Awful starting, black smoke, running too rich

[Ian T]

I have begun to diagnose the poor starting my car came to me with last week. I'd appreciate any pointers as this could be a common issue that is easily fixed. The symptoms are pretty simple and very consistent - switch on ignition, fuel pump primes, then crank for about 5-6 seconds before the car splutters into life, sounding flooded, cloud of black smoke and lots of petrol smell. It then idles with some hunting but drives pretty well. I previously thought it was better cold than hot, but this isn't the case, it Is always awful.

Plugs are fairly sooty, but not totally black (more brown on one side of the insulator).

I have checked the compression with the engine hot (just after radiator fans switch off) and got consistent readings of 185psi on all cylinders, which seems healthy.

The CO pot is set to 500 Ohms, I have tried turning it down to 270 Ohms and up to a few kilo Ohms but the car starts the same.

The Engine Management CTS appears to be below 200 Ohms when the engine is hot, I will have to check it again when cold, but the trend is negative with increasing temperature.

One interesting point perhaps is the behaviour of the dash while cranking - alternator light flickers and Volts gauge dips to just under 10 V. Probably normal, but the cranking is great - quite rapid.


Next thing I guess is to acquire an Elanscan interface, I have emailed Geoff to see if he has any available.

Any suggestions very welcome.

Thanks,

Ian.

[Fredjohn]

Ian

Sorry to ask an obvious question, but did you put the ECU into service mode before adjusting the pot? It won't work if you don't. See CO adjustment in WikiLEC.

Apologies if it's a case of grandmother and eggs

[Ian T]

Ian

Sorry to ask an obvious question, but did you put the ECU into service mode before adjusting the pot? It won't work if you don't. See CO adjustment in WikiLEC.

Apologies if it's a case of grandmother and eggs

Well, I got the expected resistances from the Wiki, but I didn't find Service Mode. I looked here: http://wikilec.9600.org/index.php/CO_pot

I still have my L plates on with this car, lots of learning to do.

I will go and have another look, I spent a couple of hours reading through the Wiki earlier - a great resource that I can see I will come back to time and again. I'd like to think I could add to it as well once I am more familiar.

Would the CO pot setting cause the behaviour I am finding here?

Cheers,

Ian.

[Fredjohn]

Try here instead:

http://wikilec.9600.org/index.php/CO_adjustment

Can't fully answer your question, but as it adjust the emissions, I would guess it changes the fuel/air mix to achieve it. There may also be other causes of course, such as injectors.

Like you I still need to keep reading: barely been here 2 years and still lots of areas are black magic to me!!

[maz_r]

Hi Ian,

Have you been through the manuals, kindly hosted by B-C-N here?

The Engine management manual has a whole load of info and diagnostic charts, including one for "hard start"....More reading, I'm afraid

Also has info on using the Tech.1 scanner, which you'll find interesting I should think

[HJ2]

Don't forget to clean your injectors in the process. A sticky injector might cause your symptoms as well. Just a thought!