Warming up hesitation - choke?

Hey all
I posted about this months ago with no luck, and have just lived with the problem up to now. But it's been getting worse recently, and I'm stumped.

March 1.3. Starts and runs fine. After about 3 miles, while she is neither warm (thermostat open) nor completely cold, she starts to hesitate badly if I accelerate. Cough, splutter. When not in gear she will stall unless I am REALLY careful and light on the throttle. (Coast up to the junction, very gently rev her up, slip clutch to go!) If she does stall, I either have to wait 1/2 hour for her to cool down, or turn her over on the starter for about 10 minutes solid with full throttle. Not good. Bye bye battery. BUT, if I'm on a hill she will bump every time, no problem. One she is fully warm she is perfect again. But then leave her for 30 mins and she won't start at all...

I still suspect the choke, not least because when she misbehaves like this tickover increases to about 1400 rpm. Can anyone tell me anything about the choke system? Can I disable it at all? It looks as though some coolant passes through the TB, is there temp sender in there somewhere? Is the choke mechanically operated by the coolant temp? Help!
I don't want to start replacing TB's or other parts, as she is a rusty budget banger. If I can't fix this very cheaply it'll mean her death soon... :-(

P.S. Vastly improved this over the winter by putting cardboard in front of the radiator. Engine and heater warmed up quicker, problem minimised, and noticably better fuel consumption on shorter trips. No good at this time of year though, as she runs hot and fan works overtime.
 
the coolant temp sensors are under the dizzy (the 2 wire one for the ecu, and the 1 wire one for the gauge)
 
I realise this may result in a rich mixture and high tickover - sounds like the symptoms already present!

"choke" - So.... do you mean there is no physical choke mechanism - it's all controlled by the ECU? What's the advantage of your parallel set up?
 
Not trying to change the diagnosis but those sound of a similar symptoms to mine. Car splutters, pull up to a junction and stalls. Having to keep revs up. My fault was the common throttle body soldering joints drying out. Resulting in re soldering. Could it be worth a shot. Would be a simple cheap fix?
 
Hey Jay101 - another Devonian!
Thanks for the suggestion, but I resoldered the TB when I bought the car as "faulty" and fixed it. I also did it again when this problem first started and it made no difference. When it misbehaves it will drop to tickover without stalling, but wants to die as soon as throttle is applied. It is definitely temperature related.
 
I realise this may result in a rich mixture and high tickover - sounds like the symptoms already present!

"choke" - So.... do you mean there is no physical choke mechanism - it's all controlled by the ECU? What's the advantage of your parallel set up?
yes the ecu increases the injector durations, to act as a choke, and a 2nd c/t/s makes it add less fuel
 
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