I just installed my SC about 2 weeks ago and it's been running flawless until the other day we did a valve adjustment and now when the engine is cold it surges from 1000-1500 until the engine is warm. I have also noticed that it has a small stutter in it like it's missing but it's not as bad as a true miss and also when I start to go after stopping it bogs out like it's flooding. I have a GSS342 255lph Walbro and it's been fine up to that point. Is the fuel pump to big? I see it's running about 48psi at static and around 80+ under boost. I know this is to high for the stock boost and I don't have a FPR to adjust it yet. Should I put the stock fuel pump back in and see if it helps?

Does anyone have any idea what could possibly cause this? I don't think the valve adjustment would cause the surging but it started do this right after the valve adjustment.. I have checked vacuum lines, plugs and everything and found nothing wrong.



Modified by Y2KEBPSI at 12:34 AM 8/4/2004

 

What are your mods? also..what are you using for fuel managment?

 

check here http://www.hostboard.com/cgi-b...f/110
this is a JRSC only forum you will find the people over there to be much more friendly for SC advice trust me. All you will get here is BUY A TURBO

 

Yeah I am a member over there too.. I have all the basic mods and am using the JR FMU for the fuel management.

I am also running 48psi at static and 80+ under boost.. I need a FPR to turn that **** down..

I am throwing a CEL for my test pipe so I am going to go out in a little bit and see if it's throwing anything else besides the o2 sensor.

 

Update..

I am throwing 3 codes.

61 = Primary o2 sensor
67 = Secondary 02 sensor
45 = Fuel system to rich or lean.

Would this cause the problems I described?

 

Do not run the stock fuel pump.

What are your fuel pressures at:

Idle ?
0 psi ? (disconnect the hose going to the fpr and pinch it)

Sonny

 

I've heard that doing a valve adjustment too tight can cause problems. I can't remember what exactly, but since your problem started immediately after your valve adjustment, I would have to say go back and check that. Maybe loosed them up a bit.

 

I am also running 48psi at static and 80+ under boost

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Y2KEBPSI &raquo;</TD></TR><TR><TD CLASS="quote">I am also running 48psi at static and 80+ under boost</TD></TR></TABLE>

Just so we're clear, how are you testing to get your static pressure?

Sonny