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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • Fox 5.0 Mustang Tech

engine trouble, vacuum leak maybe?

  • Thread starter Thread starter mr_tinkertrain
  • Start date Start date Apr 11, 2004
M

mr_tinkertrain

Member
Dec 14, 2003
151
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Hot Springs, AR
Apr 11, 2004
#1
  • Apr 11, 2004
  • #1
well for you guys who remember, i posted a thread about idling problem on my high mileage 5.0 awhile back. I have since gotten a timing light, set it to 12 w/o pinging, and adjusted tps to .990. But there are still problems with popping at acceleration and with the idle. According to this repair manual i bought the problem could be a vacuum leak. Does anybody know of any likely places i'd have a leak, or know a way i could go about searching for leaks. Is there a kit of new hoses I could buy, any help is appreciated.
__________________
 

ECU5.0

Banned
Jan 10, 2004
1,803
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raleigh, nc
Apr 11, 2004
#2
  • Apr 11, 2004
  • #2
just check all the vacuum lines going to the intake and if that doesnt turn up anything than check the intake itself (upper to lower) or throttle body for leaks. any air that gets into the engine after the MAF will mess with how the engine runs
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
34
129
Apr 12, 2004
#3
  • Apr 12, 2004
  • #3
check your vacuum. the tree on the driver firewall is easy to access. should be 15-20 inches at idle.
however, in my experience, popping at halfway hard acceleration is not a vacuum issue, as there is little vacuum while accelerating halfway hard. vac leaks tend to create some popping on deceleration along with hanging idle (takes a little bit for the idle to settle down).
just my thoughts. good luck.
 
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