New 420R won't idle cold

[ChrisC]

Does your fan run early?    Another minor problem my car has is the coolant temperature reading in the ECU is higher that the measured temperature,  My ECU sees 96+ degrees, but the IR temp gun can't get temperatures over 80.   So my fan runs before the thermostat opens or the rad is even warm.   I can either replace the stat with an 82 degree stat or try to get the coolant sensor recalibrated.    I can't remember seeing a "cold map", just compensation for the coolant and lamda.   If the coolant is under 60 lamda isn't used, but if the coolant is over reading this will be lower and the compensation for temp will be incorrect, resulting in poor cool running.

[mike150]

No, my fan only runs when the temperature gauge is over 100deg.

Surely the car needs fuel enrichment when cold?

[ChrisC]

Agreed but that comes from temperature compensation, i.e. 10% extra because the temperature is X degrees.    Problem is my cars ECU is seeing a higher temperature, so the fuel compensation is wrong.    In my case the fans run all the time, because the ECU is seeing a hotter coolant than the gauge (which uses a different sensor) is seeing or my IR temp gun is reading.    

I suspect your problem is not the same as mine, but I just wanted to see if your fans where running all the time to see if your ECU was not recognising how cold the engine is.  

[JNC]

John I'm surprised that you settled to the one size fits all map from CC after your upgrade to RBTB's , After your advice I upgraded to RBTB's and CC did the work and I was very pleased from the start ! A transformation a must for all Duratec 7's . But after a while doubt crept in and I visited the two Steve's , they ran the CC map first and they found quite a few discrepancies = fuel and no spark and spark and no fuel at different RPM's , they showed me the map and instead of the lines mirroring each other they were all over the place. Now I have peace of mind that the remap is for my engine and not a generic one size fits all .

I would advise anyone to get there car remapped to their engine rather than a generic near enough !.

[John Vine]

Yes, you're right, but at the moment the car runs very well, so maybe I was lucky in the generic stakes.

I've no doubt that in time I'll be visiting The Two Steve's again, but it's not a high priority right now. 

JV

[JNC]

Mine ran well but even better now 

[ScottR400D]

Mine was mapped by one of the two Steves when I had RBTBs fitted. It's transformed in all sorts of ways. Steady 950 idle hot or cold, much smoother at low revs, more responsive, not to mention the sound when the throttles are opened. 

[Nillbymouth]

Is the car new? I realise it's not the same engine but my Sigma 140 Supersport would not idle when cold after I built it and Caterham said it needed an ECU map update. It has been fine since they did the update. Why they didn't supply the ECU with the correct map in the first place is another story. Maybe you have a similar issue

[mike150]

The car is 2017 with 400 miles and they are sending my ECU back right now with some updates but they say it's not the final fix. Apparently they are still working on that.

I will find out if it's any good very soon then!