Does Anyone Have A Clue

[KARAOKEMAN]

I have recently bought a previa 2.4 petrol.

It runs fine when warm but when the needle is at about 1/4 of the way up the engine light goes on and it runs like a bag of preverbial dung then stalls. after about 10 mins of me trying to start it, it then fires up and runs (although rough) until the temp indicator is at the normal mark.

I have had the diagnostics on it and it came up with an O2 sensor (master and heater) and the coolant temp sensor.

At a cost of 142 quid I replaced the O2 sensor but cannot seem to find the coolant temp sensor....

If anyone has any advice on this matter it would be appreciated.

[propnut]

Under the drivers seat is an engine inspection cover. To get to this you need to remove the seat and seat mounting bracket as well as the carpet hold down strip. You can then lift the carpet to expose the cover. It is held down with about 12 bolts.

Under this you will find the cylinder head. To the right hand side you will see three connectors the top of which will be green. This is your coolant sensor. I would suggest you check it with a test meter before deciding to change it. If you scan my previous posts you will find a link to an on line workshop manual. Follow the instructions contained within it.

[KARAOKEMAN]

thanks PROPNUT I will see if this does it

[Percythebus]

I have a 2004 2.4 Auto Petrol Previa which I've owned from new. It's now on about 80K miles, but from about 30K miles onwards I've had what sounds like similar problems when starting from cold - the engine runs fine for about 2 minutes, then normally stalls - if I've driven off in this time the stalling happens whenever I slow down (and as it's automatic ther's no option to keep the revs up) - normally 1/2 way across a roundabout or T-junction. The local Toyota garages cannot find anything wrong - the throttle control was replaced (under warranty) at about 40K and made a difference for about 2 weeks, then the problem returned. The Oxygen sensor was replaced a bit later but this made no difference at all. At the 70K service I had the Coolant temperature sensor replaced but again it has made no difference. I've now got used to letting the car warm up thoroughly before I drive off - but if you find a likely solution I'd love to get it fixed as anyone else driving the vehicle is likely to end up in the middle of a roundabout with no engine - which means no steering and virtually no brakes! :(

[propnut]

I have a 2004 2.4 Auto Petrol Previa which I've owned from new. It's now on about 80K miles, but from about 30K miles onwards I've had what sounds like similar problems when starting from cold - the engine runs fine for about 2 minutes, then normally stalls - if I've driven off in this time the stalling happens whenever I slow down (and as it's automatic ther's no option to keep the revs up) - normally 1/2 way across a roundabout or T-junction. The local Toyota garages cannot find anything wrong - the throttle control was replaced (under warranty) at about 40K and made a difference for about 2 weeks, then the problem returned. The Oxygen sensor was replaced a bit later but this made no difference at all. At the 70K service I had the Coolant temperature sensor replaced but again it has made no difference. I've now got used to letting the car warm up thoroughly before I drive off - but if you find a likely solution I'd love to get it fixed as anyone else driving the vehicle is likely to end up in the middle of a roundabout with no engine - which means no steering and virtually no brakes! :(

Could be the MAF (Mass Air Flow) meter. It uses air flowing over a hot wire to ascertain how much air is entering the system. This then informs the ECU to deliver the correct amount of fuel to the system. Alternatively you could have a very small vacuum leak somewhere, most likely where a rubber seal meets an aluminium part. When cold and the metal has contracted excess air is allowed into the system which again throws out the fuel metering. When hot the aluminium expands to close the gap. The idle speed contral valve ISCV and EGR valve are also likely candidates. A problem like this needs careful diagnosis, not the modern lets change this then that and hope it fixes it approach.