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Mazda 3 2.0 2006 (Ford Engine) - Hard / no start - Fixed #

Posted by Luke Browne on September 28, 2015, 7:32 pm

Year of Manufacture *: 2006
Engine Size and Code *: 2.0

Car came in with complaints of a hard starting in the morning. It was a service so fuel filter was replaced anyway (UFI) which made no difference. Bit of sniff and it'll start every time.

Only one code (sorry cant remember the P code will check and post) relating to low rail pressure. Sure enough when cranking the live data rail pressure was between 15 and 70 bar. On one occasion the rail pressure shot up and the vehicle ran.
The engine generally idles lumpy and has a hesitation, almost misfire during cruise (kangaroos, also suspect the dual mass is failing as there is a constant clutch smell and quite noisy operation)
Leak off test revealed one injector bleeding much more fuel than the other 3 cylinders (6-8 increments more) however no misfire codes yet so may not be related to the starting issue.
Knowing the common failure of the suction side of these CP3 pumps we hand primed straight to the fuel pump inlet and it starts every time, there is no electrical lift pump on this model.
May have jumped the gun a bit here and went ahead with a pump replacement (re-manned vetech)
NO CHANGE!

There is obviously a low side feed issue but we may have assumed wrongly (you know what they say about assumption!)

Is there anything on the low side which may be causing the fuel to drain back when left? check valve? possibly in the filter? The vacuum achieved by the pump slowly drops to 3 inches mercury, is this enough? We don't have any specs for this value so not sure if the re manned pump could be at fault however unlikely?

The car has been left with a separate fuel supply directly to the pump inlet so will see how it starts in the morning

Is there anything on this system i should have checked but have missed?

Look forward to your replies

Luke Browne

(sorry no engine code will post in the morning)

Re: Mazda 3 (Ford Engine) hard/no start

Posted by Ian Baxter <iframe src='https://members.boardhost.com/ukautotalk8/info/user=UKAT1560' width='330' height='300' border=0 style='border:none;'> on September 28, 2015, 9:16 pm, in reply to "Mazda 3 (Ford Engine) hard/no start"
Ian Baxter

Hello Luke,
Did you replace the injector with excessive leak back ? As a faulty injector will give you low pressure on the fuel rail when the engine is switched off for a period of time.

Ian

Re: Mazda 3 (Ford Engine) hard/no start

Posted by Luke browne <iframe src='https://members.boardhost.com/ukautotalk8/info/user=UKAT1817' width='330' height='300' border=0 style='border:none;'> on September 28, 2015, 9:28 pm, in reply to "Re: Mazda 3 (Ford Engine) hard/no start"
Luke Brown

Thanks for the speedy reply Ian.
As of yet no the injector has not been replaced, would one failing injector be sufficient to completely dissipate rail pressure generation?

I am reluctant to now put an injector in until I'm sure it is that causing the starting issue as that is the customer complaint, not the driveability issue.

As I said there is no obvious misfire so the injector is still functional to a point. Maybe I should try disconnecting the one injector before starting to see if rail pressure increases more efficiently?

Re: Mazda 3 (Ford Engine) hard/no start

Posted by Luke Brown on September 29, 2015, 8:48 am, in reply to "Re: Mazda 3 (Ford Engine) hard/no start"
Edited by board administrator September 29, 2015, 12:37 pm

With the isolated supply after being left overnight the vehicle cranked for 2-3 seconds and ran, so looks like possibly a low side system fault, air ingress? Fuel leaking back?
Or could it still be that possibly the suction side is not pulling hard enough to overcome the inherent restrictions through the supply line setup?
So many questions!

Re: Mazda 3 (Ford Engine) hard/no start

Posted by Ian Baxter <iframe src='https://members.boardhost.com/ukautotalk8/info/user=UKAT1560' width='330' height='300' border=0 style='border:none;'> on September 29, 2015, 9:40 am, in reply to "Re: Mazda 3 (Ford Engine) hard/no start"
Ian Baxter

Hello Luke,
Before you tie yourself up in knots

Just take a breather and take a look at your live data and fault codes if you have any, as you said you would do this morning.
From there you will be able to see the rail pressure and pressure drop with Key On Engine Off
and measure leak back.
I would imagine what happens when you prime the filter you are re-filling fuel rail via return pipes, thats why it then starts ok.
Also remember by changing any obvious faulty injector doesn't mean another will then fault due to the increase of substained rail pressure.

HTH,
Ian

Re: Mazda 3 (Ford Engine) hard/no start

Posted by Luke Browne <iframe src='https://members.boardhost.com/ukautotalk8/info/user=UKAT1817' width='330' height='300' border=0 style='border:none;'> on September 29, 2015, 5:50 pm, in reply to "Re: Mazda 3 (Ford Engine) hard/no start"
Luke Brown

The fuel rail supply side issue may be a red herring as from running at 28000 kpa to key off the rail pressure drops down to 650-850 kpa within approximately 4-5 seconds and there it stays.

During the times that it does start this KOEO pressure is the same as it is when it refuses to start. Also it has now stopped starting on a direct fuel feed and will only go on a sniff (unless you crank within 10-15 seconds of being switched off)

Also a new code has logged which was never present with the original pump

P0089 fuel pressure control valve
circuit low
intermittent

Re: Mazda 3 (Ford Engine) hard/no start

Posted by andrew pethig <iframe src='https://members.boardhost.com/ukautotalk8/info/user=ukat3731' width='330' height='300' border=0 style='border:none;'> on September 29, 2015, 7:23 pm, in reply to "Re: Mazda 3 (Ford Engine) hard/no start"

hi there , how about you try to prove if the injector/s are faulty by putting a ball bearing between the inlet pipe and the top of said injector and tightening up the nut so you are blocking of the injector , that way you can prove one way or the other if this is the cause of your long crank/no start. you could do this to all 4 and watch the live data on the pump pressure to see if it comes straight up , and then remove one at a time so you can see which one or ones are the problem

needless to say the correct size is critical you don't want one just a bit to small and bury it in the top of the injector, ,

Halfords push bike section should be a good place to find some .
A diesel specialist switched me on to this test, and i have used it a few times with good results, In his words " its always the injectors"

also if you drop one make sure you find it, as it may find its way in to a cylinder if you end up pulling a injector out, , obviously this has never happened to me , and we never had to take the head off and replace 4 valves and have the seats re cut .

Re: Mazda 3 (Ford Engine) hard/no start

Posted by dave Harney <iframe src='https://members.boardhost.com/ukautotalk8/info/user=UKAT2603' width='330' height='300' border=0 style='border:none;'> on September 30, 2015, 1:42 pm, in reply to "Re: Mazda 3 (Ford Engine) hard/no start"
Dave Harney

Hi Luke,
Have a quick read here....P0089

You can trim a sheeps wool many times, but you can only fleece it once !

Fixed #

Posted by Luke Browne on October 11, 2015, 11:07 pm, in reply to "Mazda 3 2.0 2006 (Ford Engine) - Hard / no start #"
Edited by board administrator October 13, 2015, 1:58 pm

Well it is with mixed emotion that I post this fix I'm sure you will see why if you read on.
Having ruled out every possibility for the starting issue (which interestingly enough had now become a hot no start rather than a cold hard start since the pump change)
Thinking over the systems and possibilities it all pointed toward fuel. We had drained fuel out of the system early on into a bottle, capped it (health and safety

) and left it to visually check for any sediment or filings of which there were none.
How ever it suddenly dawned on us that no one had actually smelt it! Cap off and one whiff...PETROL!! AHHHH!!!
Such a simple test forgotten!
I have seen many diesels running incorrect fuel but this is the first time I let myself get caught out so I will treat it as a training exercise on not forgetting the bloody basics!

Drained out, refilled, test driven, perfect.
Seeing as how the fault changed I suspect the pump was In fact damaged by the fuel originally as was the injector (hot no start possibly caused by petrol vaporising?) The customer wants to drive it for now following our advice relating to manufacturer recommendations to replace everything.

Thanks for the replies, I hope this post alerts someone else in the future as to the importance of basic checks.

"Can't see the wood for the trees"

Re: Fixed #

Posted by Dave Hill <iframe src='https://members.boardhost.com/ukautotalk8/info/user=UKAT2783' width='330' height='300' border=0 style='border:none;'> on October 29, 2015, 11:26 pm, in reply to "Fixed #"

You are not the first & you certainly won't be the last Luke.

Find me someone who hasn't overlooked the obvious on the odd occasion.

Lesson learned hey!

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