I need help figurng out a wiring issue with my 87 mustang lx

Hello i have a 1987 mustang lx hatchback and for some reason my battery is going dead within a couple days of not starting it up. I have pulled the fuse's for the dome lights,radio and hood light, Plus i have pulled the fuse for the door buzzer too and for some reason i still have to jump start the car every 2 days. Could it be possable that it is because the car has sit in a local guy's back yard since 2004 that i am haveing all these issue's with it. The car only has the 2.3 four cylinder in it. Does the 2.3 4 bangers run good and do they get good gas milage or poor gas milage please let me. Was gonna put a v8 in it but plans changed due to haveing two young kids.    

Ps- this is the first mustang i have ever owned so i am trying to learn more about mustangs  
jays_stang

could be an old battery, have had the problem with a few of my cars where the battery has an internal short,, try charging the battery, and disconnet it from car, leave it for a few days and hook the battery back up and see if it will start, if it does not,, bad battery,, if it does,, you have a leakage somewhere in the car,, hook a testlight between the postivive battery cable, and the postive battery cable (in series) and see if it lights, if it does start removing fuses, and see if you can get the light to go out, also disconnect the alternator wires as well too and see what happens, have seen bad alternator diodes cause the same problem.  

I've had similar experiences as Packman. if you have an ammeter, you can put between the neg cable end and the battery terminal anything less an 500 MV draw is usually OK.

As I remember Wayne had a tip here in the forum for a neat battery terminal adapter to make this Ammeter test easier.  

I put a new everstart (neverstart) battery in it from walmart last week and it is draining that battery too when i moved the car today i had to jumpstart it off my truck to just move it

I have also put a new reg. and brush's in the alt. and still haveing the problem

I have also unhooked the battery with the car runninr after jump starting it and the car will stay running without the battery hooked up  
jays_stang

mustangman87:
I put a new everstart (neverstart) battery in it from walmart last week and it is draining that battery too when i moved the car today i had to jumpstart it off my truck to just move it

I have also put a new reg. and brush's in the alt. and still haveing the problem

I have also unhooked the battery with the car runninr after jump starting it and the car will stay running without the battery hooked up

All that proves is your charging system is working but does nothing to isolate a drain. You need to follow my or the Packman's earlier advice if you want to fix this.(or take it to a shop)  

the 2.3 motors get excellent fuel mileage... if everything is perfect.... and its not that hard to *** you might want to ... search out one of the various scan tools to run KOEO and KOER tests...  on the EEC4 system on this car...


NOW....  NEVER ever pull a battery cable off  with the engine running...     for the split second that the cable is first pulled off.. the electrons can build up as they have NO place to go without the battery there to absorb them... this build up is called voltage.. the voltage can spike in that fraction of a second to over 100 volts..    damaging the alternator diodes.. damaging expensive electronics...

use a digital volt meter.. they start at 7 bucks and you generally never need to spend more than 30 bucks on one..

test the battery voltage..  engine off...  headlights on for one minute then turned off...  set meter to 20 volt DC scale..

12.65 is a fully charged battery
12.45 is a 3/4 charged battery
12.25 is a 1/2 charged battery..

if you have over a 3/4 charged battery...  start the engine...  if less ... use a battery charger on 10 amps for an hour..

with the engine running now...   measure the battery voltage... 14.1 to 14.7 volts is expected..

turn on the headlights with the engine running...

measure from the negative battery post to the engine block... 0.04 volts is expected...

measure from the negative battery post to the body...     0.02 volts is expected..

measure from the engine block to the body..................0.02 volts is expected..

post what you find...

now...  this car does not have a lot of modules like later cars do that need to time out...

take your digital volt meter...   shut the car off.. roll the drivers window down..

disconnect the battery  on ONE cable only...    move the test leads into the proper AMP meter holes.. turn the knob to 10 or 15 amp scale..   measure from the disconnected battery cable to the post it was disconnected from

you should get NO MORE THAN 0.015 amps DC....  possibly 0.020...  but thats probably the high limit on that model...

you can do a rough version of this test with a test light..  ENGINE OFF...  disconnect one battery cable..   hook the test light between the removed cable and the post it was removed from..  if the test light on dim.. or bright?????  dim might be OK.. bright is bad...    

at this point..   you can disconnect the meter or the test light.. pull the dome light fuse...   test again...

now with the door open.. you can start pulling the fuses one at a time...   having somebody check the light or the amp meter.. looking for it to drop. ...  be sure to identify which fuse it is...

if you have a harbor freight tools near you .. they have the cheep digital volt meters.. they also have a cheep digital amp meter that plugs into the fuse block when you have a fuse removed..

dome lights.. console lights...    rear foot lights...  rear interior lights.. car stereos are all places that i have had problems with various items staying on...

the above tests will take you probably 10 to 15 minutes to do.. one step at a time following this post that i hope you have printed...

this is exactly how a professional mechanic tests your car...  if he is really searching for your problem...  instead of burning diagnostic time to fill his bosses wallet...  

on 2.3 motors.. i have had problems with egr valves not properly closing and the egr position sensors..

you might also want to change the coolant temp sensor and the air charge temp sensor..  as both of them have been known to get out of spec... and they really effect fuel economy...  

verifying the diverter valve and the TAB and TAD solenoids have proper vacuum supply and are working to switch the thermactor diverter valve..

what is all this stuff .. all these initials..  stuff you will need to learn.. as EEC4 mechanics are few and farther between nowadays...

you will want to join autozone.com.. in the upper right corner of their web site..  log in..   select your car..  there is a repair into section that will have a drivability and emission controls section..  or possibly in the fuel system section...  the individual parts and how they work ...  

Just wanted to say thanks for the tip on the test ordeal i printed it out and on the next nice day we have i will have my buddy help me do the test and i will post what i find from the test and the the results of it too and thanks for the info on the fact that the 2.3 gets excellent gas milage cause i don't want a mustang that i can only look at cause i can't afford to drive it on the road due to the price's of gas  
jays_stang

as for the egr valve could a person take it off and clean it out and also the electric fan on the car right now the guy i got it from hooked a toggle switch up on the car that runs the electric what is it gonna take to fix it the right way on that  
jays_stang

mustangman87:
as for the egr valve could a person take it off and clean it out and also the electric fan on the car right now the guy i got it from hooked a toggle switch up on the car that runs the electric what is it gonna take to fix it the right way on that

Not saying it's impossible but I've never had good luck trying to clean EGR valves. It the seat area is compromised, the car will run like crap.
Typically OEM fans are thermostatically controlled or forced on if the A/C is engaged. You need to find out why the PO bypassed the factory circuits and then correct what's wrong. I don't have an 87 wiring diagram to elaborate further, sorry.  

When i get home on sunday, i can check mitchells wiring diargams, some of the fords had 2 temp. sensors, one was for temp light or guage the other was part of the fan control circuit, but not sure on that year but can check for you  

on the cooling fan issue.... ... one might want to just start out by changing the cooling fan switch

notice pin number 54 on this.. it shows the ECM also has control of the radiator cooling fan...




pin 54 signals the cooling fan controller in the lower left corner of this diagram...



you might as well have the last section of the diagram for the 4 cyl model...



this is what the cooling fan module should look like on your model....



when this type is used.. its normally stashed up under the dash board... i seem to recall that model used the big control box..  but i could be wrong...

it does show this as a cooling fan switch....  so you might want to replace this first...    and make sure you have the proper thermostat installed.. 50/50 mix to 70/30 mix of antifreeze to water..

 

oh... in that style of radiator cooling fan control....  i have had the open frame relay that controls the fan melt and the contacts push back so when the relay cycles on..  the contacts do not touch.. then the cooling fan does not come on...

it looks like both the cooling fan switch and the ECM both have control over the fan controller...

this is the coolant temp sensor...



this is the air charge temp sensor... see the blue device .. its a thermistor... they take a beating.. when its broken.. the computer is half blind and will reduce fuel economy...





with the price of gas...   these two sensors cost just about the same as 3 and a half gallons  EACH at current prices...   swap in new ones.. save a LOT more than that in the first two weeks of driving your car...  

if the connectors that plug into them have frayed wires... you can get new connector pigtails for them also...


this of changing these like changing spark plugs for the computer system..   they might work.. but when worn .. they just don't work as well as they should..  

the actual trick it to properly make sure the cooling fan is under ECM control... verify the proper thermostat is installed...

find somebody with a proper scan tool  get the engine up to operating temps...  run the KOEO and KOER tests...

post the codes.. you will need a ford HC  service manual for your year.. or online info...

if you post the codes some of use have printed manuals ... and can point you in the right direction...

you will personally need a digital volt meter... and probably need to make a set of test leads like this... so you can test the individual circuits without a break out box...

 

that would help cause my dad and i not sure how to read the wiring diagram that the other guy posted we are gonna attempt to try to figure out though  
jays_stang