1987 Ford Mustang help

FOXMUSTANG2

MEMBER
1987 FORD MUSTANG

Engine Mechanical problem
1987 Ford Mustang V8 Two Wheel Drive Manual 27000? Miles

i have an 87 mustang gt high output or ho. I had the engine out replaced oil pan, upper and loer inakes with cobra ones, got a 70 mm throttle body, headers new distributo cap and rotor, did not remove distributor. After I put engine back in and started it it fired right up but idles rough and I can smell gas in the oil. It also spits out oil or gas from the tailpipes making black smoke. I also had removed all egr, emissions such as smog pump. The ac is gone as well. Before I took the engine out it ran fine, wat could be causing this problem. I never touched the engine internals wen it was out.

5 Replies

JACOBANDNICKOLAS

MECHANIC
109,885 POSTS

Did you update all fuel management equipment and controls? 1987 GT was the last year for SPEED DENSITY and modifications are not possible without the addition of a mass air flow sensor. Thus, you need to update the computer to an aftermarket or a newer model year. NOTE: The black smoke is because it is running too rich (too much fuel).

Let me know if you have any questions.

Joe

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Wednesday, January 20th, 2010 AT 8:49 PM

FOXMUSTANG2

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The car didnt have the mass air flow, I didnt do anythin to the computer, do u think with these mods would make the computer let to much fuel into the system and should I add a mass air flow and wat would that involve with the compuer, just finding one off say a 93 or one with mass air flow and plug that in, how involved is it, also could it be piston rings or somthing internal? Thanks

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Thursday, January 21st, 2010 AT 9:29 AM

JACOBANDNICKOLAS

MECHANIC
109,885 POSTS

Your car didn't come with a mass air flow sensor, but the parts you installed requires one. That is why it is running so rich. THis will require an update of computer, the addition of a MAF sensor. Actually, I can't even say the car will run correctly with that. But I can say, it's running rich because of the modifications you made. As far as jjust replacing the computer and adding the maf, it may require the changing of other sensor too. The problem is you took the last year of a speed density system and only changed some of the parts. Now the computer doesn't know what to do.

As far as internal damage, I don't think that is a concern, but I will say if it is running that rich, it will eventually thin out the oil.

Joe

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Thursday, January 21st, 2010 AT 9:05 PM

FOXMUSTANG2

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Ok thanks for your help I agree with the mass airflow mod u talk about and dont think its an internal problem either since it wasnt running rich or blowing smoke before these mods were made, my question now is what you would recommend doing to change to a mass air flow, do I need all new wiring harness, and things like that and how exspensive can that get. Thanks for your input

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Thursday, January 21st, 2010 AT 10:06 PM

JACOBANDNICKOLAS

MECHANIC
109,885 POSTS

Honestly, my recommendation is to change things back the way they were. I'm sure that isn't what you want to hear, but that is the bottom line. By the time you get sensors to work, the right computer, change wiring, vacuum. God knows what kind of expense you'll get into, headachs you'll have, and how long it will take.

I wish I had a better answer for you. If the car was one year newer, this wouldn't be a problem.

Let me know if you have other questions.

Joe