engine cuts out when afm signal is connected

KetsMcLets · Post by **KetsMcLets** » Sun Jan 17, 2010 1:41 am

I've got 1.06V @ idle on a z32 afm, don't know if that's standard?
When I connect the signalwire (green/black) to the afm the engine revs drop and a few seconds later it stops completely. Anyone knows what's causing this?
There's continuity between afm plug and ecu, connecting the second mass on the afm does nothing more, all the fuses and fuse links are good, the other 2 wires give battery voltage and nistune is set to z32 afm, but I'll recheck that later when I've got my laptop back..
Any more ideas? thanks!

the car is a '92 ca18det s13, with a h-dev stage 3 map on nistune except for 370cc injectors for breaking in the engine (don't have any 444cc's, only 560cc's)

TM_S13 · Post by **TM_S13** » Sun Jan 17, 2010 5:25 am

and you have the injectors well setup ? ?
if not, then you'll have overfuel problems... wich seem to be your problem...
the h-dev stg3 is made for 444 injectors, so you need to have them... else the car won't run properly...
get the stock map in there and resize the afm for the z32 and it should get better... I think...

Matt · Post by **Matt** » Mon Jan 18, 2010 12:22 am

You will need to resize from 444cc to 370cc otherwise it wont work. it will underfuel. you should use stock rather than throwing tunes on. Apart from mentioning Horsham Developments is on this forum also...

KetsMcLets · Post by **KetsMcLets** » Mon Jan 18, 2010 4:49 pm

it ran fine before, altough a little rich maybe.. The problem started when I switched back to z32 afm, in nistune the according setting are altered obviously... I've tried 3 afm's so far

KetsMcLets · Post by **KetsMcLets** » Wed Jan 20, 2010 4:31 am

tried another afm today, but still the same.. The original afm also doesn't work anymore (yes after afm's been altered in nistune)

This st3 map is because I still have that setup, only now with a bigger turbo and it's only to drive to the mapper, so definately no boost etc..

When I connect nistune and I keep the engine from stalling with the throttle the AFM dial says 1 point something volts (varies with the rpm's ofcourse) so the ecu def. sees the signal..
Without the signal wire connected it runs just fine, except for the 2K rpm limit..
I earlier had a wrong diagram for the z32 afm and it almost melted the 2nd mass wire, this probably has got something to do with my problem but I measured everyting and it sees voltage in the nistune AFM dial

I'm all out of ideas..

TM_S13 · Post by **TM_S13** » Wed Jan 20, 2010 9:34 am

why don't you just load the stock map, do the afm resize, and run the car in super low boost up to the mapper ?

KetsMcLets · Post by **KetsMcLets** » Wed Jan 20, 2010 9:59 am

I'm gonna try that tomorrow, if that doesn't work I'll put the original afm back in and try an original ecu..
Thanks

KetsMcLets · Post by **KetsMcLets** » Wed Jan 27, 2010 4:58 am

problem is solved, reloaded a st3 map and resized the injectors and all's fine now. Strange 'cause this should be the same map as I had previously..

Fordy · Post by **Fordy** » Wed Jan 27, 2010 7:43 am

becarefull you dont "MERGE" the map when connecting or doing anything with nistune

if you do merge your map with say a stock map it will change certain tables like injectors etc etc ...i found this out as i did the same thing

KetsMcLets · Post by **KetsMcLets** » Fri Jan 29, 2010 2:45 am

I never opened another map while trying, 'cause they were on a different computer but I'll watch out for that too in the future