Hello Briskoda members

Today I would like to ask for clarification about the notion "COLD START" and some engine warming-up related issues. I will make some assumptions that I need you to approve or disprove.

1) To my knowledge, cold start means starting the engine when ITS temperature is not at operating temperature already (usually 90 deg. C / 194 deg. F). That has nothing to do with OUTSIDE temperature.

2) Based on that statement, it is perfectly OK the choke system is activated even if outside there are 30 deg. C (and engine temperature also). Of course, in summer the semi-automatic choke (my Feli has carburettor) will function a lot less time than in winter.

3) The choke system on Felicia with carburettor does 2 things, a) enriches mixture, partially closes the air flap then opens it gradually as engine is warming up, and b ) opens the throttle (fast idle of up to 2300 rpm) then gradually closes it (reduces rpm to idle - 800 rpm) to speed warming-up.

4) On Felicia with injection there is an intake manifold electric heater (hedgehog) that reduces the need of such high fast idle, up to only 1300 rpm.

5) Higher fuel consumption in the city and in winter is related to more often or longer engine warming-up cycles

Edited 20 August, 201213 yr by adurer

1) yes, "cold" from 'cold start' refers to cold engine, not cold outside, although they are related.

for instance, if there are 30 C outside and the engine cooled down to 40 C after a ride and some rest, you will have a cold start in some degree since the coolant didn't rise to 90 C.

2) yes, if the cold start system is functioning well (see my carburetor guide at http://www.briskoda....hl__+carburetor

3) yes

4) not sure

5) yes, among other factors. you don't wanna see instantaneous consumption during warmup it's enough you smell unburned hydrocarbons...

Edited 20 August, 201213 yr by masster

4) Also not sure - I've heard of the feature, but only in association with Bosch K-Jetronic and L-Jetronic (both mechanical injection systems, despite the name "Jetronic") systems.

Thank you so much for replies. I will consider my assumptions 1, 2,3, and 5 as true.

Remaining statement 4 needs clarification because when winter will come I prefer having a 'hedgehog' mounted than revving the engine to warmup.