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Spent the last few hours on the Z with TubZ and the conzult. I have attached the results so was hoping if someone could answer a few questions?

 

The idle isn't stable, it goes up and down between about 700-800 constantly - is that a vacuum leak?

 

The left hand O2 sensor show as no reading on idle but blip the throttle quickly and it shows a reading then drops to nothing, if you increase the revs steadily it starts to read then drops to nothing? Any ideas?

 

The power balance test is different every time even when run straight after each other? Any ideas?

 

If any Conzult expert has any other comments based on the readings please let me know, btw the car is a standard JDM Auto TT with only an EGR bypass and needs a MOT so I can drive but want to make all is ok 1st.

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No disrespect Anthony, but I find it incredible that someone would buy a bit of equipment, and not have a clue about what to use it for. It's a bit like buying a best seller in Japanese and being unable to read it. To use a Conzult you should at least have a good knowledge of the Zed motor and what readings to throw up when using it, otherwise you are wasting your time. I would take it to someone who understands what the readout means and could probably adjust it whilst hooked up and running, or at least tell what has failed. PM Jimmer, he has a Conzult.

A> looks like the engine doesn't reach operating temperature, so first suspect is either the temperature sensor or thermostat

 

B>looks like both O2-sensors are dead, but it's hard to see from static pictures.

 

C> the ECU is struggling to keep the idle up, so I presume the base idle is set too low (can be set with the conzult as well)

  • Author
No disrespect Anthony, but I find it incredible that someone would buy a bit of equipment, and not have a clue about what to use it for. It's a bit like buying a best seller in Japanese and being unable to read it. To use a Conzult you should at least have a good knowledge of the Zed motor and what readings to throw up when using it, otherwise you are wasting your time. I would take it to someone who understands what the readout means and could probably adjust it whilst hooked up and running, or at least tell what has failed. PM Jimmer, he has a Conzult.

 

No offence taken. TBH it was put on the car to see how the motor that had just been dropped in was running, I haven't had the time to read the whole manual for conzult yet and knowing the are some conzult experts on here thought it would be a smarter option to get some ideas from them 1st as they have the experience. I would rather get some info from someone who knows rather than all of it from someone who is learning (i.e. me)

No disrespect Anthony, but I find it incredible that someone would buy a bit of equipment, and not have a clue about what to use it for. It's a bit like buying a best seller in Japanese and being unable to read it. To use a Conzult you should at least have a good knowledge of the Zed motor and what readings to throw up when using it, otherwise you are wasting your time. I would take it to someone who understands what the readout means and could probably adjust it whilst hooked up and running, or at least tell what has failed. PM Jimmer, he has a Conzult.

 

Apart from the fact that it's much easier to learn about consult and what it's telling you - and to learn more about your car - than to learn Japanese! With your thinking, knowledge would die as everyone would just look for someone else to do everything for them. Possibly the most ridiculous post I've ever read on a car forum - why don't we just get rid of all technical related info on here and tell people to speak to someone who knows what they're doing :headvswal :headvswal Unbelievable

No disrespect Anthony, but I find it incredible that someone would buy a bit of equipment, and not have a clue about what to use it for. It's a bit like buying a best seller in Japanese and being unable to read it. To use a Conzult you should at least have a good knowledge of the Zed motor and what readings to throw up when using it, otherwise you are wasting your time. I would take it to someone who understands what the readout means and could probably adjust it whilst hooked up and running, or at least tell what has failed. PM Jimmer, he has a Conzult.

 

Well thank fook not everyone on this forum has teh sam pissey attitude as you mate. I found things out about teh car by asking questions that I wouldnt know the first place to look by posting exactly the same way.

Well thank fook not everyone on this forum has teh sam pissey attitude as you mate. I found things out about teh car by asking questions that I wouldnt know the first place to look by posting exactly the same way.

 

Read the post again - it's not me with the pissy attitude! I agree with you!

Isn't it about time someone in the know made up a list of known parameters that numptys like me can use to check if our cars are running ok. ;) I have data scan and although i don't really know how to use it yet it has helped me solve a few little problems that would have cost more than the £75 i paid for it if i had taken the car to a garage. :D

As far as i was aware, operating temperature should be around 80*c (i think somone once mentioned 80 to 85) so yours is sat around 70 ish bit low... has it got a standard rad in there?

 

The idle at 750 is about right i thought?? Perhaps a little more 850 but its not a million miles out... as to why its having different drops in idle each time on different cylinders i wouldnt like to say.

 

I thought that the idea of the power balance test was designed to test cylinders that wernt firing and also as a rough guide to compression within the engine... Obviously the lower drop in revs the less resistance the "Dead" piston is giving so we assume that there is somthing wrong.

In your case though i think not, being seemingly completly random it must be somthing else.

I have never yet understood o2 sensors altho someone once said i tihnk that it was supposed to be about 12 changes in voltage every 10 seconds for a fully working one BUT somtimes mine sit and do nothing at tickover, other times they fluctuate nicely and other times they stick at values... Werid but i do know they only seem to do alot when your on the move!

Read the post again - it's not me with the pissy attitude! I agree with you!

 

 

sory worng person. appologies mate

  • Author
As far as i was aware, operating temperature should be around 80*c (i think somone once mentioned 80 to 85) so yours is sat around 70 ish bit low... has it got a standard rad in there?

 

Standard rad in the car. I've got some O2 sensor coming from Gibster so will fit them and try again. I assume the water temp sensors are the two in the top alloy rad hose? I have 2 spare so can change them to.

 

Any other feedback welcome. :hyper:

Check the connection for the yellow one. Temp would normally be about 84 deg C, 70 is low. Maybe it'd not warmed up yet ?

  • Author
Check the connection for the yellow one. Temp would normally be about 84 deg C, 70 is low. Maybe it'd not warmed up yet ?

 

Wil do, the engine had been running 30 mins!

In all honesty it wasn't fully warm but readings were similar to last time when it was! Would normally check it after a goood run and getting it up to operating temp. Unfortunatly, as we're looking to get it MOT'd we havn't got that Luxury!

 

PS. In answer to the 'Old Z' thread. It's my Conzult and was bought to check my car was running ok after being set up by a supposed 'expert'....(Mr Ryan Southall et al) In hindsight i'm glad i bought the ConZult despite not being able to fully diagnose the output as it certainly helped me understand that i wouldn't trust that 'expert' to change a wheel on the Z!! In fact i wouldn't trust him to screw in a light bulb properly after my experiences, which is why this forum is so useful and users shouldn't be berated for asking questions no matter how daft they can appear to those in the know!.

A> looks like the engine doesn't reach operating temperature, so first suspect is either the temperature sensor or thermostat

 

B>looks like both O2-sensors are dead, but it's hard to see from static pictures.

 

C> the ECU is struggling to keep the idle up, so I presume the base idle is set too low (can be set with the conzult as well)

Again Lymon is making sense :D You're so clever Eric!

 

If the temp sensor is not working, or the connection is sh1tty then it will probably run rich and the idle will be higher than normal. I know this from experience.

 

If the base idle has been ltampered with, this combined with a dodgy temp sensor will produce strange idle readings.

 

IIRC the O2 sensor readings will also affect the fueling and in turn the idle. Mayve someone could confirm this?

 

HTH...

Doesn't the Z have an idle control valve controling idle? ECU ignores 02 sensor readings on idle and when throttle is fully open?

As Eric says, temp reading is wrong. My bet is the base idle is not adjusted correctly. In fact, of all the cars I've looked at, EVERY single one has needed the base idle adjusting! Before anyone starts screaming, this isn't due to bad garages, its just that the orifice used for base idle changes diameter due to oily deposits from the breather system.

 

To get a correct temp reading take the car for a run, although if no MOT then that could be a problem lol. Its very difficult to get a Z up to operating temperature from cold with it just sitting at idle, especially at this time of year....

  • Author
As Eric says, temp reading is wrong. My bet is the base idle is not adjusted correctly. In fact, of all the cars I've looked at, EVERY single one has needed the base idle adjusting! Before anyone starts screaming, this isn't due to bad garages, its just that the orifice used for base idle changes diameter due to oily deposits from the breather system.

 

To get a correct temp reading take the car for a run, although if no MOT then that could be a problem lol. Its very difficult to get a Z up to operating temperature from cold with it just sitting at idle, especially at this time of year....

 

Temp sender unit and connection cleaned so I guess it's off to get another can of petrol, change the O2 sensors which are on route then sit in her and hold 2000rpm once the temp is up a bit to see if it helps get her temp up to normal. Then start checking things again!

Base idle is more critical than you would think, if this is wrong it can cause all sorts of strange problems....

  • Author
Base idle is more critical than you would think, if this is wrong it can cause all sorts of strange problems....

 

Is it best adjusted when temp is up to 80°C? Also it worth taking the screw out and cleaning it all out first? And lastly what causes the constant changes in the revs, as it make it harder to set when it's not constant.

 

thanks :D

Constant changes in revs could either be dirty throttle bodies or incorrect ignition timing. ALWAYS perform any adjustments at operating temperature!

 

No point just cleaning it by removing the screw - if you want to give it a thorough clean then remove the entire assembly, strip it and clean... Remember to always use a new gasket when replacing. You can however get similar results by removing the air feed to the valve and squirting plenty of carb cleaner in there...

.....Its very difficult to get a Z up to operating temperature from cold with it just sitting at idle, especially at this time of year....

Start her up from cold and Just bounce her off the rev limiter for couple of mins, should be nice and toasty then :D

Start her up from cold and Just bounce her off the rev limiter for couple of mins, should be nice and toasty then :D

 

:rofl: FFS don't say that people will actually do it :rofl:

:rofl: FFS don't say that people will actually do it :rofl:

 

Doesnt seem to bother saxos and 106's too much ! lol

 

All i hear when i drive through town!

 

I'll never forget reading a forsale ad, which had under the "plus points"

 

"Driven sensibly - never red lined when cold"

  • Author
Start her up from cold and Just bounce her off the rev limiter for couple of mins, should be nice and toasty then :D

 

Is that when she goes bang in a cloud of smoke and flames!!

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