94 ex acting crazy

[bansheeman1]

my 94 ex is acting crazy
it will allways crank, it may or may not start
holding it to the floor seems to help
when it starts it revs to 3000
then after a wile it goes down to 2000
if you turn on the a/c the check engine light turns on.
Some times it will die and not start back up
I put it on the scanner, no codes
when i unplug the scanner from the battery it changed the rpm
I also cleaned the throttle body and idle air valve

 

[MrShorty]

First thought is vacuum leak(s).

 

[bansheeman1]

I changed the tps and the idle air motor
it idled fine till it died when i started it back up 2500 rpm
also installed new plugs
:roll:

 

[slag]

do you hear a loud hissing from the engine compartment?

Check your vacuum tree on the upper intake manifold for cracked hoses or missing vacuum plugs.

Check also your vacuum connection at the FPR (fuel pressure regulator). Sometimes they get weak and fall off.

 

[Positive Vibes]

do you hear a loud hissing from the engine compartment?

Check your vacuum tree on the upper intake manifold for cracked hoses or missing vacuum plugs.

Check also your vacuum connection at the FPR (fuel pressure regulator). Sometimes they get weak and fall off.

Thats what I would say and have you cleaned the MAF?

 

[bansheeman1]

I cleaned the Maf
the fule pressure is at 38 and holding
I seems to idle fine with out the idle air motor hooked up(but then it dyes when the a/c is on)
also when the a/c is on the check engine light comes on even with it unlluged

also it still dies at random and will not start for a wile

 

[Positive Vibes]

Did you change the FPR or the PCV? Those are fairly cheap and easy to change.

 

[bansheeman1]

fule pressure is ok 38 and holding and is not gassey
the idle is changing by the computor not vaccume

so i did not change the fpr or the pvc

but if it will will help i have them off a spare intake

any way i gave up today and took it to a shop

 

[Positive Vibes]

Let us know what the shop says.

 

[bansheeman1]

shop says the computor is bad

I hope this shop just dosent start changing parts

computor for a 5 speed is hard to find

dealer only?

well i found one for 75. at a junk yard

after calling 9 yards

5 parts houses

and the dealer

we shall see if that is all it needs

thay sayed there ford scanner did not even talk to it at all

my matco scanner worked ok on it

 

[Positive Vibes]

Sounds kinds fishy. Usually when a computer fails or electronics, they usually aren't intermintent unless its a connection or something. If a computer is "bad" than its not going to function at all. Which means the car wouldn't run, at least would wouldn't think so. Hopefully thats your problem cause $75 isn't bad. Keep us posted please.

 

[bansheeman1]

the shop just called and it is running good
so we shall see yea

 

[bansheeman1]

well it runs great

the check engin light came back on the PFE is bad
what ever that is
but it still runs great

 

[Positive Vibes]

So the changing the ECU didn't fully cure your problems?