its running like shit

[fiveohhfox]

well i need help bad i did a motor swap with a 90 motor and my car is a 88. 90 is mass air 88 speed density im saying this cuz im still running my speed density harness with the 90 motor but heres the catch im not runnnig no mass air at all no meter or any thing massair so my mustang guy said that was fine i even did a full tune up it still sputters bad and bogs out under 20:smash:00 rpms anything after 2000 rpms is great could it be vacuum or am i over fueling and if i am what would caused this please help

 

[Michael B]

Do you have a vaccuum leak? Is the map sensor ok?

 

[1BIGMOFO]

Why didnt you just keep the mass air? Its a great upgrade over speed density!! Sounds like you have a vaccuum leak to me. Do you hear what sounds like an air leak when you start it?

 

[fiveohhfox]

thats the funny part i dont hear the vacuum leak and it runs better w/o the map sensor unplugged

 

[SBF Coupe]

There is a member on here PrjctLxEnvy, he had his car worked on by a local guy (westchester) and it came out really nice. From what I understand he has a killer notchabck also!Mybe he can give you his number and could help you out.

 

[PrjctLxEnvy]

Yeah you should PM D1coupe thats Pj he is the f'in man and chances are there a vaccum leak weather you hear it or not.

 

[fiveohhfox]

thanx but how would i locate the vacuum leak can i spray carb cleaner thru my throttle body?

 

[lmj001]

soap and water spray the vaccum hoses and intake if the idle goes up you found a leak

 

[fiveohhfox]

ok thanx im gonna try that

 

[BOSS10L]

I agree with the others, it sounds like a vacuum leak is the culprit. That being said, as someone who has owned 3 Foxes (2 SD, 1 MA), I would definitely recommend switching over to MA. You have the parts, why not? If I had an SD Fox at this point, I'd either make the MA conversion or just go straight carbed. Good luck!

 

[lmj001]

sd runs fine with stock engine if you have a lot of mods i would go with the maf conversion if not you will not get much improvment over what you have switch to maf wont do a thing if you dont get the other problem fixed first save your money for the thing to get it running right then do the maf switch

 

[fiveohhfox]

sound greaaaaaaaaaaaat

 

[dsblk93gt]

sd runs fine with stock engine if you have a lot of mods i would go with the maf conversion if not you will not get much improvment over what you have switch to maf wont do a thing if you dont get the other problem fixed first save your money for the thing to get it running right then do the maf switch

Exactly....

I've had 12-14 5.0's , 3 of which were 88's and they were the fastest. MAF is pointless until you get into heads/cam/etc.

 

[dsblk93gt]

Did you re-use all the sensors off your original motor or leave the ones from the 90 engine? Have you checked the fuel pressure at idle?

 

[fiveohhfox]

i bought the 88 as a shell with the harness in and just dropped my 90 motor in it how do i check the fuel pressure?