rb20det knock sensor & CAS questions

[Black_label_240sx]

Hello
Have a problem with car when the car starts up cold the timing is retarded all the way till it hits above 3000 rpm then pulls like normal, then when it heats up to 140 f or higher the car runs like normal.
Now, once it warms up and the timing goes back to normal it starts dying at lights. It gets way worse when I turn my lights on ( stock lights ). Seems like more load on the motor from the electronics makes it die, but its only been doing this a select few times.
Checked the ecu, got a code 55 - so all clear
checked the knock sensors, got 500 k ohms for each of them. So they should be good.

Now, when we went to swap in an AEM cas wheel, to use with the 6620 box, the stock wheel got tweaked a bit, well.
the stock cas wheel ended up going back in as AEM didnt setup their EMS for RB series motors to use MAFs only maps so until the MAP sensor comes in im stuck using the stock CAs wheel.
when we put the stock cas wheel back in is when this all started, is this a coincidence or ?


thanks!

[Black_label_240sx]

Bump

Heres what we found doing a CAS check, took the cas out, spun the wheel with the ignition on run, injectors and coils fired, fuel pump turned on.
Checked the CAS signal wires, when the cas was not spinning the signal ( green wire ) read 5 volts, when spinning the voltage went all over the place
the second green wire, didnt read any volts at all, even when being spun
Anyone know if this is a correct way to test or an exact right up of how to check a CAS
Also, will a vg30dett cas work in an rb20det?
thanks

[Yellow4g63]

I think they might be different man. I'm waiting on my map sensor and AIT sensors before I install my AEM 2.

[Black_label_240sx]

what might be different ? the CAS wires or the problem in general
how do you test the CAS signal wires then? with like OHMS or VOlts ?

[Carl H]

the problem isnt with the cas or the knock sensors, you need to check the idle switch on the tps to make sure its engaging.

rb20 ecu relies on this to run properly, if its not set from the getgo on first start everything runs like crap

[Black_label_240sx]

okay, ill def check that.
is there a voltage is resistance that I should check it for?

[Carl H]

its a make or break, make sure the sensor has continuity on the plug on the tps body. bottom two pins iirc.

[Black_label_240sx]

alright ill check that.
would that cause the timing to retard on a cold start though?

[Carl H]

mhurm.
also start signal should be connected so the motor knows its going thru its startup sequence.

[rswails]

Thanks Carl. I have this exact problem and I posted about it before here what-can-cause-a-flat-spot-t509742.html. This is awesome if it fixes the issue. I am pretty sure my idle switch works though but I'll check again. I have already replaced both knock sensors because in a different post that had my exact problem also, they said that fixed it :-(