Cold starting an R300

[bluespeed]

I have a lovely R300 K series 2002/3 with the following issue:

She doesn't want to get going early in the morning, much like her owner.

Cold starting is a pain with 6-8 attempts before she finally struggles into life!

Warm she goes mostly straight away. Runs well.

She is a Standard car with standard R300 ECU and standard everything else.

 

I feel it is related to a sensor feeding back into the ECU

I am going to replace the small temperature sensor fitted to the water manifold (just above the exhaust) if I can find a new one (Caterham have no stock, part no. 71167) This gives 2K Ohm resistance when cold and about 300 Ohm when in boiling water, so seems linear in operation but worth a try.

Any creative ideas would be a great help, as always.... before I head/phone for a K series expert as don't like to be beaten!

Simon N

[skydragon]

Is the IACV working?

[jamiegb]

I would suggest checking battery condition first, especially if cold turnover is slow

[prangerman]

I have the same issue although it has improved over the years, particularly after having the RBs balanced. I'm now down to three presses of the starter button to get started from cold.

 

My procedure is to make sure the battery has been on trickle charge so that it has full ooomph.

 

depress clutch fully to reduce drag

 

open throttle a little

 

and hope for the best

 

I have previously used Sure Start or Start ya Bastard sprays in the RBs but it's not good that good for the engine, so 'tis said.

 

Peter

[bluespeed]

Is the IACV working? Ok I give up what is the IACV and how do I prove it is working please?

 

Battery is new and fully charged so she turns over very nicely, just without the necessary engine noises normally associated with pushing the red button!

 

Bit disappointed to hear others have similar issues but mine did used to start brilliantly (honest) so I supect a failure somewhere, not excluding me of course!

Thanks for the comments keep them coming please....

 

 

[Mark w]

The problem is your not using it enough and it's getting cold

 

 

 

 

[Bio]

Hi Simon

You have not got an idle control valve as your car has roller

Throttles.

At idle your throttle pot is set a little low at 0.39 (should be 0.44-0.45). This could alter the information fed back to the ECU and reduce the fuelling at start up .

 

John

 

 

[TobyCoulson]

Quoting bluespeed: 

Is the IACV working? Ok I give up what is the IACV and how do I prove it is working please?

 

Battery is new and fully charged so she turns over very nicely, just without the necessary engine noises normally associated with pushing the red button!

 

Bit disappointed to hear others have similar issues but mine did used to start brilliantly (honest) so I supect a failure somewhere, not excluding me of course!

Thanks for the comments keep them coming please....

 

Air idle control valve but I don't know how to test it either.

[bluespeed]

John,

Thanks for your comments.

 

I may attempt the slotting idea you proposed when we met to increase the feedback voltage from the rail pot to the ECU. My concern I guess is once upon a time it all worked perfectly and it must be that something has changed. I don't like fiddling too much as it sometimes makes things worse!!

 

One of my colleagues at work suggested that because the car doesn't get much use over the winter the voltage level on the battery could be below the min needed to be seen by the ECU when the battery is cold. Batteries apparently need regular use to work well even if fairly new, as the cells fur up.

 

So I am off home to put on the trickle charger and see what difference this makes (previously suggested by Peter).

 

We will see what happens tomorrow morning!

Don't think there is anything wrong with the water temp sensor seems to work fine and is linear.

Simon N

[spannermcmlx]

My understanding is this is a common problem with R300's as the cold start is disabled in the ECU. Even on days like we're having now it still takes a couple of goes to get it to fire up and a couple more in the winter or if it's been stood for a while.

Go to the Minister web site for how to do a basic set up of the RB's, worked for me, also when trying, depress the clutch but don't touch the throttle until it just catches and then only a tickle.

[charlie_pank]

Don't replace the sensor if you have tested it and it's working ok.

 

I don't understand your two posts. In one you say the battery is brand new and turning the engine over fine, in another you say that it may have lost voltage over the winter and you're going to try it on a trickle charger.

 

Is it new and fully charged, or has it sat doing nothing all winter?

 

If you run it off jump leads from another car, does it start first time? If yes, then your battery is weak - do you know how to check that the alternator is charging it properly?

 

If it doesn't behave any differently on the jump-leads, it's either an inlet air-leak causing a weak mixture, a dodgy sensor or connection meaning fueling is out, or fuel pressure is down. - Try sraying easistart in the TBs, this will confirm it's lack of fuel that's doing it.

 

Next thing is to work through the sensors and find out what their expected resistance/behaviour is and test them accordingly. I'd start with the throttle position sensor...

[bluespeed]

Thanks again for all your posts on this problem, I am aware the subject lacks a certain fun factor but hey ho.

Caterhams have given us all a lot of fun so a bit of pain is acceptable now and again. Anyway I spend more time learning about mine than driving it, my wife has great enjoyment in telling me.

 

Sensor now back in manifold.

 

In answer to the last post, sorry to confuse anyone: The battery was new before winter and car has been sorn over winter. It spins the engine over fairly well and suspect that isn't the problem. But running short of ideas.

 

"it's either an inlet air-leak causing a weak mixture"

I have removed the TBs during taking the engine out over the winter. I replaced the the gasket between TBs and the engine. If I cannot solve the starting issue I may do a second time (bit of a pain of a job but might have to be done)

 

I will check operation of all the sensors I can find first of all but have no target readings to go by so this is a stab in the dark. I know the Throttle position sensor is reading a bit low as John (previous post) confirmed this at 3.9v should be a little higher.

 

Easy start! - not seen or used since my 2 stroke Karting days as a kid but will find some to see what happens. Great smell.

Ta *wavey*Simon N

 

 

Edited by - bluespeed on 28 Mar 2012 21:51:42

[Cookie Monster]

FWIW John did exactly what he has suggested in his responseto you to my R300 (k series on TB's) a month or so ago.

The car still doesn't start first time(it never did) but if I crank it for 3 - 4 secs & then leave it for approx 5 - 10 secs & then re-crank it will fire no problem. I don't touch the throttle as I often start it whilst not seated in it.

As Spannermcmix says I think there is something in the cold start being disabled.

Balance your TB's too - I have instructions if you need them.

Mines still not a "start first time" but starts & runs much better thanks to John & the above

 

Edited by - Cookie Monster on 28 Mar 2012 22:10:07

[bluespeed]

Cookie Monster John has balanced my TB's recently and she runs great when hot.

The starting from cold issue I suspect is related to my engine out over the winter.

I have just tried to start her tonight took about 15+ gos and eventually she stutterd into life on no throttle. Once warm (30 secs running) starts every time first time AH!. Little bu**er!

 

I think I will remove the TBs from the engine change the gasket again and take great care in tightening up the nuts and bolts holding on the TBs to the engine so no air leaks.

 

Otherwise I am at loss, and it could be an appointment with DVA if he can fit me in.

Good night.

 

 

[6speedmanual]

Simon

Hope you are well.

I wldnt remove the throttle bodies just yet until you have the diagnosis.

If they have an air leak affecting cold start, it will almost certainly be sucking in air under normal running.

Test for this by spraying brake or carb cleaner at gasket interface. An airleak will draw the combustible fluid in resulting in a change of engine running.

 

Also, if you are sure the problem was not there before you pulled the engine, I would double check everything elec connectors to sensors.

 

Not quite sure about NO cold start in posts above. My understanding is that there is cold start/ cold running enrichment but, due to the RBTBs and lack of IACV, there is no fast idle.

 

For reference, my R400 starts well in all temps. A couple of turns of the crank and it fires. From cold I tend to raise the revs to about 1500rpm for 10secs or so. This heats the combustion chambers and it smooths out. Fron hot, a little tickle of revs helps clear it up but it is hardly essential.

 

As John already knows your TPS resistance is out, I'd try o correct that straight away. It will affect cold start and all running. Can help with RBTB set up if you require.

 

I'm back on the blat from 1st April so maybe meet up before too long.

 

Cheers

Peter

[Bio]

Hi Simon

I think an air leak would cause poor running all of the time. First correct the throttle pot setting, this may also have some effect on the idle speed so you might have to play between the two.

TPS should be 0.44-0.45. @ 1000 rpm.

 

John

[bluespeed]

John/Peter,

"As John already knows your TPS resistance is out, I'd try to correct that straight away."

I will follow your recommendations and adjust the TPS to get in the voltage range you have specified then see what happens. When I remove the end plate to increase the slot lengths should I be warry of anything?

 

John may give you a call before starting this procedure.

 

Many thanks

Simon N

 

 

 

 

[Bio]

Give me a call Simon