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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
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popping and jerking

  • Thread starter Thread starter blkstangman88
  • Start date Start date Jul 9, 2004

blkstangman88

New Member
Apr 6, 2004
646
0
0
Jul 9, 2004
#1
  • Jul 9, 2004
  • #1
ok when ever im on the free way doing about 70, when i press the gas about 1/2 way my car pops, backfires and jerks, but when i put the gas to the floor it runs fine with no problem......my car does this in town also....any ideas y?
oh ya i just put new plugs in about a months ago, there ngk and my times set at 13 btc
 

bmorrisj

Member
Sep 26, 2003
449
0
17
Buena Park, CA
Jul 9, 2004
#2
  • Jul 9, 2004
  • #2
check fuel pressure....make sure your plugs are gapped properly.
 

blkstangman88

New Member
Apr 6, 2004
646
0
0
Jul 9, 2004
#3
  • Jul 9, 2004
  • #3
plugs are at .54 like the book says and napa told me........just put in a new fuel pump about 4 months ago. where is the stock fuel pressure regulator? can it be adjusted if it it the pressure?
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
34
129
Jul 9, 2004
#4
  • Jul 9, 2004
  • #4
pulled codes? at part throttle, the EGR should be functioning. if it is malfunctioning, that could cause some havoc (or if it is runnin intermittantly at part throttle, which would be incorrect).
what is your vac reading like? a healthy stock-ish motor should have around 15-20inches at idle. under WOT, almost zero. at part throttle, somewhere in between.

while i think Morris has good stuff to say, i dont agree with him on this one. if you are running decent at WOT and idle, i would not necessarily have thought of the Fuel pressure being an issue.
that said, im not real bright, so: the stock FPR is behind the TB. it is not adjustable in stock form. an adjustable unit is the easy way to dial in more pressure. i dont see mods in your sig that would justify such a purchase. if you pull the vac line on the FPR and find fuel in it, then do replace it - that is a sign of a bad FPR (bad diaphram).

my ramblings. good luck.
 
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