Rich between shifts even with BOV recirc'd?

[HokieDSM]

I've noticed recently that when I'm accelerating and I upshift, my A/F gauge is reading full rich between shifts. My stock (crushed) 1G BOV is recirculated using the OE hose, albeit ducttaped up after the hose was torn up by rubbing on my ABS unit. I'm pretty sure that the hose is sealed - so why would I be running rich between shifts?

 

[Crazy E]

I have one of those disco dance A/F gauges in my car and it does the same thing. When I engage the clutch and shift the gauge flashes rich during the shift and then returns to normal. Im pretty sure it isnt something to be worrried about.

I have 2 theories:

1. I believe it could have something to do with the fact that you close the throttle while clutching which the TPS picks up and then the ecu responds by running the car richer (for whatever reason).

2. By closing the throttle to shift you are "shuting off" the air and maybe it takes the 02 sensor a second (while the engine speed drops) to respond to this and squirt less fuel.


, I have no idea if they are right (I have no basis for this, just critical thinking) so maybe someone that really knows can answer

 

[realhp=turbo]

I have read that the ecu is designed to dump a bit of extra fuel that it would definatly not burn, for cooling purposes. Youd have to look into a technical vfaq about blow off theory and the open and closed loop ecu. Basically I belive its normal.
mike

 

[TD05HTalon]

duct tape won't hold the hose - trust me! I had to try it for a day before I could get to the store and buy a new piece of hose after mine tore.

 

[HokieDSM]

duct tape won't hold the hose - trust me! I had to try it for a day before I could get to the store and buy a new piece of hose after mine tore.

Heh - I've been running the "duct tape mod" on two different OE hoses for a few months now.... I'd just replaced it with a new one with (what I thought were) a more secure taping - now my BOV sounds VERY interesting - although its certainly not venting at boost levels below 10psi - but above that, I get some interesting sounds coming from my car- never heard a BOV like it heh

 

[Jebus[tuning]]

Get a datalogger to see if you're REALLY running rich.

 

[DSM90AWD]

In every datalog I've done the O2s drop btw shifts to around 0V. Likely because the ECU is going from open loop operation (ignores O2V) to closed loop (manages fuel trims so O2s average .5V).

 

[HokieDSM]

I'll try logging it on my way to work this afternoon to see what it gives me.

 

[cuttheduck]

My ST fuel trims always show me going rich between shifts also. I am recirculated and all.

 

[DiamondStarM]

I'm gonna try to revive this thread before I start a new one. I seem to have a similar problem with running rich between shifts (I am recirculated). Before last week the a/f gauge would cycle as usual a little past mid-stoich and all the lights would go off when I let off the gas. Then out of the blue the other day I noticed the gauge would go a little into the rich zone when I shift, I also lost about 50 miles to a tank of gas. I check it out with the datalogger and my tune is still good. Anyone figure anything out?

 

[roni-wan]

same thnig here my aem wideband goes from 14.5 to 11.XX or 12.XX when i shift my bov is recirculated

 

[Defiant]

A/F gauges are only for filling a hole in a pod. Don't bother ever looking at one.