1996 Ford Contour w/ 2.4L 6 cylinder, manual transmission, cranks but won't start. Has fuel pressure, does not appear to have spark, coil pack ohms out as OK. Haynes' manual I have indicates I should have battery voltage at center terminal of electrical connector to the coil. I have 4 conductors, not 3 and none have 12 Volts. What do I check next?
It's a 2.5-liter V6, and there should be a 4-wire connector at the coil pack.
With the ignition on, the purple/black wire terminal receives 12 volts from the 20 amp (Ignition DRL) fuse located in engine compartment fuse box. That fuse receives voltage from the Ignition Relay located in the interior fuse panel.
The ignition relay is activated by voltage from the ignition switch. Once activated, the relay sends voltage from the 80 amp main fuse to the Ignition DRL fuse.
Did you get all that? Voltage path: 80 amp main fuse >> Ignition relay >> Ignition DRL fuse >> coil pack. Remember, the ignition must be on when testing.
You said it "does not appear to have spark", but you want to be sure before going any further.
Also, when there is no spark, a good next-step is checking for injector pulse. That's the on/off ground signal coming from the Powertrain Control Module to each injector. No injector pulse would indicate a problem with a main trigger to the whole system -- like the crankshaft sensor or even the PCM itself. Also might want to check if the tachometer (if equipped) is showing a signal while cranking
Injector pulse, but no spark (on any cylinders), would take us to the voltage check described above.
It seems my 99 2.5 contour is having the same issue, I have replace the crankshaft sensor immediately after reading this post couple of weeks ago. Currently, the car is still not firing, that is crank but not start. What should be my next check? Thank you....
If you read the last post thoroughly, you should see that there's more to it than just replacing the crank sensor.
Like I said, a good place to start is confirming a loss of both spark and injector pulse. Missing both directs us to testing the crank sensor, Powertrain Control Module, and all involved circuits.
Pulse, but no spark, would suggest testing the PCM, coil pack and all related circuits there.
If you have a test light and some DC knowledge, give it a shot. But remember that we rarely suggest replacing any parts before accurately diagnosing the failure.
Thanks for the quick response, some of the checks that I did was checking the input voltage to the coil pack which it has 12VDC. The terminal I checked was the one all the way to the right, I believe it is green/black and I got 12VDC as I mention before. I check ohms/resistance between outer pins (on coil pack itself) and it was suppose to be between .5 and .05 but it read .7 on both cars (I have the other car for parts). Also checked ohms between 3 and 4, 6 and 2, and 5 and 1(outlet to sparkplug wires from coilpack) both coil packs reads the same. Tomorrow I will check the pulse to the injectors. Question? What is the proper way to check the pulse to the injector? Obviously I have to disconnected then use some type of measuring device. Since its a pulse signal do you know the amount of voltage should I look for? Thanks......
Last edited by blue32falcon (2/11/2010 1:28 PM)
I had just finish testing for spark and "BAM!!" there's spark, very strong blue white spark. Is this the indication that the PCM is not sending power to the injectors to open up? Theres quarter tank left and no fuel light. When I turn the key to on (not crank) I can hear the pump turn on then off, this whole process takes place within 1.5 second, I assume this is normal. Also there is a check valve I think its for the fuel line right behind the camshaft pulley, when I press on it there was no fuel or fuel being spraying out (no pressure). Was this line suppose to be pressurize all the time? My next step will be taking the intake manifold apart so I can access the injectors for testing. Thanks...
Before you go digging too deep, let's re-start with the basics.
Was spark always present?
Here's are some routine steps when dealing with a no-start condition.
1 -- Get a scan tool and check for diagnostic trouble codes and other relevant data. This often leads you in the right direction. Also be sure the check engine light is coming on with the ignition.
2 -- Check for a good spark. Not just any spark. It has to be strong enough to jump about a half-inch gap (there's a tool for that, also).
3 -- No codes (data looks correct), good spark...gotta check fuel pressure next. When you turn on the ignition the fuel pump will run for about 2 seconds to prime the fuel rail (injectors). You confirmed the pump is functioning electrically when you heard that humming in the tank. But it still may not be putting out enough pressure to run the engine. That's why you need a fuel pressure gauge to test pressure, volume, and fuel contamination. That valve you got the squirt out of is where the gauge hooks up.
4 -- Nothing found up to this point; then I'd check injector pulse, pull a few spark plugs to inspect, and the list goes on. End of the trail being engine mechanical.
Typically you're gonna find something wrong in the first few steps, which directs you to continue testing the system with the symptom, or replace the bad part and finish the job.
Keep me updated.
Sorry took so long but fortunately its fixed, long story short. Like I mentioned before that there was a spark a strong one at that moment I kinda sorta tested if there was any fuel pressure by depressing the valve that is on the fuel line, and there was no squirt nothing at all. On that line I know there should be some type of pressure on it. Last year I was gone overseas and the car was sitting for more than 11 months, upon returning my wife started and notice fuel gauge sitting below empty so she empty 2gallon of mix oil and gasoline in the tank. So she start it and let it run for while until I get back. I didn't get that story not until later. The fix. I change the fuel filter (clogged really bad) and put 5 gallon of good fuel in the tank then I drove it to the gas station top it off after I added fuel condition and fuel system cleaner solution in the tank. Thanks for the help.
Glad you got it going. Fuel pressure was step 3.
haha not to bring back an old thread here, but I am curious. I'm currently working a friends 96 Contour that is cranking but not firing. One of the first steps I took in seeing whether it was getting fuel or not was turning the key and listening for a fuel pump. I can't hear, ANYTHING, and the fuse appears to be good. Can you hear the fuel pump prime on these cars? Or are they quiet?
Thank you! Sorry for bringing up a dead thread once again