Hello guys,

I would appreciate your advices for this topic.
Symptom:
Recently my 3.0 V6 starts with only 4 or 5 running cylinders in the mornings, although it isn't really cold, over zero degrees centigrade. It is confusing, that if I stop the engine immediately in 2 seconds and start again, it runs perfectly!
The other annoying symptom is the check engine light. If I drove on a graduate road with modest acceleration, the light is on for a while.

Conditions:
I have owned this car for the last 6000km or 4000miles.
After buying, I replaced the spark plugs with others as well, they are NGK BKR6EK plugs from ebay. It is confusing, that the german NGK agvisor tells BKR5 for the X30XE, the english webpage suggests BKR6. BTW my mechanic told not to build in NGK at all.
The car runs on LPG!

Questions:
-Am I right to start the investigation around the ignition system?
-If I go for replacing the ignition leads, what should I purchase? (I have found on ebay sets from GBP 17 up to 150+...)
-Shall I replace the ignition coil with the leads too?
...
What are your suggestion? :)

Regards,
Peter

imo before replacing anything, clean the fuel injector socket and plug on and off several times..its behind the plenum..and check for the cuts on the cable as it may short etc..

ps : please update your profile so nearby members can have a look..

It would be worth doing a paperclip test to see what the engine light was for.

It could be that you have a failing MAF sensor that is causing a lot of fuel trim. During cold start, the system is open-loop so it's running lean, perhaps. Once it goes closed-loop the system masks the MAF problem.

Just a theory. It needs investigation. Generally, if the problem is ignition, you won't find any fault codes in the engine ECU.

If you've changed the plugs recently I assume you would have noticed any oil or water flooding the plug wells? This can be an issue.

Coil packs can fail. It might be worth inspecting the coil pack and checking for bulging where the insides have got damp and rusted. I'd expect problems when hot as well, though, particularly under heavy load at mid-RPM.

Another possibility is the coolant temperature sensor reporting a warm engine when it's cold. Start with a paperclip test, though.


Kevin

Thanks, I'm going to borrow an Op-com device to read all the faultcodes. A friend here offered his spare coilpack for a swap test. I will come back with the results.
If anyone have more ideas... welcome!

Thanks again.

please check
http://www.omegaowners.com/forum/YaBB.pl?num=1189022687

Interesting!!

I have got 13 : O2 sensor open circuit.
I have replaced both senors 5 days ago, because of this faultcode. Maybe it wasn't enough to remove the battery cable for a few mins only and it didn't clear the faultcode?

Peter13 wrote on 13. Feb 2011 at 14:20:

Interesting!! I have got 13 : O2 sensor open circuit. I have replaced both senors 5 days ago, because of this faultcode. Maybe it wasn't enough to remove the battery cable for a few mins only and it didn't clear the faultcode?

Only worry about current fault codes, ignore 'saved' or 'historic' codes, if the e.m.l. is on whilst the engine is running then you have a problem.

I have connected yesterday a friend's opcom to the OBD2 to clear the fault 13.
I have seen a new one:
19 - wrong RPM signal.

My friends still suspect the ignition system. Other symptom is when I brake the car suddenly, when the speed reached zero or almost zero the RPM falls below 500 then it run over 800... sometimes makes this 2 or 3 times before setting to ~600 again.

Peter13 wrote on 20. Feb 2011 at 18:02:

I have connected yesterday a friend's opcom to the OBD2 to clear the fault 13. I have seen a new one: 19 - wrong RPM signal. My friends still suspect the ignition system. Other symptom is when I brake the car suddenly, when the speed reached zero or almost zero the RPM falls below 500 then it run over 800... sometimes makes this 2 or 3 times before setting to ~600 again.

Code 19 is the crank shaft sensor.  :y

Gentlemen,

I am still facing the cold start even it is now between 5-10 degrees here in the mornings.
Some days ago I was driving on a gradual road upwards with constant acceleration on the highway, and I got the MIL on again. It was on until I clicked off the cruise control and kept off then all the way to home.
I did the paperclip test again, but have found only 89-lambda sensor heating, low voltage (I think this is caused by the different resistance of the aftermarket sensor)

Does this mean any serious?

This weekend I am going to replace the coil pack, spark leads and spark plugs, all to brand new. Is there anything else to try? (I have friends who I can borrow parts for testing)

Thanks Guys!

Peter

If you have code 19 stored I would change the crank sensor.

This can cause other issues as it affects the engine's RPM calculation which is the basis for most other engine parameters.

Unfortunately, due to cable routing, it's not easy to swap one from another car for testing.

I wouldn't change parts at random. Save your money and focus on the things that the fault codes are indicating. If you end up with no fault codes but are still having problems, then it's time to consider the ignition system.

Lambda sensor won't affect starting to any degree. They come into play when the engine has been running for a few minutes. Code 89 on this ECU means "O2 Sensor 2 Open Circuit". It doesn't monitor the O2 sensor heaters.

Kevin

You are right, I was checking a wrong list of fault codes for 89.

I have never seen again the code 19 since I have cleared it 2-3000km ago. However, when I had a look with an opcom device, it showed the idle rpm was around ~720 and the throttle position was 8%!
As far as I know they should have been 600 and 0%.

Open circuit for the sensor is annoying, I have just replaced both few weeks ago.

Hmm. If the 19 isn't recent then maybe it's something else. Can you get live data from the opcom? In particular the block learn parameters and the whole list when the engine is idling and warmed up would be interesting.

Kevin

Thanks, I will try to collect live data before and after the weekend's work.

Hello,

I could manage to collect some logs while driving to the office this morning.
They are available for download at http://landboyz.4step.hu/

I can not see any serious, but honestly this is the first log ever seen and made.

The IAT is with 15-20 degrees above the real outside temperature, is that normal?
Do anyone see anything suspicious? (the car was running on LPG)

Excellent. Live data doesn't look too bad except that the Idle BLM integrator for bank 2 looks a little low. Both shouldn't be too far from the central value of 127. That said, the lambda sensors are clearly working fine and in closed loop.

MAF output looks a little high at idle in some places, but it's OK in others, so probably not an issue. :-/

Kevin

Thanks for looking at!

quick news:
Yesterday I removed the inlet to check the ignition system's status. I have found some sicknesses:
-there were some oil in the inlet pipes (but the engine does not consume much oil, something around 1-1,5liters/10k km)

-the pipe smaller pipe going to the fuel pressure valve was leaking

-the spark leads were cracked at the spark plug side

-I have measured the compression, each cylinder produced between 11 and 13 bar.

-I smell coolant at every stop, coming from under the hood, but it was not the coolant bridge that fails. I found the pipe coming from the thermostat towards the cooler. It wasn't leaking for sure, but had a bad wear at the engine side, caused by the fixing.

That's all news from my omega this weekend. Next week the leaking pipes, sparkplugs and leads will be replaced. We will see...

Any comments are welcome.

Thank you for all helping me out!

The cold start seems solved now, or at least I hope it is not starting fine only because of the better weather rather than the new ignition parts.