I need some help, what does the PA (atmosheric sensor) show on your cars using neptune? Mine shows 0.2-0.3psi, which doesn't seem right. I would really appreciated it if you guys could just take a quick look and see what yours shows.

 

Mine shows correct atmospheric pressure in mbar. It was 980 last time I tuned. I don't know how that sensor scales, but is it possible you're displaying sensor voltage and not psi or some other pressure unit?

 

Okay, it shows 0.2-0.3 psi. I looked an 980 Mbar is 14.21 psi or 28.94inHG. So it should read something. Thanks I really appreciate it. Anybody know why it's not working, but there isn't a CEL? Can you test the PA sensor in the ECU?

 

It is working... I explained this to you in email. 0 is atmospheric pressure at sea level, one atmosphere of pressure. 0.2-0.3 means you're getting more than one atmosphere, which means you're probably below sea level or have some storm system that's varying the barometric pressure in your area. It's shown in mBar until 0psi is achieved... same as the map sensor when you have mBar set for vacuum units and psi set for pressure units.

There's no mystery here.

 

So what do you think the problem is? It's the same engine, and I reused all sensors, distributor, wire harness, etc...The last engine ran great on the P29 base map. And now A/F ratios are all over the place. I tried recalibrating my LC-1.

 

Something other than the atmospheric pressure sensor. You have the tools to datalog and see what's not correct... or correct it if everything is working properly.

 

Well all sensor values seem right, but how do you explain that it was perfectly fine one day, then I change out the engine (same DOHC ZC, with same cams, same intake, same distributor and sensors) and then the A/F are all over the place. I had to add +10 to +15 to the fuel values to idle around 14.7:1 when warmed up. Normally it would start at 11.5:1 when cold, then as it warms up it goes to around 14.7:1, but when I first started it up it the A/F went to 17-18:1 after a few minutes. I guess I will just add fuel in all those areas and hopefully there isn't anything else wrong. Thank you.

 

I think you'll be fine with a touchup to the tune.

 

ZCHonda, you have a PM.