Nistune Forums

I have a problem with the k-constant, has the first start, the AFR ratio is very low, should I go back to 370+ K instead of 288 stock. The car is completely stock, only the AIV has been removed from the exhaust line. the AFR was correct before installing the nistune card .
I have calculator version that requires to remove of a 28 pin eprom ,23710-47P10 REV 14
all versions have k-cont 288 for tubo and 411 for atmo .
Any idea?

it's probably the AIV ...

cold Kconstant must be increased to have consistent AFR , when hot ,288 and I am correct. the solution can be will enrich the iddle cold way to compensate?

Make sure K constant is set for good AFRs when the engine is warm

When engine is cold, the ECU will use the enrichment tables to add more % fuel to make the mixture richer during warming up

at cold start the afr is too poor ( 16-17/1) but 288 the afr warm is ok on road , but after few second at iddle the afr is too poor ,
more forums have the same problem after remove AIV (saccade problem at idle):
http://www.aus300zx.com/forum/showthread.php?t=291983

idle should be fine after AIV removal.

you probably have a vacuum leak somewhere or connected/bypassed a hose from the old AIV system incorrectly ?

-Eric

problem ... is not my car , and is not me removing AIV .
I helped a friend to install the eprom and parameterize the map.
it remains the AIV solenoid,and 1 hose closed (middle) and the other two still connected.