Starting a flooded engine! - peteH
Despite HJ advice re problems starting cars after moving them a short distance, my girlfriend started has flooded her car (Fiat Brava 1.4) again.

This is the second time she has done this. The first time a local mechanic towed the car away and diagnosed the problem as a flooded engine.

This time I have tried to solve the problem myself.Following the previous advice in this group (see below) I have removed the plugs, dried the excess petrol of on some kitchen paper, and left the plugs out (and combustion chambers open) overnight - 15hours before refitting the plugs in the car.

The plugs look ok, on the spark end, but there is a little corrosion around the nut end. possibly why the plug caps were so difficult to remove. I have replaced two of the HT leads - making sure that only one was changed at a time, so not to confuse the firing sequence.

When the car was tried again it was exactly the same. The engine turns smoothly, but does not fire at all.

Any other suggestions, before I have to get the car towed off again!

Thanks






"One of my readers has written to Charles Moore, editor of The Daily Telegraph, trying to get me fired for the advice I gave about this. But there are a couple of ways to get a flooded catalysed car started. One is to take out all the plugs and let the neat petrol in the combustion chambers evaporate away. The other is to isolate the cold start instructions from the ECU to the engine (equivalent flooring the accelerator pedal to give a flooded non-cat car maximum air to sort the mixture out by ). However, this last method could damage the cat.

HJ
"

Edited by Pugugly {P} on 26/12/2007 at 09:27

Starting a flooded engine! - percy
I had a similar problem with my 1.8 P reg Mondeo, and did all that you did. I also removed the electrical feed from the injectors and spun the engine over with the plugs out.

This helped a little, but on trying to start the engine I quickly found out that the accelerator had to be floored and held down before you turn the key... if it catches, don't over-rev it but keep the revs to 2-3000rpm for a while as the engine may not tickover and then you are back to square one!

Five minutes later when the engine had warmed up, conditions returned to normal.

I think I was lucky and didn't sustain cat damage, (the car has passed 3 MOTs since). Now there is no such thing as a quick re-shuffle of cars on the drive!

So very good luck and do bear in mind HJ's warnings.
Starting a flooded engine! - peteH
I have read about flooring the accelerator, but didnt think that it was safe to do on a car with a cat. There again, I understand that this problem is cause by a programe in the ECU designed to prevent cat damaging in the first place.
Starting a flooded engine! - Richard Hall
If the ECU is showing a fault condition (i.e. flooding) and preventing starting, I wonder what would happen if you disconnected the battery for a while. IIRC in many systems this will clear the ECU memory and it then reverts to default settings. I wouldn't have thought it would do any harm - disconnect the battery and put it on a charger for an hour, then see what happens. Perhaps someone with more detailed knowledge of electronic engine management would like to comment.

Richard Hall
bangernomics.tripod.com
Starting a flooded engine! - peteH
I tried what you suggested -i.e to floor the accelerator

The engined turned the first time (about 10-15 second)
the same on the second attempt
on the third attempt the engine started to turn over faster and faster and build up speed. It then began to fire, where I kept the revs up a little (if I tried to reduce the revs the engine sounded very rough - 3 pots?) but after a couple of mins all was fine.

From a little research on goggle, it appears that some car (ford & Vaxhall) have a program in the ECU for a flooded engine - activated by holding down the accelators. I am not sure if this applies to all cars. Maybe someone with some tech knowledge can advise.
Starting a flooded engine! - MarkL
Hi,

I owned a 1994 1.6i Mazda 323F. The instruction book stated that, if you had trouble starting it, to hold down the accelerator half way and then try again. This would, I guess, tell the ECU to use a set of default parameters - hopefully more suited to a warm engine. Never had to do it though.. Will, of course, be different for each type of car.

MarkL.
Starting a flooded engine! - jc
Ford ECU's certainly have a programme built-in where if you crank on WOT(wide open throttle) no fuel will be injected.It is spelt out in the driver's manual.When all else fails read the instructions!!!(RTFM).
Starting a flooded engine! - John S
pete

The answer seems to be to floor the throttle and keep the thing cranking until it finally runs. It's not pretty, as there's a period whist it coughs and splutters , but don't let the key go until it actually runs. Then it will run very roughly for a while until it gets warm. Once the car has warmed up somewhat it will then run normally and the next start will be OK.

The car doesn't actually detect fuel in the combustion chambers (there is no mechanism for it to do this), but drying the plugs may help it start more rapidly. The problem is that the very short run seems to leave the ECU stuck in some 'intermediate position' and until the thing runs and warms up it won't change.

Probably not the best thing for the cat, but I don't believe a garage will start it any other way.

Regards

John S
Starting a flooded engine! - IKR
My wife's 1995 1L Micra (16V) does this as well occasionally if moved from the street to the drive etc. The cure is exactly as described above. It always seems more likely to occur in winter than summer, so I wondered if it's a cold starting enrichment problem.

With this in mind, the last few times I've stopped the engine after a 30 second run, I've held the revs at about 3000 RPM for a few seconds, then cut the ignition with the accelerator held in place.

I know the manual says not to do this, but it also says not to continue cranking if it won't start.....

My logic is that the fuel flow stops as soon as you turn off the ignition, but that the engine costs on for a few more revs, pumping air through the cylinders and removing any remaining petrol.

I can't really confirm if this works (yet). What does everyone think?

Ian
Starting a flooded engine! - Dynamic Dave
My logic is that the fuel flow stops as soon as
you turn off the ignition, but that the engine costs on
for a few more revs, pumping air through the cylinders and
removing any remaining petrol.


And the petrol also washes away any remaining oil in the cylinder bores as well. So next time you start your engine, for a few seconds there is no lubrication in the bores - hence the "cold start" syndrome.
Revving the engine prior to switching off does the engine no good whatsoever.
Starting a flooded engine! - Cliff Pope
>> My logic is that the fuel flow stops as soon
as
>> you turn off the ignition, but that the engine costs
on
>> for a few more revs, pumping air through the cylinders
and
>> removing any remaining petrol.
And the petrol also washes away any remaining oil in the
cylinder bores as well. So next time you start your engine,
for a few seconds there is no lubrication in the bores
- hence the "cold start" syndrome.
Revving the engine prior to switching off does the engine no
good whatsoever.


But if Dave's theory is correct, there won't be any petrol to wash the oil off with, because the pump will have been off for a second or too. In fact logically, there would be oil NOT washed off, as would occur normally, so in fact reving ought to be beneficial.

Revving in the old days was intended to give a charge of petrol, supposedly to assist starting next time.
This was obviously harmful. But cutting off the fuel before the engine comes to rest, and giving a spray of oil from the revving con rods, sounds on the face of it like a good idea.

Is there a snag here?
Starting a flooded engine! - Dynamic Dave
But if Dave's theory is correct, there won't be any petrol
to wash the oil off with, because the pump will have
been off for a second or too.


And the spark plugs will also have been off for a second or two. So how is the petrol you've squirted into the bores going to combust?
Starting a flooded engine! - David Davies
There is a modification to the coolant temperature sensor circuit on the 16v Micra which is designed to prevent this problem happening.It is available from Nissan and is reasonably easy to fit.Ask your local dealer.
David Davies (Tune-Up Raglan)
Starting a flooded engine! - IKR
Thanks for the advice, but I'm afraid we had this modification done the first time the problem happened. It seemed to make no difference. Given my experience with Nissan dealers, you do wonder if they actually did it though...... Do you know if there's a DIY way to tell?

Referring to the earlier discussion of revving the engine as you turn off the ignition, I'd guess that the injectors stop firing as soon as you turn off the ignition key. As a result, you shouldn't get any more build up of fuel in the cylinders than normal should you? I guess it might take a couple of seconds for any fuel left over from the acceleration enrichment to be dissipated, but the cold start enrichment is probably lower at this engine speed.

I know that revving a cold engine isn't any good for it, but we're also talking about a few seconds at about 3000 RPM. How damaging is this compared with cranking a cold engine for several minutes? Don't forget that the highest loadings on a cam shaft lobe tips are at the lowest engine speeds.

Thanks

Ian
Starting a flooded engine! - THe Growler
Could this be a cold climate issue? My two vehicles are both catalysed and I frequently start and stop them for a few seconds at a time for manoeuvring. I have never had any of the problems described above, could this be because of an ambient temperature 28-34C year in year out?

I just went outside and did it again to see if I could reproduce the above (probably not very clever!) but yep they both cranked up no probs each time.

One would have thought technology would have produced the whit by now to solve such a basic problem!
Starting a flooded engine! - <0.One%
Could this be a cold climate issue? My two vehicles are
both catalysed and I frequently start and stop them for a
few seconds at a time for manoeuvring. I have never had
any of the problems described above, could this be because of
an ambient temperature 28-34C year in year out?
I just went outside and did it again to see if
I could reproduce the above (probably not very clever!) but yep
they both cranked up no probs each time.
One would have thought technology would have produced the whit by
now to solve such a basic problem!


The problem seems to be make/model/year specific, and may be ambient temperature related.

It is probably due to some software not having taken account of the fact that people sometimes only run their engine for a few seconds to drive a feet feet.
Starting a flooded engine! - jc
Always make sure your car is thoroughly warm before turning off the ignition;if you're washing the car drive it round the block before you put it away;it wwill get the water out of the seams on the body as well as making sure you're off the "start" procedure.
Starting a flooded engine! - autumnboy
I work for a Fiat importer and no matter the weather conditions, Winter and Summer, its fateful to touch the throttle when cranking the engine to start.

It will flood!.

This applies to most vehicles with ECU's, you should wait a few seconds for the electric pump, to finish getting fuel to the injector system (listen), then crank to start without touching the throttle. Read your manual it says the same thing. No matter whether its a Fiat, Alfa, Ford, Rover or even a BMW.

Its best to leave it stand a while for the fuel evaporate, other wise using full throttle will flood it again, the ECU does'nt you a have a flooded engine???. If you still have a problem with flooding, its a garage job to find why.
Starting a flooded engine! - Richard Turpin
My D reg XJ6 used to flood easily. An AA patrolman taught me the cure amd claimed it worked on most cars.
1. Get a friend to help.
2. Unplug the fuel pump fuse or relay.
3. Start the engine. It will begin to fire.
4. When it's firing, and while you are still churning, friend re connects the fuel pump.
5. Leave running till hot.
Starting a flooded engine! - John M.
My always reliable K11 Micra (Mk 2) flooded this morning, after myself letting up the clutch a little too quickly and stalling the engine. I know this is a common problem on Micra's, usually caused by starting up the engine to move the car--something I never do.

Anyway, I was rather desperate today as the starter would not fire her back up, even after leaving it seven hours and removing and drying out the plugs... no joy. I searched this forum for a solution and Google groups (very handy), and Richard's solution above is almost identical to the specific one which I found, which cured the problem:

1/ Simply remove the fuel pump fuse (located in the car's dash).
2/ Start the engine. It will fire up, burning off the excess fuel before the engine cuts out.
3/ Replace the fuse and start the engine again. It works!! (You may need to depress the accelerator a little to mantain the revs for a minute or so).

Then I recommend a good fast run to dry out the cat. Took mine on the Motorway.

HTH someone else--it really is that simple once you know how!
Starting a flooded engine! - Oz
Instead of 'removing and replace the fuse', couldn't you install an in-line switch? Both are pragmatic solutions but the latter may make it easier / save time.
Starting a flooded engine! - Daloo
I have a 1997 GMC Sierra which I could not start for 6 days. After going thru the procedure with Richard Turpin's posting, I got it going in less than 30 minutes. Oil was polluted with gas which I changed before following the procedure. It worked like magic and I want to thank the individual I mentioned. I didn't have a friend to help me so I cranked a few times after I removed the fuel pump relay fuse; reconnected, 1 crank of the key and truck purred to a start.

Edited by Daloo on 26/12/2007 at 07:13

Starting a flooded engine! - kithmo
The problem you describe more often than not is the ECU as many of the replies point out. Another possibility is tappet jacking. That is the hydraulic tappets get filled with fresh, cold, high viscosity oil and don't drain off as they would normally do when switching off a hot engine. The immediate solution is to not floor the throttle but hold it at just less than full to richen the mixture, because the valves are not closing fully you are losing compression and the richer mix will help it to fire (albeit rough). The long term solution is to switch to a low viscosity oil for the colder weather (and even in summer if it happens then), such as a 5W 30/40 or 0W 30 synthetic. It worked a treat on my Mondeo. P.S. the above method of starting is NOT good for the CAT, but may be your only option.
Starting a flooded engine! - mikej
Just in case this ever helps anyone, flooring the accelerator whilst turning the ignition is the recommended way of dealing with a flooded petrol engine in a Mazda 6. (See 'Emergency Starting' section of the owner's manual - 7-17 in my version)

I managed to flood my 2005 2l Mazda 6 this morning and this method solved the problem for me.
Starting a flooded engine! - jc2
Cat will be dry in a couple of minutes-doesn't need motorway run but it'll be good for the exhaust.
Starting a flooded engine! - Railroad.
Speaking as someone who has come across this hundreds of times on all different makes of car, and there are some that are more prone to this than others, the way to get it started is to isolate the fuel pump and crank the engine. Removing the fuel pump fuse is normally the easiest way to do this. Most engines will start this way, but it can be a bit of a juggling act. In the case of a real stubborn one you may need to remove the spark plugs, and put one small squirt of engine oil down each of the bores with an oil can. Replace the plugs after thoroughly cleaning and drying them and try to start it.

A previous poster is correct by saying that the excess fuel washes the oil off the cylinder bores, which then results in a loss of compression. You'd be easily forgiven for thinking at first that the cambelt had broken......
Starting a flooded engine! - bill_gensheet
First, thanks for the advice. Car now started, resolved to always push it around in future, neighbourhood now smelly/foggy ;-)

I would add another way to stop the fuel, pulling the plug out of the 'Ive crashed' fuel isolation switch. Mine (1996 Rover216) is simply in line with the fuel pump and nicely accessible.

That done it ran for a few seconds as it dried out and therefore verified the rest of the system. Another 30 seconds of intermittent dry/open throttle before putting the fuel back on and it fired up if a bit reluctantly.

Bill
 

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