Fox T-Bird/Cougar Forums

Technical => Engine Tech => Topic started by: black magic on March 10, 2018, 11:46:02 AM

Title: 1983 5.0 throttle body engine stalling issues, any ideas?
Post by: black magic on March 10, 2018, 11:46:02 AM
Hello guys,

Its been quite some time since I posted, since then I've added to the fleet with a 83 Cougar LS 5.0. Its up too 132,000 miles but really well cared for, single owner had it until I bought it in 2011.
Its completely stock with the 5.0 throttle body setup,not my preference for sure.

-Recently I've had problems with the engine dying for no apparent reason. It's happened at speeds of 65mph on the freeway and mostly 20-40mph when on city streets. It wont restart right away either. Typically I coast off to the side and it takes 5-10 minutes for it to start again. Ill try cranking it over 4 or 5 separate times and it if it doesn't work I let it sit a few minutes and try again. Needless to say, its a scary situation when it happen in a large city like I live in. I'm needing to use the car as my DD for a while since my other vehicle was totaled in an accident(drunk driver).
Once it does restart it seems to run normal. My drive is only 12 miles one way too and from work so its not like the car is being run long hours before this happens.
Any ideas would be greatly appreciated.

thanks
Dennis
Title: 1983 5.0 throttle body engine stalling issues, any ideas?
Post by: kylesburrell on March 10, 2018, 12:49:54 PM
I had a similar issue where my car would die like that. Let It sit, states and runs just fine. My issue was with my TFI module, or ignition control module. It has a couple names. But it's the thing mounted under and on the side of your distributor. Most of them fail because of being subjected to heat.
Title: 1983 5.0 throttle body engine stalling issues, any ideas?
Post by: Haystack on March 10, 2018, 02:36:12 PM
Weren't 83's a duraspark system? Or did they already have a tfi?
Title: 1983 5.0 throttle body engine stalling issues, any ideas?
Post by: kylesburrell on March 10, 2018, 02:47:29 PM
Ooops, think you're right haystack.
Title: 1983 5.0 throttle body engine stalling issues, any ideas?
Post by: black magic on March 10, 2018, 06:22:07 PM
Quote from: kylesburrell;464908
Ooops, think you're right haystack.

Yeah thats 1984 and newer from what I understand. I had read about that when googling the issue a while back.

Could it be the fuel pump going bad?
Title: 1983 5.0 throttle body engine stalling issues, any ideas?
Post by: Haystack on March 10, 2018, 09:53:03 PM
Buy a cheap harbor freight fuel pressure tester. Take the rubber hose straight to the gauge and hook it to the outlet of the fuel filter. If its not around 40 psi, of start looking at fuel.
Title: 1983 5.0 throttle body engine stalling issues, any ideas?
Post by: jcassity on March 11, 2018, 10:01:49 AM
random things........ cause i have a lot of experience with all the various CFI's,,, but very little on durasparkII although i do i have some prints about it.

i am going to go out on a limb and think "when stuff gets warm, stuff starts to fail".... so in random here goes............

with a bone cold motor ,,
-remove air cleaner
-look down into the CFI
-observe the position of the throttle plates (they should be nearly closed due to last time running.
-manually move the gas pedal lever and allow it to come back to a resting position........
-the throttle plates should be "more open" now than before.. ... this verifies that the automatic choke is set somewhat correctly(located on pass side)
-if not, loose the three side mount screws and rotate the black plastic housing to just "barely" open the throttle plates. 
lock down the holding screws.
-run car in driveway with some small weight on the gas pedal to make it run at around 1000rpm for about 15min
-if it dies ....... scroll down
-if it does not die then remove the small weight
-if it dies........ scroll down
-if it does not die, scroll down

random things to check...........
-turn car off and listen to the sounds from the coolant fill tank and radiator or hoses.
-verify at night or a dark situation that your spark is "Blueish white",, orange is bad.
-you might  be one of the few with a pump in the fuel tank and a pump on the bottom of the cars frame (two pumps)... if yes.....
then pm or get softtouch (member) on this thread because he has this particular design memorized!
-after car is hot, on the CFI driver side there is a vac actuated idle plunger.. with the car at idle, is the plunger touching / pushing the lever?
-if yes then move on....
-if no then this item came "before" the idle control motor assy and after engine/auto choke pull off is rather hot, your throttle plates should be returning to a position that is allowing the plates to stay slightly open.


-your cfi system has a test port on top of the fuel rail on the driver side with your blue top injectors.
with warm motor test fuel pres there and look for 40lbs at idle.
-shop manual says to add extender hose to duct tape guage to windshield, with tester hooked up observe the fuel presure in between shifts.  The psi can not go below 25psi or else the pump or (pumps) are on thier way out. 

I believe your EECIII system has a crank position sensor,,,
If you have a module mounted to your distributor with a six wire connector then you are not Duraspark/EECIII.... post back what your system is.

check rock auto to price out a voltage regulator / ignition module,,,, i believe yours is mounted on the pass side strut tower... this item does go bad and from the mileage you say, its likely due.

important.......
on the rear of the cfi driver side there is a main vac port (tiny gold 2'' long fitting).
you lift the CFI off the engine, and flip the CFI over.. ... under the CFI chip away at all the carbon deposits that dont below!!!!


FYI,,
your fuel presure regulator on top of the CFI from the factory is adjustable.,,, unless its been replaced with AFTER MARKET.
if there is a freeze plug on the top center, then simply use a tiny drill bit then a self tapper screw and pop out that freeze plug to reveal an allen wrench adjustment.
If your FPR has a plastic plug, then its been replaced,,,, and you can also assume the CFI has been removed.

there are a lot of mechanical gizmos and gadgets around the EECIII CFI system (as a part of the CFI) and all those linkages and such that track and follow your gas pedal and or follow a "warmed up engine" and provide a job need looked at.


my gut feeling is telling me that its either your ignition module or cam sensor and after engine is warm, something is intermittent.

i cant remember if the EEC III system had actual points down in the distributor or not... but if thats bad, usually you would have troubles without a hot motor.


call if you want.... scott 304 772 3411

sorry so random.
Title: 1983 5.0 throttle body engine stalling issues, any ideas?
Post by: jcassity on March 11, 2018, 10:03:45 AM
Quote from: Haystack;464918
Buy a cheap harbor freight fuel pressure tester. Take the rubber hose straight to the gauge and hook it to the outlet of the fuel filter. If its not around 40 psi, of start looking at fuel.

there's a shrader valve on top of the CFI driver side.

also,, to get rid of that "hesitation off the line, remove injectors and start a sheet metal screw into the top of the injector,,, pull with pliers to remove and dispose of the injector screens.
Title: 1983 5.0 throttle body engine stalling issues, any ideas?
Post by: black magic on March 11, 2018, 05:11:04 PM
Quote from: jcassity;464920
there's a shrader valve on top of the CFI driver side.

also,, to get rid of that "hesitation off the line, remove injectors and start a sheet metal screw into the top of the injector,,, pull with pliers to remove and dispose of the injector screens.



Scott,
Thanks for all the suggestions. Ive tried to cross a few things off from your list. I'm not very mechanically inclined unfortunately. I can handle some basics but this may be over my head with how many different scenarios there are.
 Below are a few pictures I took. From what I understand its the Duraspark setup, no module.
On the last picture I posted, is that Yellow cap the shrader valve you are referring too earlier to test the fuel pressure?


X
X
X
Title: 1983 5.0 throttle body engine stalling issues, any ideas?
Post by: black magic on March 11, 2018, 05:17:24 PM
-When I took off the air filter and manually moved the gas line the throttle plates went back to the same position as when I started which seems to be all the way closed.

-I didnt have any luck with the car shutting off when it sat and idled at around 1000rpm for 15 min.
-I can hear the fuel pump humming in the tank when the key is turned on, it does then turn off like normal a few seconds later.

-The water pump, belts and hoses were all replaced a year ago, since then the car has only been driven about 1,000 miles.
Title: 1983 5.0 throttle body engine stalling issues, any ideas?
Post by: jcassity on March 11, 2018, 10:31:21 PM
yup, thats the fuel pres test port,, the regulator is the round gold thing,, and apparently it has been replaced sometime in the past,, unless you see an allen head screw down in that hole.

so,,, you know whats coming to mind now.................
something that seems to always be the problem when everything else seems right??

Ignition switch.,,,,

its not easy to install if your a tad lean on wrenching so get a trusted friend to change it out.

its really worth shot gunning a part this cheap to see "if" it fixes the issue.

something is over heading within your 11mile trip to work... again i am speculating something is over heating based on what you said.............


oh,, heck,, by the way.........

do you have a smog pump down on the lower left of your motor.?

remove belt, grab the smog pump pully and spin it,, if its binding up,, that could be adding some load on the engine,, so that when you are driving along and you happen to let off the gas coasting down hill or something, the extra load will litterally slow down the rpm enough to shut off the car.

this "feel" test i mention is only best done when the engine is hot unfortunatly.

once upon a time i threw a belt a couple times because of the smog pump pully locking up.

you can short belt the engine by removing the smog pump,, and the plastic impellar on the face,, then route a shorter belt on, the belt will barely clear the metal case of the smog and you can just leave the smog pump on the car.
Title: 1983 5.0 throttle body engine stalling issues, any ideas?
Post by: jcassity on March 11, 2018, 10:33:54 PM
i made a termometer out of that automatic choke pull off ,, see the thread in the lounge about a couple weeks ago.
Title: 1983 5.0 throttle body engine stalling issues, any ideas?
Post by: jcassity on March 11, 2018, 10:35:36 PM
by the way,, you should have a small "ish" magic little box somewhere that is called the ignition module.  its shown in a haynes manual for EECIII systems.
Title: 1983 5.0 throttle body engine stalling issues, any ideas?
Post by: CoogarXR on March 12, 2018, 08:39:28 AM
When I had my 83 5.0 that would die randomly, it was a cracked wire on the crank sensor. If I recall, there is a harness the runs down the front of the engine. If you jiggle that while it's running, and it stalls, that's your issue.
Title: 1983 5.0 throttle body engine stalling issues, any ideas?
Post by: mcb82gt on March 13, 2018, 04:30:00 PM
Those cars have a odd sensor.  By brothers went bad and wouldn't start again ever.  Crank sensor may be correct, or the wiring to it.  Iginition module, or its wiring is another good culprit.  I would suspect if it was a binding smog pump, the engine should restart easily.
Title: 1983 5.0 throttle body engine stalling issues, any ideas?
Post by: black magic on March 18, 2018, 11:44:38 AM
Hello guys,

Thanks for all the help. Ive borrowed the in-laws spare vehicle this past week and been getting by with it as we planned what to do with he Cougar.
I bought a MSD ignition and have a mechanically inclined friend that's going to help me install that in the next few days. We figured it's the most likely cause of all this and if not at least it will help the car  going forward.
Ill post some updates as I have them.

-Dennis