My car is a 1990 NA jap import. It was an auto, but the previous owner converted it to a manual.

 

There are a few things that are strange:

 

1) When starting the car (hot or cold) the power light on the dash flashes on and off and the car revs its self for about 10 sec. Seems to rev between 2-4000 rpm. (kinda annoying because people think im sitting in it reving it to show off :blink:)

2) Tick-over when cold seems to be about 2100 rpm which with my exhausts is really loud in queuing traffic! tick-over when warm seems to be 1500-1750 rpm. It does lower by about 250-500 rpm if i press the "off" switch for the heater/AC.

3) If I stamp on the "go" peddle, the car hesitates for a second, then goes like stink. That is the only way I can get it to produce the hesitation.

 

All other things work and seem to have no problems at the moment! My friend and I have given it a full fluids flush, changed filters etc and my new iridium plugs have just arrived :D

 

Nips

The first point is that the previous owner didn't remove all the auto parts, that flashing is coming from the auto box ECU representing an auto box problem code

 

Some one with more tech knowledge can answer the other points

The "power" light is connected to the fact it used to be an auto. My old one did the same after I converted it to manual. To the best of my knowledge, it causes no problems or anything - it's just a flashing light.

 

The hesitation is probably due to an air leak of some description.

So the power light/auto reving thing is due to the car still thinking its an auto? Can I change the ECU to a manual one to stop this? Im glad the auto reving wont hurt anything, but you should see the looks I get in Tescos petrol station after filling up and starting the car! :whistling:

Easiest & quickest way to diagnose & solve any issues is with a diagnostic (Consult) cable and appropriate software.

 

Is the neutral switch connected? If not, you will need to either fit a manual ECU or a manual chip to your auto ECU. The auto ECU map sets the timing at 25° BTDC when it believes the car is in gear & speed = 0mph, hence the increased RPM. Assuming no other issues, of course.

Only pipe I could find that seemed strange I have circled in red. Its got a stopper in the end. I need to change the "hosepipe" section too!

 

As said above the flashing light can be rectified by either disconnecting the auto box ecu, which is in the footwell next to the main ecu or you can remove the bulb in the dash to stop it annoying you.

 

The conversion normally requires you to connect the neutral switch wire to a pin on the main ecu to change the timing to 15 deg at idle, this is most likely the reason for the high idle, also you will need to make sure the TPS is set correctly 0.44v closed throttle.

 

All this info is in the tech faq section under Transmission/auto to manual conversion/wiring

 

The vac hose blocked on your balance bar would have come about from a delete, aiv etc and as long as its not leaking air, its fine.

Cool, thanks

Sorry to hijack the thread, I have idle issues occasionally (when cold idles at 1600 or so, eventually drops once warm) and my car was also a former auto which was converted to manual before I owned it.

 

Using datascan I seen the timing was at 25 BTDC, could this be the cause of the problem?

Idle when warm should be 15deg, when placed into gear you will see 25deg, as the revs are higher at cold start you will see a higher degree of timing as the engine is running quicker until warm, check your reading once up to temp.

Sorry to hijack the thread, I have idle issues occasionally (when cold idles at 1600 or so, eventually drops once warm) and my car was also a former auto which was converted to manual before I owned it.

 

Using datascan I seen the timing was at 25 BTDC, could this be the cause of the problem?

 

I've just checked the map you requested that I port over to your new Nistune set up, and it appears to be a mixture of automatic & manual tables. It does indeed have the same neutral timing as an automatic car, so this will be your issue if the timing is showing 25° BTDC when up to full temp and you haven't wired in your neutral switch.

 

Idle when warm should be 15deg, when placed into gear you will see 25deg, as the revs are higher at cold start you will see a higher degree of timing as the engine is running quicker until warm, check your reading once up to temp.

 

How it works:

The 300zx uses various 2D fuelling & timing compensation tables based on temperature for different scenarios. The increased timing is not a function of increased engine RPM, rather it is determined primarily by the ECU during the warm-up cycle (as is fuelling), it's not only the target idle speed that is higher when cold. Timing needs to be higher on a cold engine due to the richer mixture having a slower burn rate.

 

Manual & Auto gear timing compensation tables for the AC OFF condition are identical from -40°C to +50°C, at which point the auto levels off at 10° BTDC whilst the manual continues to 0° BTDC, hence the 25° BTDC (15+10) overall timing value for a manual-converted car with standard auto ECU and no neutral switch.

 

Manual & Auto gear timing compensation tables for the AC ON condition are identical from -40° to +50°C, at which point the auto levels off at 10° BTDC, whilst the manual continues to 0° BTDC until 95°C when it increases back to 5° BTDC and then from 100°C to 115°C it stays at 10° BTDC exactly the same as the Auto ECU.

 

There's quite a lot going on behind the scenes, it's easier to see it in action than to explain it in writing :laugh:

Edited November 26, 201411 yr by Noz