NON STARTING 350i

[GRIFFONMARK]

It had to happen, the wedge has finally let me down, but why why why on the first sunny day for 20 years. It has run perfectly, never even a slight misfire, since the day I got it until I went on holiday. It had to be left outside for 3 weeks when it rained every day. Now it sulks and refuses point blank to fire. Not even a gnat fart. Fully charged battery spins it over so fast it doesn't really need an engine (except for noise output). The plugs are wet with fuel and there is a spark. It's even a sunny day. Cleaning the plugs makes no difference whatsoever. The last time I used it was the day before my holiday, to move it out of the garage onto the drive, when everything seemed normal. Any ideas?

[honestjohntoo]

GRIFFONMARK said:

The plugs are wet with fuel and there is a spark.

Spark! Where? At the king lead or at the plugs.

If only at the king lead, could be moisture from the wet weather inside the dissy cap preventing plugs from sparking.

If sparks at the plugs, then the fuel/air mixture is too rich to ignite.

Look at all the components that might cause overfueling.

Temp sensor, Throt pot, Pressure regulator, Cold start injector and ECU.

Comprehensive Tests for all these and lots more, from the following index.

http://www.vintagemodelairplane.com/pages/Rover_Te...

[dwgriffith]

Flapper or hotwire injection ?

[GRIFFONMARK]

Thanks for all the advice so far. It's a flapper. I have a spark at no.2 spark plug (and I assume at all the others) and as the plugs are so wet I assume there is overfuelling. What I can't understand is why there is no attempt to fire whatsoever. Even with very badly overfuelling engines in the past i have always found the engine made some attempt to start. I might introduce an air leak and see what happens. Regards, Mark

[GRIFFONMARK]

I forgot to mention, its bloody sunny again. The only sun for as long as I can remember and the Tasminger won't start!

[Roger McLittriss]

Pull off half the injector plugs - if it's overfuelling that will cut down the amount of juice in the inlet manifold.
Also disconnect the cold start.
Even if you have a spark it may not be a good spark - if it's orangey rather than deep blue you might have an ingnition problem.

[dwgriffith]

Had the exact same on my first 350i once, it was simply flooded. After 2 days of trying everything I followed the standard range rover flooded engine start procedure. Remove the intake hose at the plenum and mop up any fuel in the intake, on mine I wedged the butterfly open for an hour or so to try and evaporate some of the fuel away. I also dis-connected the cold start injector before trying to start the engine again (and left it disconnected). Replace inlet hose and crank the engine with the throttle OPEN. After a couple of 10 second attempts mine started up and ran without any further issues.

[jmorgan]

Whatever the problem, flooded plugs can be a mare. I really had to clean mine up including baking in a low oven (usual disclaimer if they get knackered). I carry the last good set that were changed due to use just in case. Flooding that one time caused me no end of issues finally solved by new plugs.

[GRIFFONMARK]

Thanks to everyone, I'm getting some good advice here. I checked out the cold start injector and that is working OK but I can't believe the amount of fuel it chucks out. My engine stinks of fuel and is obviously totally flooded. I'll try removal of the intake pipe and clean the plugs again to see if that helps. The spark is orange though, and while I was checking everything I found the HT lead from the coil had split at the dissy. Maybe that's what caused it to fail to fire and then flood. I'll get a new lead tomorrow and probably get it running only to find today was the last sunny day of the year. Fingers crossed. Regards, Mark

[dickymint]

If it's flooded - just remove the fuel pump fuse and crank it over untill it fires up. Works every time on my SEAC.

[adam quantrill]

Deffo agree there - as the pressure goes down the injectors push less and less fuel in, and it's a classic symtom of the engine temp sensor going duff, if it works OK under intermittent fuel fuse usage.

[TVRleigh_BBWR]

everyone I know, disconnects the cold start injector, its just not get cold enough in the UK to need it.
will help stop you flooding it.

[Bodmin]

If it has had that much fuel pumped into the cylinders you may have inadvertantly washed the oil off the bores & lost compression.

Remove all the plugs, I know some are a bds, & put about 5-10cc of oil in each cylinder, cover the plug holes with cloth or paper towl & crank the engine for a few seconds....this pushes out any excess oil...this is IMPORTANT or you could hydralock the engine...., refit the plugs & restart. I have had this happen on a 350i I used to own & on the 400SE I still own.

Make sure you are in a well ventilated area & if the neighbours have got there washing out give them a warning because if it does fire up & you will not be able to see anything at the back of your car for a few minutes

Bodders

Edited by Bodmin on Tuesday 16th September 18:39

Edited by Bodmin on Tuesday 16th September 18:40

[GRIFFONMARK]

Thanks to everyone again. I tried with the fuel pump fuse removed but no change. However, I have been concerned at how fast the engine turns over. I hadn't remembered it being that fast but put it down to having fully charged the battery. When I come to think of it, the last time I had an engine fly over so fast on the starter was when I had a snapped cam on my Vauxhall Griffon 2.3. Maybe it has lost compression as Bodders suggests. I'll try sticking oil in the holes when the wife lets me. I hope it rains if I don't get it fixed this weekend.......Regards, Mark

[GRIFFONMARK]

My wife gave me permission to put oil in the holes so I put 10cc in each hole. I disconnected the cold start and removed the fuel pump fuse then wizzed the engine over to avoid hydro licking and took the inlet hose off to ensure crap from plenum would flush out. There was a lot of gunge around the throttle flap, a grotty petrol stinking mess (500 miles ago it was clean).
Brand new plugs were fitted along with a new coil and HT lead. The spark on no.2 has gone from orange to blue/white.

Trouble is the tasminger will still not even do a gnat fart. Yes, I did remember to replace the pump fuse. I'm not that daft? The oil definitely increased the compression as the engine did not wizz over anything like as fast.

I can't be bothered stripping down the plenum, although perhaps I should as I suspect it's swimming in gunge. Maybe I'll give it a good tow start and see if that clears its system. If anybody has any further ideas what to do please,please let me know as summer has just started in Preston.

Regards

Mark

[honestjohntoo]

GRIFFONMARK said:

I can't be bothered stripping down the plenum, although perhaps I should as I suspect it's swimming in gunge.

I'm sorta puzzled why you would think that way. Dont ignore the fact that the breather has deposited all that new gunge in only 500 miles. In comparison my plenum has done 20,000 miles since it was cleaned and is still spotless.



Yours should not do that and the gunge can block galleries and upset idle speed control. Worse, it can only come from the crankcase prolly because the piston ring blowby is quite bad which also explains your low compression issues. But it should still run if there are sparks and the mixture is correct.

May I point you back to my first post suggesting that you test the components that can induce overfuelling. If the plenum is sloshed with fuel as well, that does seem to point to the cold start injection system which squirts direcectly into the plenum, being faulty. As others suggest its sorta redundant in warm climates (even in Preston) so disconnect everything to do with cold start, seal the orifice into the plenum, then test the other suggested components. Oh! And clean the plenum!

The bottom line is you have overfuelling, you have gunge, you have excess petrol in the plenum, you have possible piston blowby. The sparks are OK so it should run, but the engine cannot fart if the mixture is not combustible.

[350zwelgje]

As mentioned before change the coolant temperature sensor first (or shortcut the connector to it for a test) before taking the inlet or engine apart....
Only my two pence.

Rob

[GRIFFONMARK]

Hi honestjohn. Nice clean holes you've got!

The reason I did not want to clean the plenum yet was that i like to change as little as possible on a non running engine as it is so often the case that by fixing things that aint broke you end up with a lot more broke things.

Good news. I got the car to start within a few feet of towing it but my God, the neighbours hate me now! If anyone else goes the same route make sure you tow the car a couple of miles away from home before you fire it up.

It now runs better than ever, and I thought it was pretty good before.

I suspect the coil and/or HT lead have not been up to the job and whilst they could start an engine in daily use they could not start a cold damp engine left for 3 weeks. I charged the battery before trying to start it meaning lots of turning over and as a result I think I completely flooded the engine and lost compression.

So now I know it runs OK and I can get down to changing the plug leads, cleaning the plenum and generally tidying it up.

Thanks to everyone for all their help.

Regards

Mark

[Bodmin]

Hi Mark,

Glad to hear you got it running again

I did try & warn you about the smoke ....just imagine what that lot would have done to a cat.....not the furry type....if it was fitted

Bodders