Rich idle after 10 to 15 seconds at 14.7

[Lok]

Does yours stay at 14.7 permanently?

After coming to a stop mine will stay at 14.7 but then move to 13.5 after 5-10 seconds.

[redtoptech24]

After Dealing with this same issue with 2 different s13 redtop swapped cars for the last 8 years I believe that I have finally figured out the cause. Last weekend while making a harness for a friend (redtop into s13) I was going over the ECU pinout and removing unnecessary wires from the ECU connector. Though Ive looked over the The connector pinout countless times this was the first time that I noticed pin 105. It is a red wire with white tracer and it is labeled as "fuel pressure control module." I cant find any info regarding this component however based on my experience with other vehicles use of similar nomenclature I assume that this module is used to reduce the voltage to the fuel pump during idle. unfortunately even if I could get my hands on one of those modules, I couldn't make use of it as ive long since hardwired my pump to a relay controlled by the factory FP power wire.

[Matt]

Details will be in the FSM (Factory Service Manual) but this is usually to adjust fuel pressure at idle. I've not looked into it that much since we normally direct wire relays for fuel control into 104 and high pressure fuel pumps