I'm trying to save this mr2!!

[Pauln]

Sound like your making good progress. Don't forget that if the TPS isn't setup correctly that could also contribute towards rich running at idle by feeding wrong data to the ECU. So that may all go away when the clean and check the throttle body

Paul

[Jamez87]

It's only smelling rich when cold....once the temps warm the smell goes away and the idle stops dropping.

Don't worry I am listening though and WILL get it cleaned, just several people have mentioned the coolant sensor causing idle issues....is there anyway to test that sensor?

[Rob]

Have you changed the spark plugs and distributor cap / arm? Might be worth it......

[Rob]

Oh yeah and the temperature sensor is quite possibly another culprit - I had issues on this with an old rev3 engine in a Celica once.....

[Jamez87]

Plugs were black, so first thing we done was swap them for some denso plugs along with a new distributor and arm, was hoping that would be the end of it lol

[Pauln]

Here's the appropriate page from the manual for the water temp sensor:

Checking the water temp sensor

Paul

[Nic]

This is where I'm at now.....

Found the cause of the sticky throttle and why it was possibly idling high before. The throttle stop/butt had come loose, so throttle wasn't returning to where it should be, possible loose throttle cable too I guess. Anyway got that sorted.

At the moment, from cold, I turn the car on and the revs raise above 1k like they should and then drop down to roughly 900. At this point with the gauge still cold the idle jumps between 900 and 500 and the car smells really rich.

As soon as the gauge hits half way, the revs stabilize around 900, though it is still hunting and not steady but its not trying to cut out and it sounds better etc.

So its better then it has been. I'm now wandering if there is a link to the temp, instead of the throttle body? (Don't worry I'll still get this cleaned, hopefully at the weekend!)

Has the car been driven? If the ECU has been reset it *may* explain the idle hunting and rich mixture. It can take a few miles for the ECU to relearn some of the settings.

[Jamez87]

I was sort of on the understanding that leaving it running for 10 or so minutes was enough?

I'm picking up a coolant sensor tomorrow, its cheap enough so I'll get that in first anyway. Nothing to lose with that. Failing that we are going to test the o2 sensor and then pull out the throttle body.

She's going to get put on stands this weekend anyway, need to sort out the non existent handbrake, poor brakes/pedal travel and sort out the stupidly low and hard coilovers!

Fun times!

[Nic]

I was sort of on the understanding that leaving it running for 10 or so minutes was enough?

The engine will get up to temperature but isn't under any load or boost just running whilst stationary. The ECU once reset will run default settings, it needs a run out to relearn certain parameters. I'm not saying that is the problem but they do tend to run rich and idle can be a bit lumpy when the ECU is reset.

[Jamez87]

Right not the coolant sensor lol!

But start up is perfect now, revs hold perfectly its as soon as they drop down to 900 it has a problem.

So got to be a throttle off job!

[Jamez87]

O2 sensor readings:

We got roughly 0.100 at idle and 0.900 at about 2500 rpm.

Sound right?

[Pauln]

Not sure what you actually measured there. Voltage? resistance?

According to the manual, you are supposed to warm the engine up to normal operating temperature. Then run the engine at around 2,500 revs for two minutes to warm up the sensor, and holding the revs steady use an analog voltmeter to count the number of times the needle deflects over ten seconds. If it's 8 or more times, all should be well.

You can connect the meter probes to TE1 and E1 in the diagnostics port for this test.

Paul

[Jamez87]

I didn't actually teat it, my mate did, I believe it was in Voltage.

Car was warm and we used e1 and ox1

[Pauln]

From what I can gather, I think that's checking the direct feed to the ECU and I've no idea what the readings should be as I can't find any mention of it in the manual.

Hopefully some one else on here may know the answer.

Paul

[Jamez87]

Havnt got any further yet, turned my attentions to the brakes and coilovers for now. Just thought I'd see if anyone recognises the car?

[mrfil13]

Been along time since i tested the o2 sensor, looked at my old post.

http://www.imoc.co.uk/forums/viewtopic. ... highlight=

With E1 and TE1 connected and a voltmeter connected between VF1 and E1, run at 2500RPM when its nice and warm and it should fluctuate between 0-5v or more like 1-4v about every second.

This was tested using a cheap digital multi-meter from maplins.

With E1 to TE1 disconnected and running at 2500rpm its a stored value. Should be 1.25, 2.5v or 3.75v. 2.5v indicates all is good. 1.25v suggests its running rich and would lean out. This value is used when not in closed loop.

http://alflash.com.ua/vf1.htm


I have a OBD reader that plugs into the OBD port and connects to a phone/tablet via bluetooth using the toyobd1 app from this guy in Canada (http://jfbreton.blogspot.co.uk/)

Connects up and gives live readout of o2 sensor, TPS, idle control, coolant temp, injector % etc. They were about £25 delivered. Might help out. If your really stuck then i could arrange to post you mine to use assuming mine still works.

Don't recognise that 2 but it looks awesome.

[SonicSW20]

E1 to OX1 is a direct feed from the o2 sensor - you should see that steadily oscillating between ~0V and ~1V when up to temp. E1 to VF1 in diag mode is the signal from the O2 sensor that has been processed by the ECU - it outputs either 0 or 5V depending on what the O2 is doing. Reason for this is it should be easier to pick up on a multimeter as it isn't a sinusoidal wave like the output from the O2 is.

[Jamez87]

Thanks for the reply guys! I've kind of not done much for a couple of weeks due to other commitments!

Anyway yes with e1 and ox1 it was basically either roughly 0.100v on idle or 0.900v whilst at 2500rpm and wasn't oscillating between the two.

Car warms up like a champ from cold but once it starts getting to temp is when it plays up, so would make sense if it was an o2 sensor I guess?

Mrfil13 that is a very kind gesture and I may take you up on that offer!