Stalling at idle

[olly]

Our Cerb is currently off the road, but I'm still trying to start it on a regluar basis to keep it healthy. Recently it's been struggling to idle properly though. It's trying to idle at about 400-500rpm, so I have to pic the revs up slightly to stop it stalling (very small amount of throttle).

Is this a sign of needing new throttle pots, if so, is it just a case of fitting some new ones, or do they need setting up in some way ?

Thanks in advance

[_DJ_]

olly said:

Our Cerb is currently off the road, but I'm still trying to start it on a regluar basis to keep it healthy. Recently it's been struggling to idle properly though. It's trying to idle at about 400-500rpm, so I have to pic the revs up slightly to stop it stalling (very small amount of throttle). Is this a sign of needing new throttle pots, if so, is it just a case of fitting some new ones, or do they need setting up in some way ? Thanks in advance

Could be the battery that's low on charge? Are you using a battery conditioner in the garage?

[olly]

Battery has had it, so am starting off a booster at the moment & leaving connected while it's running.

Will be replacing the battery in the next couple of weeks though.....

[andy4200]

Mine does stall in the cold until I've had it running for a couple of minutes, in summer it's fine.

Must be the weather.

[Habib]

Am I missing something or is it just a case of adjusting the idle screw rather than new throttle pots or something.

[kojak69]

I would think its a case of a few things..such as weather and maybe throttle pots. Regarding adjustment of the pots, i'm not sure. I leave that to the experts (happy new year Joolz). I cant see it being the battery once the engine is going. If the battery is knacked, it'll struggle starting in the first place.

[whatever]

sounds like the damp to me. Should get better once it's been warmed through.

[pdavison]

Mine had this when the previous owner had it. Search through the forum as it's covered and from memory is was fixed by a dealer adjusting the throttle pots.

To be honest, it still does idle far too low and occassionally stalls, but once it's warm it's fine.

[suffolkfox]

If the battery is knackered it will almost certainly be this, as at tick-over the system does not produce enough voltage to charge it (there is another recent post re charging www.pistonheads.com/gassing/topic.asp?t=73151&f=6&h=0 that covers this) so once you start it, unless the revs are held up you will be effectively holding a duff battery at status quo, hence it will stall. Get the battery changed then have someone with the software check the ECU. As you will have been running on low voltage, the maps will probably benefit from resetting, as the system will have been trying to compensate. This may re-establish a stable tick-over (if the battery change alone has not already done this)

[gixxer1000]

I had the same issue and the problem was traced to a faulty throttle switch. Replaced in minutes and now ticks over like a dream.

Hope this helps
Gixxer

[leszekg]

My 4.5 started doing this a month or two ago. Sometimes stalling for no reason after being up to 5 minutes into my journey. The throttle pots were replaced as was the temperature sensor. It's now behaving better but still stalls immediately on startup from cold. If I keep my foot on the throttle at about 1500 revs for 10-15 secs then it's ok after that. Is this normal? The car is kept garaged in a dry and semi-heated garage so it's not as if the car is getting damp or very cold. It didn't do this last year but then it may have been set up differently at the last service.

[gary judd]

mine done the same so i was told to unplug the ECU for an hour then replug it problem was sovled if not then you will have to take into a tvr dealer and have it set up on the computer. hope the first works good luck.

gary judd

[joospeed]

It's quite common for them to stall from cold start if the hot idle is set to lower than 900rpm, the problem is the low idle airlfow and laot of ignition advance that TVR use, opening the airlfow and retarding the ignition would cure it so you could wind the advance back on for cold start .. in the short term you cna reduce the throttle pot values to retard the timing but it's only slight and makes the fuelling start on a weak part of the map which can aggravate any weak running problems if you already have any.

You can modify the throttle linkage to allow a bit of throttle opening on cold start.

Disconnecting the ECU doesn't work on the cerbera, the memory is non volatile and can only be erased with the laptop, if it clears any fuelling value and fault codes you have a fault with your ECU.

When the cerbera was released dealers were told to advise customers to keep a few hundred extra revs on for the first 30 secs or so, that's TVRs approved technique for cold starts!! .. try telling that to a porsche owner though lol!!

leszekg said:

My 4.5 started doing this a month or two ago. Sometimes stalling for no reason after being up to 5 minutes into my journey. The throttle pots were replaced as was the temperature sensor. It's now behaving better but still stalls immediately on startup from cold. If I keep my foot on the throttle at about 1500 revs for 10-15 secs then it's ok after that. Is this normal? The car is kept garaged in a dry and semi-heated garage so it's not as if the car is getting damp or very cold. It didn't do this last year but then it may have been set up differently at the last service.