Home
About Us
Calendar
Fiero Documents
Merchandise
Tips
Links
Members
Message Board
Other Fiero Clubs
VIN Decoder
Speed Calculator
GFC Facebook Page
 
« previous next »
Pages: [1]

Author Topic: Backfiring  (Read 14398 times)

0 Members and 1 Guest are viewing this topic.

Plastic Fantastic

  • Newbie
  • *
  • Posts: 7
    • View Profile
Backfiring
« on: March 27, 2020, 11:51:25 pm »
Help.. I have a 85 GT , on any given day I can hop in , cranks right up and runs great for 45-- 60 minutes. Stop at a store , come back attempt to start but it doesn't want to. When I do get it started it runs bad for half a mile , backfires and dies. You can smell the in burnt gas. Any ideas? I can replace parts but not good with diagnostics. Thanks.
Logged

GTRS Fiero

  • Hero Member
  • *****
  • Posts: 12,510
  • It is what it is.
    • View Profile
Re: Backfiring
« Reply #1 on: March 27, 2020, 11:53:56 pm »
Have you checked the ICM?
Logged

Plastic Fantastic

  • Newbie
  • *
  • Posts: 7
    • View Profile
Re: Backfiring
« Reply #2 on: March 28, 2020, 12:46:49 am »
Not yet I read a post earlier that referenced the ICM and that prompted me to post. I will Google the location in engine bay and how to test it.
Logged

TopNotch

  • The Duke of URL
  • Global Moderator
  • *****
  • Posts: 3,984
    • View Profile
Re: Backfiring
« Reply #3 on: March 28, 2020, 09:10:22 am »
The ICM is in the distributor. The best way to test it is to take it to a parts store with a tester.
But before you do all that, you should check your trouble codes. There might be a clue about your problem. See this page for info on how to check them. Note: your ALDL connector may be upside down from what is shown on that page.
Logged
The more complex the mind, the greater the need for the simplicity of play.

Fierofool

  • Global Moderator
  • *****
  • Posts: 10,745
    • View Profile
    • Georgia Fiero Club
Re: Backfiring
« Reply #4 on: March 28, 2020, 09:13:49 am »
It's the black plastic electronic component inside the distributor.  When replacing it, one should discard the clear thermal grease that comes with it and use a white or silver thermal grease that can be purchased in small tubes at some auto parts stores or computer and electronics stores.  Smear a coating of it on the metal plate on the bottom of the ICM and install it. 

Raw gas smell could also be caused by the Coolant Temperature Sensor located on the end of the engine just above the water pump.  It tells the computer how it needs to adjust the air/fuel mixture.  If it fails it can cause the mixture to be very rich. 
Logged
There are three kinds of men:

1.    The ones that learn by reading.
2.    The few who learn by observation.
3.    The rest of them have to pee on the electric fence and find out for themselves.    Will Rogers

Plastic Fantastic

  • Newbie
  • *
  • Posts: 7
    • View Profile
Re: Backfiring
« Reply #5 on: March 28, 2020, 11:18:14 am »
Thanks everyone for the information. Plan on checking it all out and will report back.
Logged

Plastic Fantastic

  • Newbie
  • *
  • Posts: 7
    • View Profile
Re: Backfiring
« Reply #6 on: May 10, 2020, 09:32:08 am »
Update. Went straight to the coolant temperature sensor reached in to remove the connector and it just fell off , the connector housing on the sensor was broken , I just plugged the connector straight to the sensor , fired it up and drove 45 miles , stopped four times , cranked right up with no gas smell. Haven't got to replacing the sensor yet , but I will. Thanks to all in the Fiero community.
Logged

GTRS Fiero

  • Hero Member
  • *****
  • Posts: 12,510
  • It is what it is.
    • View Profile
Re: Backfiring
« Reply #7 on: May 10, 2020, 09:36:00 am »
Glad it's working.
Logged

Roger

  • Paid Members
  • *****
  • Posts: 850
  • If it’s the thought that counts, think money.
    • View Profile
Re: Backfiring
« Reply #8 on: May 10, 2020, 02:08:00 pm »
I guess you mean the sensor beneath the fill neck?
Logged
You can't fix stupid but, you can adjust it with a 2x4.

Plastic Fantastic

  • Newbie
  • *
  • Posts: 7
    • View Profile
Re: Backfiring
« Reply #9 on: May 11, 2020, 06:26:06 am »
Yes. At the fill neck.
Logged

Fierofool

  • Global Moderator
  • *****
  • Posts: 10,745
    • View Profile
    • Georgia Fiero Club
Re: Backfiring
« Reply #10 on: May 11, 2020, 08:41:54 am »
PlasticFantastic, you may have told me before and if you did, I don't remember.  Where are you located? 
Logged
There are three kinds of men:

1.    The ones that learn by reading.
2.    The few who learn by observation.
3.    The rest of them have to pee on the electric fence and find out for themselves.    Will Rogers
Pages: [1]
« previous next »