lumpy and rough on cruise?

[BigOne]

hi people,

our 3.0l RB30 5-speed has a miss when cruising/accelerating, the error code is 21, so it's either the crank angle sensor or the power transistor.
We had the intermittent stalling thing about 6 months ago, and put a new CAS in then.

EDIT (After a bit more research, the CAS is almost 2yrs old, and it is one of the cheap taiwanese ones, which can break down in a relatively short time, esp when they get hot, then the timing hunts between normally advanced and fully retarded.)

So, I suspect it's this, or the power transmitter, but I can't find a reliable way to test it, with gear on the home work-bench. I got another from a wrecker, and it's a little better, but not much.

Most of the other stuff has been replaced recently, like plugs, leads, dissy cap and rotor.

Please help. And how much should I pay for a transistor?

One other thing, our car has no oxy sensor. I think it goes in the bottom end of the cast part of the manifold, but ours only has a big hex blanking plug there. This means we cant tune the mixture with the blinking LEDs, right?

thanks
BigOne

[detox_nath83]

Miss could also be an earthing out in your ignition leads or a dodgey plug.. as well as injector problem, AFM problem CAS problem and various other things...

ok.. u need the oxy sensor in it.....
it will adjust itself to the right mix then u can fine tune if u like and get the LED''s blinking correctly...and adjusting the mix screw on the air flow meter as well with a multimeter will go through that later when you have a working O2 sensor

For Power Transistor (PT) on dizzy...

Grad a test light.
Positive to Battery and then on PT go to Neg(brown/red wire at PT. you light should Illuminate with Ignition Key Off. The coil is switched to ground through the PT during cranking.
If your test light flashes during cranking the PT is doing its job.
If not flashing the the PT has failed..
If light is constantly lit the PT has failed..

goodluck...

[BigOne]

thanks Detox,

do you know why my VL never had an oxy sensor?
Was it a NZ market thing? It has no cat converter either.
If I get one, will it plug straight into the 3 pin connector nearby?
cheers.

[detox_nath83]

yes it will go straight into the plug. against the firewall...
dont know why it does not have one... dont think it was a marketing thing either... meant to have one i guess,
does it use a lot of fuel, they cause increased fuel consumption if they are failing or not present at all..

[BigOne]

thanks detox,

I will look into getting an oxy sensor.

about the test light-

Grab a test light.
Positive to Battery and then on PT go to Neg(brown/red wire at PT. you light should Illuminate with Ignition Key Off. The coil is switched to ground through the PT during cranking.
If your test light flashes during cranking the PT is doing its job.
If not flashing the the PT has failed..
If light is constantly lit the PT has failed..

how can I make a test light? And I think you mean that I should connect it to the Neg(brown/red wire at PT while the PT is still plugged to the loom? by pulling the plug boot back, exposing the wiring at the back of the plug?
cheers
BigOne

[detox_nath83]

u can purchase one cheap at most servos and harware stores. as they have a resistor for limiting the voltage.

yes leave it plugged in man so it recieves the signal from the Ecu and CAS to switch..pull back the rubber boot as u stated..(rare really for a PT to fail... if your car is running means its working.. maybe on its way out)
Could be your coil starting to fail as well..
Have u given your CAS plug a good spray with Inox/wd40 etc. It is a common problem where the pins/plug corrodes. pull back rubber boot on CAS plug as well and check the spade connectors to where they are crimed to wires, common to corrode here as well,
I had 2 wired corrode off and snap on CAS plug but the pins and plug looked fine.

u can make a test light 2 12VDC Polarity/Test Light if u wanna

[delcowizzid]

nz vl's never had O2 sensors due to leaded fuel if you add the o2 sensor it wont work will be turned off in the tune ide say

[calais24/7]

I personally wouldnt f*** with the afm, they nomally shit themselves after you play around with them. someone did it to my car and i had to replace it cuase it ran like dogs balls

[detox_nath83]

i have tuned mine over 12 months ago with no problems
that cleared up the NZ thingy about o2 sensors cheers guys.




Had to replace it....... not just tune it to factory setting and be done with it?