually i have done so. i have visited mazda dealer, they changed for me the starter motor. they told me this is normal operation but i do not find it so cuz sometimes you know, they like to smoke users.. however, am unable to replicate this issue consistently. but something is telling me this isnt normal operation as i used to own the previous mazda 3 model, and none of this happens although its with new tech.