Omega Owners Forum

Omega Help Area => Omega General Help => Topic started by: harry3553 on 17 January 2008, 21:33:50

Title: Running Lumpy?
Post by: harry3553 on 17 January 2008, 21:33:50
Hi, recently purchased 2.0 8v automatic 1997 but since going out to supermarket tonight its running lumpy on tick over at about 500 rpm and when i reversed, it cut out twice, it also drives lumpy sort of wanting to go but holds back, not really bad but you can hear it irregular, any ideas?
Title: Re: Running Lumpy?
Post by: Auto Addict on 18 January 2008, 07:03:52
First thing to do is clean out the breathers and throttle body, see 'Maintenance Guides' section.

Also, remove the Ecotech strip, and check for Oil/Water in the plug wells.
Title: Re: Running Lumpy?
Post by: harry3553 on 18 January 2008, 17:55:59
Thanks for reply I will clean those items tomorrow on day off, after running it today though ive noticed that this problem only starts when the engine is warm so could this be something different? also this engine is the 8v not the 16v ecotech
Title: Re: Running Lumpy?
Post by: Kevin Wood on 18 January 2008, 19:24:05
If it's fine when cold it could be down to the coolant temperature sensor. This could be telling the ECU that the engine is cold when it's hot and consequently it's over fuelling.

Idle Control Valve is another possibility I'd say. Does it run alright under load and just messes about at idle or is it lumpy at all speeds?

Have you checked for fault codes in the ECU?

Edited to say: Try measuring the resistance of the coolant temperature sensor with a multimeter when the engine is both stone cold and hot. I'm guessing here as I'm not familiar with that sensor but it will probably read down in the hundreds of ohms when fully warmed up and significantly higer resistance when hot. Also check the connector for signs of corrosion, etc.

Kevin
Title: Re: Running Lumpy?
Post by: harry3553 on 18 January 2008, 19:46:11
Its fine when cold, and when at temp its really lumpy on tick over but when i accelerate it seems fine, plenty of power, just seems as though its guna cut out at anytime at junctions. I ve had my mates code reader on it just now and its coming back clear so ill probably have to take it to a garage tomorrow as i dont have a tester for the coolant sensor and without a manual yet i dont even know where it is, thanks for the info will let you know how it goes.
Title: Re: Running Lumpy?
Post by: Marks DTM Calib on 18 January 2008, 21:48:10
If its got no fault codes stored then concentrate on the ignition system first...check the leads, the plugs and the DIS pack.
Title: Re: Running Lumpy?
Post by: harry3553 on 19 January 2008, 17:55:37
Had another go at car today before it goes to garage on tuesday, ive replaced plugs, leads and cleaned breather pipes, replaced air filters, but still same, refering back to what kevin said,about the idle control valve, ive heard these can be cleaned out? Is this possible and has anyone any pics or info on it? many thanks
Title: Re: Running Lumpy?
Post by: cem_devecioglu on 19 January 2008, 22:54:48
Yep.They can be cleaned with carb cleaner..

http://www.omegaowners.com/forum/YaBB.pl?num=1194007453
Title: Re: Running Lumpy?
Post by: harry3553 on 19 January 2008, 23:12:20
Thanks for that info really useful, what i have tried tonight before i dismantle is take the small pipe off as deacribed and it has good suction so maybe the jet isnt blocked but i will give it a clean anyway, thanks
Title: Re: Running Lumpy?
Post by: cem_devecioglu on 19 January 2008, 23:15:53
More thanks to Grumpy ..He has done really good job..
Title: Re: Running Lumpy? problem found advice wanted
Post by: harry3553 on 20 January 2008, 13:12:00
Hi , Im certain ive found problem, last night id left it running and when i came out there was loads of steam out of exhaust, just put it down to damp wet night, on way to tesco today temp went really high, pulled over before it went into red and left to cool and there was hardly any water in system, took oil cap off and it was white, so head gasket has gone. Now when i bought this car 2 weeks ago he produced a receipt saying it had had a new water pump 1000 miles earlier, when i got it home i could see car dismantlers yellow paint on the head so presumably hed replaced the head so he must have boiled it when the water pump had gone, so what do i do now? do i have this head skimmed? i really dont want to get stung by a garage, can any one predict how much this will cost? any help/advice very welcome, Harry.