4agte no spark

[themaleman]

ok got no spark
tried jumping it still no spark
all terminals ect are sweet
tried diagnostics and it gave me error 12,

12 RPM Signal
Diagnosis
* No "NE" or "G" signal to ECU within 2 seconds after engine has been cranked.
Trouble Area
* Distributor, or CPS, circuit
* Distributor or CPS
* Starter signal circuit
* ECU

the car is a map sensord ae92 gtz

can any1 tell me what i should do next, as in where do i check for the mentiond signals ect

cheers

[matt dunn]

Try another CAS/Dist sensor.

[themaleman]

is replacing the cas as simple as removing the old 1 and puting in the new 1? or is there a procedure i must folow to set it or something? thanks

[Rick]

To rule out the wiring you can use a muiltimeter and check the continuity between the CAS and the ecu plug.

"G" is pin 16 on the "Z" plug of the ecu.
"NE" is pin 1 on the "a" plug of the ecu.

[Rick]

[1hypo3]

ok got no spark
tried jumping it still no spark
all terminals ect are sweet
tried diagnostics and it gave me error 12,

12 RPM Signal
Diagnosis
* No "NE" or "G" signal to ECU within 2 seconds after engine has been cranked.
Trouble Area
* Distributor, or CPS, circuit
* Distributor or CPS
* Starter signal circuit
* ECU

the car is a map sensord ae92 gtz

can any1 tell me what i should do next, as in where do i check for the mentiond signals ect

cheers

Can u get a hold of a scope?
ideally you need to scope ne and g signals for output

[themaleman]

Can u get a hold of a scope?
ideally you need to scope ne and g signals for output

can u please explane, what dose a 'scope' look like?

[matt dunn]

Scope is like a high speed graphing multi-meter.

Has a screen like a heart rate monitor you see on TV.


And that diagram for replacing the CAS is for a dist'd one,

a CAS can be done by the same method but there is easier.
Take the top off it, ( 3 x 8mm bolts, IIRC)
turn the engine by hand until the single top tooth lines up with one of the sensors exactly,
remove it and fit the new one in so that the same part lines up with the same sensor in the same position.
You will need to get the teeth lined up and the dist twisted to the right place,
then do it up and put the lid back on.

You can check the CAS with a multi-meter if you know what you are doing, both resistance check and for AC voltage output,
but cant remember which wires are which from memory.

[KinLoud]

was it running and now it doesn't go?

If it did go and now it doesn't what happened?

did you fiddle with anything?

Ken

[themaleman]

well ive changed the engine and turbo, since then it hasnt started. about a month befor the old turbo blew i had been go-carting, and after the races as i left auckland raceway the car randomly died like 15 meters down the road, tried jumping it then and there with no joy, so had to tow it home. tried jumping it a day or 2 after that and it started sweet as as was running sweet since. we presumed it must have been flooded.

so im not sure weather its the same problem as when it died and woudnt start

i am certain everything is hooked up sweet. tho i need a knock sensor as the last 1 broke. hopfully get 1 from a wreckers on tuesday.

i have the cas from the previous engine so could change it. tho id like to be sure thats wat the problem is before i replace it

[l1ttle_d3vil]

have you got decent earths from engine to chassis? put another one on just incase, I had a dodgy one a while back so the engine sensors (inc dizzy) weren't earthed properly which meant no spark, no engine rpm etc.

[themaleman]

yea baterys in boot, but weve run fat cable to the gearbox and to the chassis

[themaleman]

ok changed the cas, still no spark and still getting error 12

[themaleman]

error 12 RPM Signal
Diagnosis
* No "NE" or "G" signal to ECU within 2 seconds after engine has been cranked*

would that stop the engine from firing?

To rule out the wiring you can use a muiltimeter and check the continuity between the CAS and the ecu plug.

i can get hold of a scope,
do i need to strip the loom by the ecu to check for signal on "NE" and "G"?

thanks for the input thus far

[1hypo3]

error 12 RPM Signal
Diagnosis
* No "NE" or "G" signal to ECU within 2 seconds after engine has been cranked*

would that stop the engine from firing?

To rule out the wiring you can use a muiltimeter and check the continuity between the CAS and the ecu plug.

i can get hold of a scope,
do i need to strip the loom by the ecu to check for signal on "NE" and "G"?

thanks for the input thus far

Yes no Ne or G signals will stop engine from firing!
Use the scope and back probe Ne and G at computer if you have no signal check at CAS by back probe that way you check wiring as well at same time.
If you get a strong CLEAN signal at computer i would try another ecu.
I would start out by setting scope to around 1vdiv and 10ms for the trace and adjust if needed

[themaleman]

changed ecu now shes sweet!! thanks people for the input!