Engine idle problem / acceleration hesitation when cold, Throttle body changed now running out of ideas!! Options

[Fujifilm]

HI

I have a problem that I cant resolve, it started with a rogh idle so I cleaned the throttle body etc. That seemed to cure the problem but it came back, I checked vacuum hoses and they "look" ok.

I took throttle body of again and cleaned it same problem. So to eliminate the throttle body and the two sensors I purchased another second hand throttle body with sensors, installed and the same problem so now I have no idea what to look at. I also changed spark plugs and fuel filter.

The symptoms are....

When starting from cold the car is not very responsive, pushing on accelerator nothing happens then suddenly it will go. It does this until it warms up and then drives ok. BUT when driving with low revs it feels jerky. I can drive for ten miles with no issues, stopping at traffic lights etc. But occasionally the revs will drop so low it nearly stalls. When I get to destination and come to a complete stop it sometimes stalls. Leaving it for ten minutes then driving results in no problems.

The main problem appears to be from cold for about 5 minutes.

Can anyone offer any ideas, the car is a 1995 convertible st202 with 70000 on the clock, its got the one vacuum hose on thhrottle body and pre the extra resonator box.

Just add, I dont know when this started, when I purchased the car owner said it run perfectly but he left an egg cup full of fuel in it and it ran out on my way to petrol station, and it was empty as you possibly get! Could this have affected injectors, I would have thought if it was injectors it would do it all the time?

This post has been edited by Fujifilm: Jul 2, 2014 - 7:23 PM

[Special_Edy]

O2 sensor maybe? When you check the plugs is it rich or lean?