Drove from Jax to orlando this evening through some very heavy rain and had a couple of problems.

1) I had a few big spikes in A/F to very rich under light throttle. I normally cruise around mid to high 14s. If this is rich consider that my a/f sensor is after the cat, which i know is a problem. I am thinking, since i have a custom procharger like cold intake setup, the water was getting to the filter and the engine was cutting back to prevent water locking. I removed the intake setup at a gas station, and put the normal vortech filter on and after driving for 5-10 mins the problem did not reoccur even in rain.

2) I also noticed my a/f is all over the place during cruising. Is this normal? I saw variations from 14.1 to 15.0 occasionally and normally its bouncing around 14.5-14.9. I wasnt sure if this has to do with aftermarket injectors, are they spitting instead of misting, or could it be a o2 sensor with the gauge or what. Again, the o2 sensor is after the cat, if my readings are lean.

The problems i had were both under vacuum and between 2500-3k rpm. Basically slowly accelerating and cruise control at around 65-70mph.

Thanks for help, wanted to see if i have any problems i may want to address.

 

bouncing around is normal. If it stays more in the lean side then I would think u would have a problem.

 

good to know, i am correct that i should display leaner on gauge since it is mounted after the cat? The high flow cats i have alrdy had a bung, but i figure as long as i make sure things arent different serves same purpose....

 

I see high 14's cruising and my a/f w/b is after my welded-in cat. I guess it COULD be a bit leaner to get better mpg, but it crusies very nicely

 

Mike I think it will be all over the place depending on how much trottle you give it. Under load is when you should be concerned about a/f. You should do a run while at wot and see what it reads.

 

np, thanks, typically in WOT im more concerned at the rpms to shift, i see it get into the green and have seen it flash in the 11s and such, but hard to notice since this is typically 2nd gear and short lived.

 

uhm...shift? you have a 5AT.....

 

and? it has an manual mode that is very necessary when FI