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Engine Missing and popping under acceleration cold or hot

  • Thread starter Thread starter old_blue
  • Start date Start date Apr 11, 2021

old_blue

15 Year Member
Nov 3, 2003
1,783
282
124
Apr 11, 2021
#1
  • Apr 11, 2021
  • #1
Stock 88 5.0 5 spd with an exhaust. Just did spark plugs. Cap and rotor are fairly new as well as spark plugs. New fuel pump and filter. New o2 sensors. Distributor was rebuilr a few years ago.

car has a slightly rough idle. I Pulled codes and has a lean code. I was thinking TFI but it pings, pops and misses even when cold. No vacuum leaks. Not sure what else to check.
 

old_blue

15 Year Member
Nov 3, 2003
1,783
282
124
Apr 11, 2021
#2
  • Apr 11, 2021
  • #2
The car did sit for a year or more. The fuel sock was disinegrated and clogged the old pump.
 

RaggedGT

Been here over a DECADE and still no CT
Mod Dude
Jul 20, 2014
4,737
3,186
203
Taylorsville ky
Apr 11, 2021
#3
  • Apr 11, 2021
  • #3
Long time no see.. stupid question time, did you verify timing? Verify fuel pressure? Possibly a restriction in the fuel lines from the old gas?
 

old_blue

15 Year Member
Nov 3, 2003
1,783
282
124
Apr 11, 2021
#4
  • Apr 11, 2021
  • #4
Yeah. Im more of a visitor these days checking in from time to time and see the projects on here. Mostly working on my f100 and driving my ‘14 gt lately. I also picked up a project ‘68 camaro.

I did verify timing but not the other two. Ill pull fuel lines at the tank to verify blockage and blow them out then check pressure. Maybe clogged injectors???
 
Reactions: RaggedGT

RaggedGT

Been here over a DECADE and still no CT
Mod Dude
Jul 20, 2014
4,737
3,186
203
Taylorsville ky
Apr 11, 2021
#5
  • Apr 11, 2021
  • #5
Well, Welcome back,even if it’s only temporary lol. I wouldn’t rule out a sticky/varnished up injector-or same in the fuel lines. When you changed the pump, was it the whole assembly? Or just the pump itself?
 

old_blue

15 Year Member
Nov 3, 2003
1,783
282
124
Apr 11, 2021
#6
  • Apr 11, 2021
  • #6
Whole assembly. The old pump ate the sock and it was all nasty. Cleaned it out and dropped a new assembly in.
 

old_blue

15 Year Member
Nov 3, 2003
1,783
282
124
Apr 14, 2021
#7
  • Apr 14, 2021
  • #7
New tfi will go in this weekend. Tied up this weekend with life stuff so not much work will get done. I think i mentioned the 56 f100 in the past but i was informed there wouldnt be much interest so i left it alone. Its had a few changes like most projects like different power plants and suspension/cross memeber changes. Currently it has a ‘18 f150 coyote motor 10r80 sitting between the frame rails. I boxed the frame for a little more rigidity. Had a wiring harness made and the computer reprogrammed to remove vats.
 
Reactions: RaggedGT

RaggedGT

Been here over a DECADE and still no CT
Mod Dude
Jul 20, 2014
4,737
3,186
203
Taylorsville ky
Apr 15, 2021
#8
  • Apr 15, 2021
  • #8
I seem to remember following along with that truck-wasn’t it originally getting a crown Vic front clip and a mod motor?
 

old_blue

15 Year Member
Nov 3, 2003
1,783
282
124
Apr 15, 2021
#9
  • Apr 15, 2021
  • #9
Thats correct. Still has the crown vic k member but the 4.6 is long gone. I got an 12 coyote motor but sold that to fund another project. Then i found this 18 f150 motor and trans with 6k miles for $4500. Couldnt pass it up.

I found the issue with the foxbody. Crossed wires #2 and #7 at the dizzy. Car runs great now.
 
Reactions: RaggedGT

RaggedGT

Been here over a DECADE and still no CT
Mod Dude
Jul 20, 2014
4,737
3,186
203
Taylorsville ky
Apr 16, 2021
#10
  • Apr 16, 2021
  • #10
old_blue said:
Thats correct. Still has the crown vic k member but the 4.6 is long gone. I got an 12 coyote motor but sold that to fund another project. Then i found this 18 f150 motor and trans with 6k miles for $4500. Couldnt pass it up.

I found the issue with the foxbody. Crossed wires #2 and #7 at the dizzy. Car runs great now.
Click to expand...
Glad it was something simple to fix.
Coyote swapped pick up sounds pretty sweet, last I remember -it was still pretty much in the disassemble/planning stage right?
And..... Didn’t ya have a ‘60-sumthin’ Mustang project going too?
 

old_blue

15 Year Member
Nov 3, 2003
1,783
282
124
Apr 16, 2021
#11
  • Apr 16, 2021
  • #11
yeah. It was in a lot of pieces. But the can and bed are back on it.

I recently sold one of my 65 mustangs when I bought my 68 camaro. I still have my wifes 65 mustang that had a rebuilt roller 302. Was going to go T5 but now she wants an auto so im going to sell the manual.
 

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