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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
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idle climbs to 4,000 rpm!?!?!?

  • Thread starter Thread starter fastang67
  • Start date Start date Sep 28, 2004

fastang67

Founding Member
Jun 9, 2001
112
1
18
Kingston NY
Sep 28, 2004
#1
  • Sep 28, 2004
  • #1
Hey guys I'm about to give up. I have a 91 lx coupe 40 overbore 302. twisted wedge heads, o-ringed, cobra intake w/1inch phenolic spacer, bbk 255 pump, aeromotive adj fuel press. regulator. 24 lb injectors. msd 6al, & coil autolite 2294 plugs .055 gap. 70mm throttle body, & matching mass air, bbk cold air intake. no smog equipment at all.

I had this combo together running good for 2 months after building it. Then I blew a head gasket (overheated due to electric fan issues). Since then I put her back together as it was except for the plugs (They were stock autolite, but I forget the number) and i put a rebuilt (cleaned & tested) used set of 24lb injectors in. (real old 24lb injectors came out) started it up and it went to 4,000 rpm. ( a good sounding healthy 4,000)

I found fuel in my vacuum line to the regulator, so i disconnected it from the intake & plugged it. It doesn't climb to 4,000 with the spout jumper removed & the timing at or around 0-10 degrees but it runs rough. starts to climb again if I get close to 14.

I can't confirm exactly where the timing is at because of the way it runs, the marks appear erratic with the light, sometimes off scale, but never still enough to measure. (with jumper out)

I haven't found any vacuum leaks, and my fuel press is around 40 psi without vauum. It appears to be a real lean mix, my ceramic headers begin to glow after 1 minute. but engine temp remains low.

I suspect a combination vacuum leak, fuel leak (reg to intake) problem, but can't isolate it becuase of the glowing headers. This setup ran great before the plugs & injectors got swapped as well. I tried a 19lb mass air meter to see if I got jipped on the injectors, but it didn't help.

Any ideas are greatly appreciated, Greg
 
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