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White smoke from passenger side firewall???

  • Thread starter Thread starter Vondy
  • Start date Start date May 28, 2022
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Vondy

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Nov 28, 2021
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May 28, 2022
#1
  • May 28, 2022
  • #1
Hi there, I have a 1990 LX 5.0 and the last couple times I've started it I've noticed white smoke coming from the back left of the engine bay. It almost seems to be coming from the transmission tunnel or the lower part of the motor.

I've also heard that this could possibly be a heater core leak. Any way to test it? And if there are any recommendations please let me know!
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
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May 28, 2022
#2
  • May 28, 2022
  • #2
Check the condensation drain at the bottom of the firewall and see if you see any green liquid dripping out and onto your exhaust
 
S

Specracer

Active Member
Nov 24, 2020
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SE MA
May 30, 2022
#3
  • May 30, 2022
  • #3
You will want to address this soon, by changing the core, or bypassing it, before it soaks your interior carpet. 3 options for replacement, the off shore aluminum replacements available at all of the suppliers (LMR Rock Auto etc), find a NOS OEM, or have a recore done. Ive done 2 in the last year or 2, one with Aluminum, and one with a recore. I was not super happy with the quality of the aluminum which was the 1st one I did, so found a local shop to perform a recore.
 
V

Vondy

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#4
  • May 30, 2022
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Thanks for the replies. I checked today at the drainage port of the heater core and there is no visible fluid coming out. Today I realized that the smoke kind of smells like ATF. Is it possible that the dipstick is leaking onto the exhaust or something?

Additionally, the smoke isn't directly under the heater core drain. It's more towards the actual engine block. I have also discovered what seems to be ATF inside my radiator, which has coagulated into a thick sort of orangey/brown foam towards the radiator cap. Any clue?

I've attached an image to help clarify where the smoke is located. Thanks a ton.
 

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Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,229
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Massachusetts
May 30, 2022
#5
  • May 30, 2022
  • #5
The aod trans cooler lines also are directly over the exhaust. I forget what side of the car they are on.

If those leak, they drip down onto the h-pipe.
 

General karthief

wonder how much it would cost to ship you a pair
5 Year Member
Aug 25, 2016
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May 30, 2022
#6
  • May 30, 2022
  • #6
Mustang5L5 said:
The aod trans cooler lines also are directly over the exhaust. I forget what side of the car they are on.

If those leak, they drip down onto the h-pipe.
Click to expand...
Passenger side
 
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