Adjust fuel enrichment when ac, lights etc is ON

Discussions concerning the M7790 cpu

Moderator: Matt

Post Reply
ricardomendes
 

Posts: 40
Joined: Mon Aug 15, 2011 4:38 am

Adjust fuel enrichment when ac, lights etc is ON

Post by ricardomendes »

Hi, i would like to know how you guys adjust the fuel enrichment when the ac, lights, etc is ON.

the car is an s14 sr20det EDM and has z32, 550cc,etc and at idle and boost is has good AFR, but when we put lights or ac ON it pass from 15.1 afr to 11.2 afr at idle.

what table do you usually use to control this? i looked to enrichment parameters but no luck.

regards
Matt
Site Admin
 

Posts: 8961
Joined: Sun Jan 29, 2006 1:45 am
Location: Adelaide, Australia
Contact:

Re: Adjust fuel enrichment when ac, lights etc is ON

Post by Matt »

S14 ECU has a load input line. It normally uses that line to compensate for electrical dropping. However I'm not sure what table/constants it maps to

There is an injection 'voltage latency change' parameter which is used in latency calculations when working out voltage vs latency which can be changed

However I would suggest checking vehicle grounds firstly and checking how much voltage drop the ECU sees when you power those items on. My S14 doesnt drop the voltage much which means that you are trying to potentially tune around an electrical issue. The battery is probably on its way out if its dropping that much (measured at battery terminals)
ricardomendes
 

Posts: 40
Joined: Mon Aug 15, 2011 4:38 am

Re: Adjust fuel enrichment when ac, lights etc is ON

Post by ricardomendes »

ok matt will look at it tomorrow and update this.
skylinegtrhr
 

Posts: 301
Joined: Sat Jun 21, 2008 1:50 am
Location: Croatia
Contact:

Re: Adjust fuel enrichment when ac, lights etc is ON

Post by skylinegtrhr »

Also check voltage in Nistune because injectors are powered from same source if it is to low and battery is fine put bigger alternator, we use Quest alternator, very cheap even new http://www.ebay.com/itm/100-NEW-ALTERNA ... 0436387254
Post Reply