Ongoing Caldina Issues

[BZG Wagon]

I've had an issue with my Caldina GTT since I bought it & I was wondering if someone out there might be able to shed some light on it.

1) I had a mechanic mate look at over the car before I bought it & there were no problems. I arranged a thorough mechanical test with a mobile company & it was carried out while I wasn't present. I was told the car was sweet, paid the money & took the car.
2) Immediately after picking it up I noticed it was knocking under throttle (it was insanely bad). Took it to Toyota - their mechanic told me it was the petrol.
3) I was told by a mate with a Celica GT4 (running 16psi on 96) that it didn't sound right so I took it to my mechanic mate who spotted a broken cable to a sensor in the air box (see pic below). Soldered the sensor & the problem almost went away.
4) When I'm in traffic & the car heats up it still knocks and gets worse under heavy throttle between 2000rpm to 4000rpm. It also does it occasionally during normal driving.
5) Had the cambelt changed & Toyota told me not to worry about sound so I've left it for a few months.

Now its starting to piss me off. I've since been told that this knocking / pinking / detonation is probably doing damage to the engine. I have also heard that GTT's can run 96 petrol without any issues (if I do this it will knock to death).
Lastly, I have been told that these sensors to the air box cannot be repaired / re-soldered because it mucks up their calibration. Could anyone out there please shed some light on any of this?



I've spent a lot of money on the car & its frustrating that I cant drive it the way it was intended to. I'm also fed up of going back and forth to mechanics with no solutions.

[Lloyd]

Just an air temp sensor. Shouldn't have any issues with soldering wires to it

[fivebob]

The air intake temp sensor is a 2.5k ohm @20°C variable resistor. In the range that the temp sensor oprates at (0-40°C) soldering would not effect the resistance enough to make a difference, unless it was a very poor job, however I wouldn't solder an unsupported connection like that, you're much better off using proper crip connectors.

As for the knocking, I would suggest trying to clean the carbon deposits of the pistons by carefully adding water to the intake and see if that makes any difference.

[sergei]

We had a mazda familia at work (well actual model is irrelevant), had similar problem on hot - excessive knocking, loss of power,while with disconnected water temp sensor made it run much better. Well after 3 month of trouble shooting it turned out that the crank shaft key was broken and cam belt sprocket moved affecting the timing, which was very hard to spot since ecu was compensating on idle, and ignition timing would show up ok.

[BZG Wagon]

The air intake temp sensor is a 2.5k ohm @20°C variable resistor. In the range that the temp sensor oprates at (0-40°C) soldering would not effect the resistance enough to make a difference, unless it was a very poor job, however I wouldn't solder an unsupported connection like that, you're much better off using proper crip connectors.

As for the knocking, I would suggest trying to clean the carbon deposits of the pistons by carefully adding water to the intake and see if that makes any difference.

Just to be clear, the wire to the sensor wasn't repaired, the sensor was taken completely apart and the wire was soldered directly onto the point of contact inside the sensor. Good point though - checking the soldier is probably the first thing to do.

As for carbon deposits, I was told of this but I thought it was unlikely as the car has only done 103kms & I have the full service history from Toyota Japan (it only had one owner since new). I was thinking of spraying some Clean'a'Carb through the throttle body to see if that improves things. Other than that is there any way to tell?

Lastly, neither myself of my mechanic mate noticed the knocking when we gave the car a good look over. We might have missed it, but I'm still leaning towards something either the previous owner did or the vechicle testester did when he was looking over the car.

[matt dunn]

Just to be clear, the wire to the sensor wasn't repaired, the sensor was taken completely apart and the wire was soldered directly onto the point of contact inside the sensor.

In that case I would bin it and get another, they are worth bugger all second hand anyway.
Will be the same as most 4AGE one's of the same style.


Matt

[BZG Wagon]

Just to be clear, the wire to the sensor wasn't repaired, the sensor was taken completely apart and the wire was soldered directly onto the point of contact inside the sensor.

In that case I would bin it and get another, they are worth bugger all second hand anyway.
Will be the same as most 4AGE one's of the same style.

Matt

I think thats a good idea. I'll have to look into that.

I have it booked in with my mate tomorrow at his work - we're going to hook it up to an error code scanner thing & if thats okay I'm hoping he has a few other ideas of things to check (I'll mention the carbon thing).
.

[ChaosAD]

Replace the sensor.
Reset ecu.
Make sure you use decent fuel.
Put the ecu in diag mode and check the ignition timing.

What do the spark plugs look like?

[fivebob]

I have it booked in with my mate tomorrow at his work - we're going to hook it up to an error code scanner thing & if thats okay I'm hoping he has a few other ideas of things to check (I'll mention the carbon thing).

No need for a scan tool, they're not OBD-II compliant. Simply locate the check connector, which is below the dash on the right side of the steering column, turn the ignition on and bridge TC & CG pins as shown in the diagram below. Then count the flashes on the Check Engine Light

[BZG Wagon]

Replace the sensor.
Reset ecu.
Make sure you use decent fuel.
Put the ecu in diag mode and check the ignition timing.

What do the spark plugs look like?

We pulled the plugs out when I first got the car (when mate discovered the broken wire). They all looked relatively new / clean. I will check them again tomorrow.

I've used nothing but 98 octane (except once out of town when I couldn't get any & the engine knocked to death - solved in part with a bit of octane booster).

I didn't think the timing could be set on these? Surely this is would have been checked when Toyota replaced the cambelt / water pump?

[matt dunn]

No need for a scan tool, they're not OBD-II compliant. /

maybe not,

but you will be able to live data of the current air temp reading,
because if the sensor in now reading 20 deg too hot or cold, it will still be in range and not log a fault code.

Matt

[BZG Wagon]

I have it booked in with my mate tomorrow at his work - we're going to hook it up to an error code scanner thing & if thats okay I'm hoping he has a few other ideas of things to check (I'll mention the carbon thing).

No need for a scan tool, they're not OBD-II compliant. Simply locate the check connector, which is below the dash on the right side of the steering column, turn the ignition on and bridge TC & CG pins as shown in the diagram below. Then count the flashes on the Check Engine Light

2 Flashes, 4 Flashes, 4 Flashes, 2 Flashes.

I'm just going to see if I can find out what they mean.

[BZG Wagon]

I'm so fu*ked off right now!!!!

24 - Intake air Temp Sensor Signal
42 - Vehicle Speed Sensor Signal

I told the mechanic at Albany Toyota about the knocking problem and I told him about the broken wire to the sensor and asked them to investigate it. I even left a letter sellotaped to the steering wheel of my car noting the problem and describing what was done to the sensor.

As for the Speed Sensor - I lost all my dials down the motorway and asked them to investigate that too (happened once and only once).

What pisses me off is that I was told, both times I took my car in, I was told there were no error codes coming from my car and just to ignore it. I have spent close to a grand getting the cam-belt changed, the water pump done and having this problem diagnosed.
When I picked up my car it was over the pits with someone working on it & I was told it was nothing they had finished everything they were going to do.

My extended family has spent tens of thousands of dollars at that yard over the past 10 years and I swear they are going to get an absolute earful first thing Monday morning.

I'm not usually an angry person buy sh*t I want to punch something right now.

[fivebob]

No need for a scan tool, they're not OBD-II compliant. /

maybe not,

but you will be able to live data of the current air temp reading,
because if the sensor in now reading 20 deg too hot or cold, it will still be in range and not log a fault code.

Not possible on the Caldina, there is not any data stream available on the check connector from the engine sensors. In fact I don't know if there is any data on the connector, despite it being an OBD-II type connector. Even the ABS still uses the code flashes.

[fivebob]

What pisses me off is that I was told, both times I took my car in, I was told there were no error codes coming from my car and just to ignore it.

Maybe, because it's not OBD-II compliant, it didn't work with their scan tool, though I find that hard to believe. Or perhaps they didn't know that this model is not OBD-II complaint and used the wron tool. Either way I'd be very wary about getting them to do any work in future if they can't do something that simple.

FWIW I originally thought it was an OBD-II system, purchased a scan tool and then found it wouldn't work, so I just tried jumpering pins till I got the engine check light to flash. It was only after doing that I found the diagram, and some instructions in Russian about how to check the codes.

[Mr Revhead]

a speed sensor fault only shows when the sensor is faulting though.
or under certain conditions.
have come across that in an ae111 carib, faulty sensor would sometimes cause a check light to show, but only when it decided to fault. didnt store codes. like wise my ae92 when i forgot to reconnect the speedo cable, above a certian speed the check light would flash every few minutes.
but never stored a code and never stayed on.
would it not be possible for the caldina to do the same?

[BZG Wagon]

a speed sensor fault only shows when the sensor is faulting though.
or under certain conditions.
have come across that in an ae111 carib, faulty sensor would sometimes cause a check light to show, but only when it decided to fault. didnt store codes. like wise my ae92 when i forgot to reconnect the speedo cable, above a certian speed the check light would flash every few minutes.
but never stored a code and never stayed on.
would it not be possible for the caldina to do the same?

I'll check the codes again.

When my dials died (all of them; rev counter, speedo, thermostat, odometer) the check engine light immediately came on & stayed on. Turning the car off & restarting it bought them all back to life and I haven't seen the check engine light since.

When my mate disconnected the speedo on his GT4 (ST215) the same thing happened - constant light, reconnect it and start the car & it was gone. However we never checked to see whether there were error codes at a later date.

[Mr Revhead]

it is quite possible that the caldina is a little different from the cars i have had experience with, which is why my last sentance was a question

[BZG Wagon]

Well I went down & spoke to the service manager at Albany Toyota.

His offer to put things right:
* Run it through a scanner & see what codes are coming out & investigate.
* Check cam-belt settings.
* Check timing.
* Investigate the repaired sensor.

Carry out the above checks for free and I will only have to pay for what repairs or parts are needed.

Still a bit of a pain that I have to leave my car with them for a few days but I guess its a start.
_______
In the mean time I was told by a mate that the ECU can put the car into a 'limp home mode' & possibly resetting it could improve the situation. He reckoned the is a small chance the air sensor is working & the ECU is overriding the signal.

So my next question would be how to reset the ECU? Is it as simple as leaving the battery cable off overnight?
_______

[fivebob]

In the mean time I was told by a mate that the ECU can put the car into a 'limp home mode' & possibly resetting it could improve the situation. He reckoned the is a small chance the air sensor is working & the ECU is overriding the signal.

So my next question would be how to reset the ECU? Is it as simple as leaving the battery cable off overnight?

It's a bit of an internet legend, at least as far as Toyota ECUs go. There's very little, if anything, stored in the ECU as far as altertions to the timing, and the codes you have are certainly not enough put put it in limp home mode.

Easiest way to "reset" the ECU is to remove the EFI fuse for 30 seconds