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

Fox Engine Or Transmission Knock 1990 5.0

  • Thread starter Thread starter alwaysbrokenfox
  • Start date Start date Nov 19, 2014
A

alwaysbrokenfox

New Member
Nov 19, 2014
1
0
0
Nov 19, 2014
#1
  • Nov 19, 2014
  • #1
was getting on fox, took it close to redline, shifted to 2nd did the same, push clutch in RPM's stayed up around redline, as if the throttle was stuck, but it wasnt i shut the car down, pull over restart it and its got a knock at idle AND under a load, that doesnt change after warmed up or anything of that nature. The oil is clean, oil pressure is good. I have compression in all 8 cylinders, spark plugs are all good, it sounds as if it's coming from the oil pan OR around the flywheel/tranmission area, i've never pulled a motor or tranmission and im nervous about doing that and wasting my time if it doesnt need it, has anyone ever experienced this before? Any suggestions? Pull the tranmission first, or is it even possible for the t-5 transmission to knock? Any help or ideas appreciated!
 

Boosted92LX

It's only an inch or two. What's the big deal?
15 Year Member
Dec 19, 2010
5,721
4,244
224
Nov 19, 2014
#2
  • Nov 19, 2014
  • #2
Sounds like you either A: stretched a rod bolt

or

B: beat up and damaged a lifter.


Since you say it sounds like it's coming from down low I'd say it's most likely A.
 

Micheal Nadeau

Active Member
Dec 30, 2013
258
32
49
Savannah, GA
Nov 19, 2014
#3
  • Nov 19, 2014
  • #3
Hmmm, mine did the same thing on the way home today, and I didn't even run it hard. Though mine may have seized up.
 

A5literMan

At least it is lumpy...
5 Year Member
Jul 30, 2011
4,674
2,343
194
Illinois
Nov 20, 2014
#4
  • Nov 20, 2014
  • #4
That's a no good! I'm with boosted-rod bolt is my guess. I've never heard a trans "knock". Grind,lock up,not go into gear,etc would lead me to the trans but a "knock" in the lower end/oil pan area is very likely the engine.
 

FoxMustangLvr

I love my Pimp
SN Certified Technician
Oct 14, 2012
4,968
3,514
204
Spokane, Wa
Nov 20, 2014
#5
  • Nov 20, 2014
  • #5
Because you said the RPM stayed up toward red line with the clutch in makes me think there's something wrong in the valve train. Before you start thinking about pulling your engine and trans out I would remove your upper and lower intake manifold and pull your VC's off and inspect your rocker arms, springs, pushrods and lifters.

Have you had any recent work done to your engine? New top end? Any aftermarket engine parts?
 
Reactions: elarm1

Micheal Nadeau

Active Member
Dec 30, 2013
258
32
49
Savannah, GA
Nov 20, 2014
#6
  • Nov 20, 2014
  • #6
The throttle body most likely stuck open (Professional Products??) Mine did the exact same thing last night. Started it this morning, no knock.......until the engine temp came up.
 
You must log in or register to reply here.

Similar threads

H
Ongoing Battle With Hydraulic Lifters
  • hailer06
  • Jun 8, 2026
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
Replies
7
Views
223
1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- Jun 9, 2026
Noobz347
K
TKX Transmission Shifting Problem
  • KWC156
  • Jun 23, 2025
  • Other Auto Tech
  • 2
Replies
21
Views
2K
Other Auto Tech Jun 13, 2026
427nostang
4
Drivetrain 83’ Glx convertible C5 Trans help!
  • JacksonJared2113
  • Dec 25, 2025
  • Fox 5.0 Mustang Tech
Replies
2
Views
371
Fox 5.0 Mustang Tech Dec 26, 2025
JacksonJared2113
6
Hey all,I’m putting together a 302 for my 1968 Mustang and wanted to post the combo + some questions to make sure I’m not missing crucial
  • 68_Disgustang
  • Feb 22, 2026
  • 1965 - 1973 Classic Mustangs -General/Talk-
Replies
4
Views
793
1965 - 1973 Classic Mustangs -General/Talk- Jun 20, 2026
gray owl
G
T
  • Locked
1990 2.3L automatic - real bad engine sputtering
  • the_steve_randolph
  • Jun 13, 2024
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
Replies
10
Views
1K
1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- Jun 14, 2024
the_steve_randolph
T
Share:
Bluesky Email Share Link
  • Mustang Forums
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
Menu
Log in

Register

  • Forums
  • What's new
  • Media
  • Resources
  • Contact
  • Sponsor
X

Privacy & Transparency

We use cookies and similar technologies for the following purposes:

  • Personalized ads and content
  • Content measurement and audience insights

Do you accept cookies and these technologies?

X

Privacy & Transparency

We use cookies and similar technologies for the following purposes:

  • Personalized ads and content
  • Content measurement and audience insights

Do you accept cookies and these technologies?