If your hho cell are high efficient produce (less than 45 c)low temperature quality gas, then try to lower the amp you use if you work without an EFIE.
Slowly lower the amp you use if the check engine light on.
Test until the check engine light off then you get suitable amp for HHO generator which suit you car engine.
First try with 15 A,then 10 A, then 5 A, then 3 A etc till get the best Amp.
of course high amp=higher gas production however it may not suit all engine.
Run Green and be happy.HHO= Hydrogen+Oxygen
Little production were help fuel to burn more efficient,but if too much it trick your car 02 sensor...Think?Then you understand What I mean.