Previa Strange Electric Problem

[Nad999]

I have a very strange problem with my Previa CDX. It cranks and refuses to start but once you remove the negative terminal from the Battery and reconnect it, it kick starts and runs like normal. After a few starts it starts to crank again and gradually the cranking goes longer every time. It will start from 2 seconds crank and then starts up, the next time its 4 seconds of cranking and then it starts up, it goes on until its only cranking without a start. BUT if you reconnect the Battery, it kick starts again. I have changed the Battery, fuel filter, crank sensor, cam sensor, air filter, oil filter, spark plugs. I have shown this to about 5 mechanics and they have given up on it. I think it is an electric issue and it will reset whatever the problem is as soon as the battery is disconnected and reconnected. I am not sure what is causing the issue. Can someone please advise before I take it to the dealer.THanks so much !!

[bothwell_buyer]

Have you checked the earth connection on the chassis ?

[Nad999]

How do I do that? There a cable from the Battery that is screwed to the body of the car near the bonnet. Not sure about the chassis. Please tell me how do I check that ?

[bothwell_buyer]

How do I do that? There a cable from the battery that is screwed to the body of the car near the bonnet. Not sure about the chassis. Please tell me how do I check that ?

Its really to make sure that the Battery connections are tight; that the connections to the body and engine are good, and not corroded. You can try a multimeter, or even try a set of jump leads - using a jump lead from the earth of the Battery to the engine block.

I had a funny problem on one of my RAVs, and it turned out to be the earth cable to the engine had corroded and wasn't heavy enough to carry the current needed.

[Nad999]

I will try to do that, I can see the bolt touching the body that is coming from the cable that is connected to the Battery looks quite rusted.

But I was thinking that might not be the problem as what changes happen when I reset the Battery (negative) terminal. The rust is still on the bolt but it then kick starts.

I think its more to do with a relay problem. I am not sure which relay though, it can be an ignition relay or something similar, I dont even know how to figure out where the ignition relay sits. Dont you think its more like an electric thing not working well, when the Battery is reset, this "electric" thing resets itself and works for a couple of times and jams again?

[bothwell_buyer]

I will try to do that, I can see the bolt touching the body that is coming from the cable that is connected to the battery looks quite rusted.

But I was thinking that might not be the problem as what changes happen when I reset the battery (negative) terminal. The rust is still on the bolt but it then kick starts.

I think its more to do with a relay problem. I am not sure which relay though, it can be an ignition relay or something similar, I dont even know how to figure out where the ignition relay sits. Dont you think its more like an electric thing not working well, when the battery is reset, this "electric" thing resets itself and works for a couple of times and jams again?

I don't know the electric system on Previa very well, but I do know that a slightly lower voltage can affect the way that things work.... and that if their is additional resistance like a bad earth connection, then things can work oddly. Its a more common issue as the car gets older of course.

[Nad999]

I got it fixed at last !!

I took the car to a toyota dealer and they said the error codes were P0171 abd P0174 that relate to either sensors or something to do with the air flow system.

They narrowed it down to a Air Flow Meter and replaced it for £126.00+VAT+ Labour(£120).

The car is now running well with no cranking at all.

I have got the engine light turn up after 10 miles of driving and took it back to the dealer, they checked the code and now the code is P0420 and P0430 that relates to the Catalyct Converter. The technician cleared the code for me saying that it might be due to them opening the part and that might have triggered the code after dust particles got into the system. He said if the light come back again, they will look into changing the CAT converter. I read some forums that it might be due to air leaks from the exhaust pipe (Y pipe) or manifold. I will wait for the light to come up again and see.

But thank GOD they resolved my BIG issue of cranking.I should have gone to them in the first place instead of trying out the cowboy mechanics.

[jirehn]

Did you try to replace it?

[treborzg]

Very often problem in Previa-s. Clean ground connection from the Battery to the car - it must help.

You spent unnecessarily your money. p0171 and p0174 are temporary fault codes. It was enough to clean them.