Mechanics

CRANKS - WONT START

1996 Ford Cougar

Engine Mechanical problem
1996 Ford Cougar V8 Two Wheel Drive Automatic 120000 miles

Had to replace the temp sensor switch for the electrical fan to work to cure overheating issue.

During this process, upon trying to restart car, it wouldnt start.

Checked all standard possibilities, and went finally to giving it a little starting fluid. It fired up with the starting fluid, and ran fine, but upon turning it off, then trying to start it again, cranks, acts like it tries to start, but just dont start.

All vac lines checked, as well as fuel lines, no leaks.
Pulled the fuel check/valve, relieved pressure in system, etc trying to remedy possible vapor lock.
Same result, fires up with a little starting fluid, but not on its own, fuel pressure is good at the lines next to carb.
It is the 4.6, with the throttle body. We have also ran a double check on all fuses, replced a couple of the worn looking vac lines in the engine compartment.

Thank you for your help.
Avatar
Bones1975
April 24, 2010.



Did it start and run prior to the sensor replacement?
Check for codes
Check for injector pulse
Come back with the result

BMRFIXIT
Apr 25, 2010.
Yes - It did start and run prior to sensor replacement, but was overheating, hence the replacement. This not starting issue came up in the process. One suggestion was possible vapor lock, but ran through fuel lines, and have pressure at the supply line that goes around carb area.

There are no codes present, also, we were asked if the check engine light came on with ignition turned on, but not started, but no it does not come on at all, only light on is check gauges, which goes off when you try cranking it.

There is power to the injectors, but not sure how to check the pulse. With the test light, you can hear a click from the injector when you touch one of the two lines, and power of course, as well as the hot line is just power.

New update from my original post, is now today, it wont even start with a little starting fluid, checked plugs to see if there is spark, and there is none, even direct from coil no spark. But the coil is getting power to it.

I will try to get pics of the areas we checked tomorrow when its light out. Too dark at the moment.

Tiny
Bones1975
Apr 25, 2010.
I would not even consider vapor lock, you have a high pressure fuel pump that will push fuel through any vapor that in the system
With key on check engine light should be on if not PCM not powering up and engine will not start
Use a test light and check fuses and constant control relay module
Fuses under hood should be hot at all time #3, #15, #13
Check and make sure relay ground is secured right side upper radiator support

BMRFIXIT
Apr 26, 2010.
CCRM test on the leads 3, 15, 13, all good.
Dont see a ground relay anywhere by upper radiator support, but still looking. All grounds we have found are secure.
I went as far as to test lines into the PCM, according to schematics I found, and it shows good, and that it's getting power.
Still all crank, no fire, and starting fluid still dont help. Think its still not getting spark.
Did test on injectors with ignition on, injector wire pulled. From positive side of battery with test light to fuel injector wire, the solid red wire is hot, but the signal line, green with red strip is not showing anything.

Tiny
Bones1975
Apr 26, 2010.
CCRM is located top by the radiator (black box )
With key on you have power at the injector and the other wire should be pulsed by the PCM
If PCM not powering up will not pulse
With key on should have check engine light on
If fuses OK and ground OK replace CCRM relay and check

BMRFIXIT
Apr 26, 2010.
CCRM is grounded properly, mounted on left side next to radiator, screwed/grounder on frame, and is what I tested with a schemeatic I found online. All output voltages are there, for the appropriate wires. Both what supplies power to ccrm, and which go from ccrm to ecm.
And input lines on ecm show correct voltage into the ecm, from the ccrm.

Tiny
Bones1975
Apr 26, 2010.
If have all powers to the PCM and PCM still not powering up, that will lead me to believe that the PCM is at fault (very uncommon but possible )
If have an access to a scanner run KOEO test
And run check engine light bulb test (use scanner to turn check engine light on and off and check the bulb) if bulb OK and all powers and ground to PCM tested OK
PCM at fault

BMRFIXIT
Apr 29, 2010.