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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • 1994 - 1995 Specific Tech

no luck with gt-40 upper and lower

  • Thread starter Thread starter rockyracoon
  • Start date Start date Jan 10, 2019
R

rockyracoon

10 Year Member
Nov 23, 2005
874
27
49
margate NJ
Jan 10, 2019
#1
  • Jan 10, 2019
  • #1
Tried 3 times (3sets of gaskets) and car still wont even stay running. have to keep on the throttle for it to stay running and it seems like it is running really bad.

used guide studs for both upper and lower, no rtv under rubber rails. dabs at corners where heads, manifold and block conjoin. used a smear of blue rtv around coolant ports.

upper and lower were from a 97 mountaineer, purchased a trick-flow elbow, made sure all vacuum lines were connected but still no luck. im in the process of putting stock manni back on.
Gaskets used were for a 97 mountaineer. seemed to me that there was a major vacuum leak. did have the dizzy in 180* off at first but reconciled that. any ideas greatly appreciated.

Car ran great after I installed 4.10 gears but just wanted more power.
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,249
17,932
224
Massachusetts
Jan 11, 2019
#2
  • Jan 11, 2019
  • #2
Before you rip it all apart, I would build a smoke machine and do a smoke test.

https://www.stangnet.com/mustang-forums/threads/smoke-machine-for-vacuum-leak.907314/

Usually when ive done lower intakes, I've used stud guides, use the china wall gaskets but lay a think strip of RTV down amd gobs in the corner, and then a small rtv circle around the water ports. Then I set it down and tighten.

If you suspect a vac leak, i'd smoke test to determine where your vac leak is as it can help you pay more attention to the end seals if they are the culpits.
 
R

rockyracoon

10 Year Member
Nov 23, 2005
874
27
49
margate NJ
Jan 11, 2019
#3
  • Jan 11, 2019
  • #3
Ok thanks much.

I may end up building the smoke test machine.
 

Noobz347

Stangnet Facilities Maint Tech... Er... Janitor
Admin Dude
Jan 4, 1985
43,048
21,213
234
Box behind Walmart
Jan 11, 2019
#4
  • Jan 11, 2019
  • #4
I would run the "Cranks but Won't Start" checklist:

https://www.stangnet.com/mustang-fo...-checklist-for-fuel-injected-mustangs.787471/
 
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