please help. problems with car start and idle

[jack1781]

hello,this isan overview of my problem. i have a gh sigma 4G52 2.0 engine. the issue i am having is that when i start the car when thee engine is cold it is really difficult to start, can take hours, then once it has started it doesnt idle until it is warmed up. when it is warm the car will then start, idle and drive perfectly.
i guess the idle when cold is due to the fast idle screw unless someone has any other ideas but i cant figure out the difficult to start.

here is a overview of the work i have done, originaly when buying the car i stripped and did a lot of work to the vehicle. all engine gaskets,complete cooling system etc.

i dont know of there is a cold start system on the car that may not be operating i dont have any ideas why it should be doing this. i have done the timing and checked the spark, all the plugs and cables are new, distributer seems in good shape, changed the cap, wiring seems to be all in as it should

any ideas will be greatly appreciated,

regards jack

[LukeAussie]

Hi Jack,
Given that you've investigated all the electrical stuff and ruled that out (buying new components), I'd think about checking your carbie next. Not only the fast idle, but also things like your fuel mix, blockages, etc, as these things will affect the cars' abilitiy to start as well as to idle. Do you know if the carbie has been re-conned at any time?
Good luck!

[geezer101]

Good advice from LukeAussie on the carby. Also you should do more than check the timing and the spark plugs when it comes to the ignition - if it's running a points distributor check the dwell angle as well using a dwell meter. It might be just enough out of spec to make it difficult to start but my bet will be that there are a combination of issues affecting how the engine's running.

[Sigmaproject]

Sounds like an issue with the Choke. It will be either electrically operated through the ignition switch or manually operated through a cable. If it is not working..then cold starts will be a problem.

[jack1781]

ruled out the choke as it should have atleast been firing even without the choke, and the distributer is electronic.the carbie mixtures would have an affect once it was running or atleast on the edge of starting,.

when through a few things turns out the fuel pump on there from the previous owner didn't have enough KPA so was starving the engine, r-did the rotor and cap on the distributer and changed plugs, rewired some of the wiring from the previous owner on the ignition again and changed some of the vacuum lining, also realized it was only firing on two cylinders and two of the plugs had gone and now its working,

think it was done to a combination of each of these things,poor fuel, vacuum leak, poor spark and mainly no spark n two cylinders.

re tuned the carvy now its running like it was new, so happy!!

[geezer101]

Good stuff jack1781, always nice to see someone get a win.