Fix Low RPM Timing Surge (Stall Saver)

The $EE code contains a very odd type of ‘stall saver’ routine that uses timing advance only. This exists in MANUAL transmission calibrations only.

This tends to work alright on a stock engine, but on modified vehicles, it can cause major timing fluctuations. Although I’m not really sure why it glitches out so badly, it probably has to do with the fact that it was configured for a stock timing table and the operating range of the stock cam.

Symptoms include logging up to 10 degrees of randomly flucuating timing advance during gentle coasting or decelleration. This occurs in varying intensity as the TPS becomes very low, and rpm dips below 1600rpm on f-bodies and 1400rpm on y-bodies. It can show up as a bucking/surging or a general lack of drivability.

Some people mistake the issue as simply being too far outside of their cam’s operating range, when in fact their car would decellerate smoothly if it wasn’t hitting the stall saver bug.

Simply pushing the clutch in and coasting in neutral will reveal the error in logs. The stock configuration makes the surge less obvious on y-bodies, as they use roughly half as much stall saver…

Note the following log when TPS drops to zero, and RPM tips below 1600, which is the stock MAX RPM threshold:

To alleviate this problem, disabling or reducing the effect of the stall saver is necessary. I reccomend disabling it entirely. I have logged many hours of driving with it disabled and suffered no stalls or other ill effects, and noted a substantial improvement trying to drive in slow moving traffic.

Download my latest XDF file and alter the following parameters: