Stalling/Rough Idle Issues

[Liger Zero]

Well, I just nought my first turbo car last tuesday and its a 1992 GSX. When I test drove it and everything before I bought it, the car ran fine. But after driving it for a little while the idle started surging a little, but I brushed it off and figured that it wasnt such a big deal. The guy told me that it started surging awhile ago so he replaced IAC or whatever with a junkyard one and then it stopped and that it only recently started again. Well, now its stalling left and right on me. I popped the hood and found that most all of my vacuum lines were missing so I went out and bought some and I used the diagram to hopefully hook them all up correctly again, still stalls. I replaced both plugs and wires, but still stalls. So my friend and I took a look at the BOV which is a Greddy(recirculated), and found that the BOV threads for the screw were stripped and that it was only being held in by the vacuum pressure, but on idle you can here the BOV valve leaking constantly. So, we took the screw out and plugged it with a small piece of rubber. It runs and idles fine when you first start it up and drive a little, then it starts stalling again, even worse! So with the screw removed from the BOV is it whats making my car stall? I have no idea what to do... Plus Im hitting some severe fuel cut problem at WOT around 5k in and gear 2nd and above. Any ideas guys? And yes I did search as much as possible in other threads to figure things out, but havent found exactly what Im looking for. Thanks in advance!

 

[All_Boost16G]

I would say thats proablly alot of your problem. With that screw missing its leaking boost right out, and when you shift the BOV is not doing its job. I had the screw strip on on me too, its very comman. You just take it off, and pull the top section off, and get a bigger helicoil set, and tap it and insert the helicoil, and a new bolt and nut. My had rounded out quite a bit, and i used a 5/16 helicoil and bolt and seems to work quite well

 

[Liger Zero]

I would say thats proablly alot of your problem. With that screw missing its leaking boost right out, and when you shift the BOV is not doing its job. I had the screw strip on on me too, its very comman. You just take it off, and pull the top section off, and get a bigger helicoil set, and tap it and insert the helicoil, and a new bolt and nut. My had rounded out quite a bit, and i used a 5/16 helicoil and bolt and seems to work quite well

oh ok, great! only thing is, I have it cureently sealed with a small rubber cap thing and its not leaking at the hole, but I was wondering if my idle is meesed up because there is no screw in there tightening the valve? It is recirculated so its not venting to atmosphere, but Im wondering if somehow it still causes my car to surge badly and stall?

 

[kevin keener]

check the fuel pressure regulator vacuum lines. If your loosing vacuum to the fpr solenoid
it will cause a lot of the problems you mentioned.

 

[Liger Zero]

check the fuel pressure regulator vacuum lines. If your loosing vacuum to the fpr solenoid
it will cause a lot of the problems you mentioned.

Well I just put all brand new vacuum lines on the car, so I dont think I would have a leak... When I bought the car it had no vacuum lines to the FPR, so I made sure I hooked that up right away... From what I can tell they are mounted on very tight so I dont think it would be leaking, but I will double check to be sure!

 

[Liger Zero]

OK, hopefully tommorow im gonna be able to work on my car and it wont be raining outside! So im gonna take a look at my BOV where the stripped threads are. From what I can tell they seem to be too stripped out to use teflon tape or anything to help the screw thread in, so I need to find a Tap & Die kit, but I have no idea where to find one. is there any recommended size I should re-thread it too or anything else Id need to know before I get involved with this project?