Tial BPV

[Bruce]

Does anyone have experiance with the Tial BPV's? I just installed one and am having problems with miss under boost. (where have I heard this before?) When the car miss's the fuel presure stays up but the Air fuel gauge goes lean. (cheep gauge off the o2 sensor)This leads me to the flex hose collapsing but it seams very sturdy when I try to squeeze it by hand and it still has the wire in it so? I disconected the vacume line to the valve and plugged the source and it still does the same thing. It sounds like the valve is working even with the vacume line off? Does this sound possible? In my mind if I remove the vacume source the valve should stay shut-am I wrong?

[Bruce]

OK ran codes and it appears I have an issue with the VAF. I tried to start it with the VAF disconected (figured that out prettty quick when it wouldn't start) could I have fried something by doing this? Codes say VAF out of range TPS out of range, air system inoperative. Codes 25,26,52,63,44. I will reset the tps in the morning.

[P.D.R.]

what spring are you running in the BPV? How much boost? & What's your vacuum at idle?

[Bruce]

I don't know the vacume but it came with the 11lb spring. 18lbs of boost.

[GAboySVO]

Bruce,

What is your boost/vacuum source for the BPV? It needs to be connected to the upper intake and the line as short as possible.

[Bruce]

The line is off the spigot for the FPR. I used that and took the FPR off a T in the large hose going to the vacume tree on the firewall.(turned intake) I am quite sure the Tial BPV is not my problem. The VAF is or something between it and the computer. I think I might have had a boost leak making the noise. Tightened the clamps on my fmic tubing and it sounds better but the miss issue is still large and the codes say there is a VAF problem. Funny thing is it pulled clean for the first run. After that it wouldn't work under boost. Still runs and drives fine in pre boost driving. How would one test the VAF?

[SVOeric]

A search will get you here....
vat test
VAF test

[Bruce]

Well today I tested the vaf and reset my base idle and tps. Disconected the battrey to clear codes. Took it for a drive and rechecked codes. 23 tps out or too high, 26 vaf out of range or trans oil temp out of range, 42 system rich. We don't have a trans temp sensor right?
When I drive it it runs fine for normal driving but goes completly lean (a/f guage goes dark) under boost? Before I blow a head gasket or worse I need to figure this out-any suggestions?

[Bruce]

Update today I confirmed the BPV is leaking under boost. After trying to come up with a way to pressure test it off the car I finaly pulled the vacume line to the BPV and put a plastic bag over the outlet hose and blew it to pieces. Problem found now to get a differant one. Worst part is now the car will be undrivable till the new one comes. I bought the Tial because I hadn't heard anything bad about them-go figure!

[Bruce]

Just to finishup here. I talked to the teck where I bought it and found the vacume line doubles as boost line to hold Tial valves shut under boost. The spigot for the FPR wasn't enough signal to keep it closed. Disconecting it was the wrong way to go. I pulled the intake and tapped it for a 1/4" line and ran it 8" to the valve and everything works now.