Yet another problem...

Adam fc · November 25, 2009, 10:46:49 AM

Hi,recently my fc has been a right bitch to start.

At first i thought it was down to the car simply flooding itself,so i went throught the steps of un flooding it to no success.

As i turn the key i can hear the car fire up so its not flooding.It will take me anything from 5 - 10 try\'s to get her running.

Whilst having a fiddle to see if it was the imobaliser cutting the ignition after start up i found out that once u have it running and you turn it off with the key it won\'t start again.

But if you remove the imobaliser with the engine running (sounds bad i know) it will eventually cut out after a few seconds.Once i have done this she starts on the key everytime.

It will also start if i remove the fuel pump egi fuse to stop the engine just not on the key.

Im under the impression that i may have a leaking injector,weak cranking speed,poor compression.

Ive heard that the voltage to the coils on most ignitions is higher during cranking and then drops down to idle speed voltage?

Also if i turn it off on the key and i go through the de flooding proceedure before i make any attempt to start it she fires up fine.

So im guessing theres is fuel leaking into the chambers after i turn it off??

An injector lost its spring pressure and leaking fuel fom the pressurised fuel line after shut off?? but she runs fine once running lol.

Any help would be ace:D

dthebuk · November 25, 2009, 11:47:32 AM

so if you take the fuse out, crank, whack it back in and crank again it will start first time?

and if you turn it off again (once warm) and try to start it straight away it still wont start?

im not too knowledgeable on on leaking injectors, but surely it\'d have to be a pretty epic leak to flood the car so easily?

is there much of a difference when starting hot and cold?

Have you checked the spark plugs? i remember seeing a picture of one brett had to remove in a car park which looked pretty much destroyed.

personally i\'d start with plugs as they\'re the cheapest thing, but theres no harm in checking the injectors too. If it is leaking, you should look at getting it sorted sharpish, leaving fuel in the engine is not good for the water seals!

good luck, im sure someone else will be along in a minute to give more help

Adam fc · November 25, 2009, 11:53:46 AM

yeah its easyer to start once warm around 70 degree\'s, and yeah if i go through the de flood it starts first time.

just weird if i pull the imobilser out to stop it it will start again fine??

dthebuk · November 25, 2009, 11:57:40 AM

start again fine straight away? try leaving it for half an hour to an hour after turning it off that way. If it floods, it sounds like a leaking injector. You could also try reving to 3k and pulling the key out

grinder · November 25, 2009, 12:37:23 PM

to be honest - i always stopped it like you do by pulling the fob - and turn it off just when its spluttering

never flooded in 3 yrs of ownership and started first time everytime with this method

Adam fc · November 25, 2009, 06:54:37 PM

ill pull the plugs when i get a chance and see what condition they\'re in.

Just don\'t know what pulling the imobaliser out does differently to turning the key off?? does the imobaliser cut the fuel pump then??

Brett · November 25, 2009, 07:29:14 PM

Might be worth checking the cranking voltage on the battery?
I replaced the plugs about 3500 miles ago iirc (+whatever mileage you have done)
:wave

MiniMike16V · November 25, 2009, 08:15:26 PM

I have similar probs with mine sometimes. Used to get the engine revving to about 3k for a few seconds on initial start up, but with the recent cold she doesnt do it anymore. Warm starts it takes a few cranks, but if I push the throttle to the floor she usually fires up pretty quick.

Do you have problems with your idle when you first start the car? Mine stalls as the revs drop too much, but when it\'s warmed up its fine :2Rolleyes

Adam fc · November 25, 2009, 08:41:34 PM

Yeah my idle has no real pattern,it\'s just completly random.

And as for the battery I came back to the car today around 7.00pm after being away and the clock was Reading 12.00 when I had turned the car off around 9.00am this morning?? Could the battery be at fault? If so il rob the one out of my mums volvo and give that a try.

Brett · November 25, 2009, 08:46:04 PM

Looking like the battery to me...

Adam fc · November 25, 2009, 10:01:50 PM

Il see what the battery levels are like in the morning,and try another battery aswell then report back!

Adam fc · November 26, 2009, 10:40:48 AM

pulled the plugs today they seem fairly clean so they\'re not the cause.

My step father suggested that it may be down to having no back pressure,so i put the silencer bung in the tail pipe and its started first time every time today.

I was convinced it was the battery but now im not so sure.I dont see how that lack of back pressure could have done this as ive been running the exhaust for weeks now with no probs till the other day.

I dont know if im loosing compression?? it still boosts fine up to 0.8 bar and pulls like a train with the bung out.
Having the bung in sucks as it only boosts to around 0.3 bar lol

rx7pat · November 26, 2009, 10:50:36 AM

Hello mate
From what I can make out it sounds like it is flooding. My immobiliser on my old car used to cut the fuel pump electrics so I could turn the engine over but it would never start. So in theory it does a similar thing to the fuse, leaving the fuel lines without to much pressure to flood the engine.

Is the consumption higher than normal? Any after burning/popping while driving?

I would get the injectors out and tested at a mechanics to see if leaking, as they can be expensive to buy.

Spark plugs are always worth checking. If the car is turning over quite quickly battery should be good, just dont hold it too long trying to start.

Just a few thoughts

Patrick

Adam fc · November 26, 2009, 10:56:17 AM

yeah cheers for the advice,its certainly got a few people scratching theres heads at the moment.
throuble is though there are so many reasons for it doing this its just narrowing it down to a conclusion.
Its not popping or farting at all once running and is quite smooth to be honest.

Ive allso found that my turbo elbow is leaking allot so im wondering if this could be affectting it??

Im really hoping its not leaking injectors as it could be exspensive.I will admit i got caught short and ran the car quite low on fuel so im wondering if theres some ....e in the lines or injectors??

The fuel light never came on mind but im not sure its even working lol?

rx7pat · November 26, 2009, 11:18:25 AM

Never tried the stuff my self but you always got the option of high octane injector cleaner, mix with a tank of super juice. Once warm give it a good run and blast it to the red line buzz. I was once told you should hit red line at least once every few times you drive.

Also go for a drive and shut off at the key once cool take out a spark from each rotor and see if there is much of a smell of fuel.