Yaris Conking Out

[ollies]

Had a few problems with the yaris recently, tis a 1.0 x reg (2000 I think), 78k milage.

Started misbehaving on a v cold morning, as they do. Car cranked over but no spark...

Next day started fine, engine light on so drove it to garage, they couldn't find the problem and reset the MIL. Car worked fine for a few days...

Next time, same problem, car wouldn't start so waited couple of days till it did go (MIL was on), and drove to garage no2, who also couldn't find a problem so reset codes again.

Couple of days later... car dont start :censor: , so keep trying and next time it goes (couple of days later) take it to toyota dealer £££... no prob detected. Don't know why there wasn't anything stored, perhaps I cleared codes by disconnecting the batt. Next time it mis behaved I shorted the connections on the 16pin doo da and got a 12 error reading, which I think means engine is set too !Removed!, although I could well be wrong.

So, couple of weeks later car decides it'll go again so I decide to drive it 100miles to my folk's for a do on the inspection pit, on way down it cut out in rush hour in fast lane of A1 (stupid I know, wont be on a motorway again till its fixed for good). Anyhoo, after being towed off the motorway the bloke bump started it as he off loaded. So as car was now running again I continued on B roads and 4hrs later got there, just. Car broke just as I'd got up the drive when the revs dropped.

So today I done oil change, oil filter change (thought oil control valve may be sticking but wasn't) and sanded all earth connections. Car seemed to run a bit better but then did its cutting out trick again.

Tested for spark and nothing,

Checked for voltage to injectors and nothing.

Checked voltage to coil pack 12.5v on red wire, 5v on other wire

Therefore concluded coil pack is not being switched by ecu to generate a spark. Before I could do more tests car started running.

I'm now guessing either ECU is knaked or a sensor is iffy (causing ecu to immobilize).

Anyone got ideas? Going to look at crank shaft position sensor tomorrow and ECU connections but getting a bit desperate now...

Will update on any progress.

[Rumbly]

Hi Ollies,

Not really got any answers to this one, these intermittent faults are always a right bu**er to trace. Sounds like either a faulty connection or a faulty "black box thingy", could be anything, even a faulty solder joint on a component. If you can find somebody with same car willing to help out .. not always possible I know .... maybe swap out the ecu/sensors one at a time?

Hope you get sorted out asap

[stantheman1]

I would have been more inclined to know what the fault codes were before being reset, that way you could go about trying to find a solution using the process of illimination method.

As a matter of inerest what pins did you short out at the diagnostic plug and why?

I do know of a problem where the car refuses to start but this doesn't usually put the MIL light on, it is normally caused when you first start the car up (usually on coldish mornings) and then stop it a few seconds later causing a large amount of unburnt fuel to wet the plugs thereby 'flooding' the engine. The quickest way to start the car again is to floor the gas pedal as you crank the engine over for at least 30 seconds,OR you could leave it for 24 hours or so!

[Madasafish]

First point to look at : crankshaft position sensor. If it fails - and they can intermittently - symptoms as described..

Quite cheap and easy to replace...at base of timing chain cover beside the crankshaft..

[ollies]

Ok, got car back home from my folks but had another breakdown and another ride in a tow truck.

Car kept stalling so had to bump start a lot, bit tricky at junctions cos have to brake clutch and accelerate (to keep revs up) all at same time!!!

Anyways, inevitable happened and refused to bump. Had some interesting noises from the boot so thinking fuel pump although I dont see why this would stop the injectors or spark plugs. perhaps ecu immobilises them if fuel pressure too low? Either that or I have 2 problems with the car. Crank shaft position sensor is in a corroded bit of engine cos there is an opening beside radiator letting weather in so still think it's suspect but bit awkward to remove so not got it out yet.

For info - On the 16 pin plug I shorted pins 4 and 13 and that made the MIL flash a code at me, didn't help much cos not confident I know what the code means (12).

Will update shortly with progress. Don't think I'll try driving it anywhere till fixed.

[ollies]

Petrol pump fine, crankshaft position sensor tested and no circuit therefore knackered.

Tried to get sensor out and snapped off in engine block, v tricky to get at (inspection pit reccommended). Going to have to drill out i think. Not sure how snapping sensor can be avoided, pretty well stuck in, in my case. If doing again Id be more even with the screwdriver (used to prise sensor from engine).

Also new sensor has to be ordered through dealer, was going to get one from scrappie but after struggling with mine not sure if i'd be able to get one out in one piece. So £106 for a new one!

Any ideas for getting end out? Flat break so pliers no good.

[Madasafish]

Any ideas for getting end out? Flat break so pliers no good.

I would very carefully drill a very small hole in the centre of what is left - as a pilot hole. Then drill a larger one to accept a screw extractor.

http://homerepair.about.com/od/interiorhom...w_extractor.htm

Then insert screw extractor and screw it up tight. THEN - and only then, spray the sides of the broken sensor with plus gas (or WD40 but imo plus gas is better).

Go away for 24 hours to leave to soak in.

(I find vinegar works if neither is available).

Then unscrew screw extractor and hopefully the sensor will turn and come out

Maybe someone has a better way?

[cully]

I would have been more inclined to know what the fault codes were before being reset, that way you could go about trying to find a solution using the process of illimination method.

As a matter of inerest what pins did you short out at the diagnostic plug and why?

I do know of a problem where the car refuses to start but this doesn't usually put the MIL light on, it is normally caused when you first start the car up (usually on coldish mornings) and then stop it a few seconds later causing a large amount of unburnt fuel to wet the plugs thereby 'flooding' the engine. The quickest way to start the car again is to floor the gas pedal as you crank the engine over for at least 30 seconds,OR you could leave it for 24 hours or so!

Or, if you are in a hurry and flooring the accelerator pedal has not worked, (i) pull out the fuse for the petrol pump; (ii) turn over the engine on the starter for a bit, but it doesn't need anything like 30 sec. (iii) replace the fuse and restart the engine - after a bit of a pause.

Cully

[andycam06]

lad its too late and iam too tired to read all the posts, so if mine is now stupid ignore it, but i seen the heading and thought ild reply.

my corolla used to knok out rendomly, yould never when, turned out to be dirty fuel, i had to get the tank cleaned out but i had left it so long i needed a new fuel pump

[Claire1983]

Dont really know anything about cars but exactly the same thing happened on my last car. My brother (mechanic) changed the Battery and it never happened again.

Sorry if this sounds stupid.

[wastedagen]

Had the same systoms in two cars now. The first was a Corsa and turned out to be a Knackered Crankshaft sensor, which by the looks of it you're in the middle of changing. Bye the way good luck getting the bugger out............

The second was recently on my Dads 08 Yaris Sr. That turned out to be a bad cable to the Battery. Not sure which one though as Toyota didn't elaborate.

Regards