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3.8 CFI no start

i've got an 87 t-bird w/3.8CFI.  All of a sudden it just will not start.  I have spark and timing and i just replaced the fuel pump. i am getting 40PSI at the fuel test port on the CFI.  I cleaned the tank(the fuel was reddish from the rust) and replaced the fuel(lots of debris) and then i blew out the fuel lines up to the CFI and of course replaced the filter.   
i think its a fuel problem because of all the debris in the tank so here is my questions...how do i tell if the injectors are squirting fuel on a CFI?  I manually pulled the throttle back several times but no fuel.  I know the computer controls the injectors but should it spray fuel still when i manipulate the throttle(w/key on)?  I am going to pull the CFI off so where should i look for blockages and what parts of the CFI should i look at for possible blockages and cleaning?  thanks for the help....:D

3.8 CFI no start

Reply #1 –
1-
form a paper towel looped under each injector
2-
crank engine
3-
check paper

if no fuel,, let us know

If you do have fuel let us know

I would highly suggest you either :
A- delete the injector screens
B- remove and replace them.


what color is the spark
what is the fuel presure reading after you are done cranking 1min, 5min and 10min later leaving the key on.

also, while you are cranking , you should be able to see the fuel spurting with the light.  If you cant smell it, its probably not pulsing.

Also, with a test light you will be able to back probe either injector.  While cranking, the test light should blink. THis is called the noid light test.  What this means is the computer has a good hull effect / stator signal and the injectors are being told to come on and go off.
what it does not tell you is "if" the injectors are actually opening and closing due to build up of .

There is a square head bolt fitting in the rear of the cfi that can be removed.  This is an secondary point of fuel presure reading that can be fabricated up as a secondary pump reading such as in your dash.  If removed and the key turned on, it will allow you to flush out the top side of the injector rail of the CFI (horizontal area with the shrader valve to the drivers side). 
First, place a white paper towel along the back of the cfi just uner where the square head screw is. 
Remove the square head screw.
turn on key till pump runs then shuts off.
turn off key, wait till you hear a click.
turn on key till pump runs then shuts off.
turn off key
now go check the paper towel for debris.
install plug back in hole.


Next...
remove shrader valve and repeat the above process but placing a paper towel under the shrader valve area.


if you see debris of any kind, its time to separate the cfi and do some injector work.

for that detailed info, see my diy link.

see below pic of the cfi injector screen.  its attached to a screw that i used to barely start into the top of the injector and give a good hard yank out.  the rim of the screens are usually brass which aids in removal using screw that you  find starts to grab snuggly.

My old 3.8 had no injector screens for severa years and no issues.  I finally figured out the remedy to that age old "hesitation" issue got solved upon removal.

A couple things about the CFI that you might find handy.
1- the stock fuel presure regulator is adjustable.  If you still have a freeze plug dead center top of the FPR,, drill a little hole in it then get in there with a nail or something and pop it out.  Once in there you will see an allen screw.  see my diy link to associcate how much psi is gained/lost for each full turn cw/ccw.

2-if you feel down in your upper half of the cfi, you will notice there is a significant air reduction as soon as your finger makes its way into the lower half but just above the butterflies.
take the CFI apart, remove the butterflies and throttle linkage.  Hone out the lower half of the CFI until it basically matches diameter with the butterflies.  Im not sure why ford restricted this area but its there even on the larger bore CFI for the 5.0 engine that had CFI.

3.8 CFI no start

Reply #2 –
see below example of the 5.0 CFI lower half where the housing basically gets restricted just near but above the trottle plates.

BTW, the 5.0CFI is a direct swap to your 3.8 but you must not use the blue top injectors.  they deliver wayyyyyyyyyyy too much fuel for your 3.8 to consume plus the impedence of the blue tops to not agree with what your 3.8 eec needs to see. 

however,,,,,,,,,,,,,,,,,,, and this is just from my personal experience,,,,,,you can stuff in a 5.0 eec from a cfi car into your 3.8 car and then you can use your 5.0 cfi with blue tops.  just be prepared for rich running conditions but the car will run fine.  just turn down the fuel presure a little.

in both cases, the restriction on all CFI units is in the lower half as pictured.

3.8 CFI no start

Reply #3 –
woohoo..i cleaned/removed the injector screens(eeek) and it fires at the first flick of the switch. now the bad,,,,it's got a bad knock somewhere....i think it's top end like a lifter. the cars previous owner neglected her in the worst way. i am trying to resussitate(SP?) this thing(only paid $200) but with the price of s metal......:beatyoass:

3.8 CFI no start

Reply #4 –
and,,,,,,,,, you had no problem with the phillups screws?

if not ,, you da man!!

3.8 CFI no start

Reply #5 –
Dump a qt of transmission fluid in your oil and let it idle for a litte while.  Do an oil change and use thicker stuff.

that will cure the little top end noise for now.

3.8 CFI no start

Reply #6 –
What kind of oil is he using? If it is synthetic oil then I wouldn't mix ATF with it.

3.8 CFI no start

Reply #7 –
it sat for nearly a year so i am hoping it's a sticky lifter. i did an oil change...i had to dynamite the oil filter off...and i put generic 10W-40 in it with a quart of engine cleaner. i'll do the trans fluid trick tonight...or will the marvel mystery oil or another equivalent work?

3.8 CFI no start

Reply #8 –
it really doesnt matter, trans fluid or oil,, just do a couple of unscheduled oil changes in the next couple of months or weeks depending on how much you drive.

engine cleaner is pretty agressive and will loosen things up which,,,,,MUST Fall down the tiny little hole on the lower left and right side of each head (oil return ports)

If these ports become clogged or chocked off, oil will not return quickly enough to the pan.

To check, (3.8 is easy) , remove valve covers
run a dowel or wire down into the hole on the lower left and right and sort of clean that part out as though you were cleaning a gun barrel.

while you are in there , s up any goop collected up around the lower side of the heads and along the valve springs ect.  I found using a shop vac with a home made reducer taking the size down to 1/4'' works great to suck the grime and goop out on those motors people love to dump "marvel" or stp oil treatment in.

To clean out the oil return ports, use a copper tube or some other tube you can fab up to the shop vac.  start sucking the oil return port out from top going down.

3.8 CFI no start

Reply #9 –
well........i pulled the passenger side cover off and discovered a bent pushrod. . it's the second one from the rear of the motor(intake?).
i'll need to pull the head to get it out but question is...is that a terminal problem or can i put a new set of pushrods in it and call it good?  will a thing like that jack the cam lobe up? i found it right away due to the slop and when i followed the rod down there it was...nice 's' shape.  it's only a $200 beater and it sure runs smooth, but if this requires a full engine rebuild i'm gonna pull that rod out and drive it to the spers.:beatyoass: :beatyoass:

3.8 CFI no start

Reply #10 –
the lifters slide up and down in the block just below the intake.  that one may be kinda stuck enough to where it refuses to go all the way down.

Its really not that bad of a job to remove cfi / intake and replace the lifters. If you wanna go cheap, pushrod set from a bone yard doner will do but lifters are not so easy of a call to make.

I would replace all the lifters.

Compare your effected rocker arm to another that was not effected and look for wear.

Remove rocker
the center part is a fulcrum where the bolt passes
there are two lines on the bottom of the fulcrum
if the lines are worn off , its got some serious wear.
Those lines help transfer oil and gives a visual of wear.


Its a sin not to replace all lifters while the intake is off.  I could deal with used push rods, just dont replace 1 lifter.  You already admitted it was a very inexpensive car to purchase.  Compare what a new car payment would be a month for you and your situation and spend 1/5 of that a month on parts a little at a time and you find out you made out in the long run.

3.8 CFI no start

Reply #11 –
thanks jcassity, i got 2 weeks of vacation starting monday so i'll pull the topend off and have a look.  i knew about not replacing 1 lifter and besides, you cant just buy 1!  i bought it as a fixer-upper then found a turbo coupe for 500 so the t/c took over as primary project.  i was trying to get it running decently so i could sell it and make some money to put towards the T/C.  I dont want to puppies off a lemon though, but then again i dont want to put a grand in a $800 hooptie....my biggest concern is it gouged the cam but i'll update this next week, maybe take some pics of the process of removing the top end.

3.8 CFI no start

Reply #12 –
all right...i got it fixed. FYI autozone sells individual pushrods($1.50) so i decided to replace the one rod.  I didnt feel like pulling the head so I dremel tooled the bent rod in two and replace it with the new one.  I rotated the motor slowly to make sure there was no binding(none) so i cleaned up the lifter galley good and put it all back together and it  runs like a champ.  I am impressed(so far) as the lil'  6 cyl seems to have lots of power.  It's stuck on fast idle and wont kick down so i'll recheck my vacuum lines. i had to make my own gasket for the CFI as nobody stocks them, but the job went fast. 
  As a side note, what the  F$^*ing hell is with fuel pumps on these cars...i bought a real Walbro 230( of whatever the F it is) for my TC and it died the day i fixed this car.:punchballs: :punchballs: :punchballs: :punchballs: :punchballs: :punchballs:  no fuel pressure at the check point. i'm gonna rerun the wiring check again but  it if its a bad pump this time i'm wiring up an external pump.
 

3.8 CFI no start

Reply #13 –
The do to make a cfi base plate kit, not sure where you are shopping at.

The fast idle will be the idle tracking switch in the IAC motor.  Loosen the lock down screw a little.,, the rotate the horizontal adjstment bolt until it backs down the trottle linkage.

Does the pluger shoot out when the key is truned on?  if so,, fiddle with the ajustment and it should back off.

If the plunger does not extend or you dont hear a buzzzzzz when you turn key key on, its probably defective in some way or a wiring issue to the 4 pin connector.