no spark, no injector pulse
#1
12-09-2011, 08:22 AM
no spark, no injector pulse
2002 Protege 2.0ltr FS engine, auto trans
I have a no start due to no spark and no injector pulse.
Previous owner couldn't fix so now I have the car, they said it quit and they were told it needed a crank sensor. They replaced it and it ran for a day then quit again. Then they were told it needed a cam sensor, after changing it with no luck they gave up on the car.
My first step was to scan for codes with a MT2500 scan tool, nothing showed up. Looking at the data streams nothing appeared off. Spinning over showed an RPM reading between 150 and 175 so I assume the crank sensor is working. I checked the air gap and voltage with a DVOM and they show OK.
I checked the cam sensor resistance and found it to be way off so I reinstalled the original as it ohmed out in specification.
The car fired right up and ran perfect. I shut it off after a couple minutes and then it went right back to the same no spark, no injector pulse, still no codes.
Checked the ECM power and ground wires and they showed to be OK. Removed the ECM and opened it up, no signs of damage. Ordered a rebuilt ECM anyway and installed it and the car fired right up and ran fine the whole day. I shut it off and restarted several times that day with no problems.
while it was running I watched the data and it took a long time for closed loop operation, over 30 minutes. The upstream o2 sensor heater constantly cycled on and off and the sensor showed lean (0.08v) until it finally went into closed loop. The down stream stayed at 0.00 the whole time and the heater stayed on too. I contribute some of this to a cracked exhaust manifold.
I drove the car down the road and it ran fine, no hesitation or misfire. However when the transmission shifted into OD it quit pulling and the OD indicator started flashing. I turned the key off and restarted the car, the light was no longer flashing so I took off and it did it again, this time i just drove the car in drive with no problems. When i got back I checked for codes and it showed something about a transmission range sensor. At this point I called it a day.
The next day the car is right back to no spark and no injector pulse, WTF?
Here is where it gets kind of odd. On the first key cycle from off to start the injectors will pulse one time when it first starts to spin over, they will not pulse again if you just let up to run and try to start again but after you let up again the spark plugs will fire one time about half a second after the engine stops turning. The plugs will fire once every time the ignition is released from start after that as long as you don't turn the ignition to off but the injector will never pulse again until the ignition is turned all the way off and back on. The injector pulse and spark never happen on the same key cycle.
I don't know if the transmission problem is related or not, the previous owner never mentioned it. It just seems odd that any time one part was changed it ran for a short time. Any suggestions?
I have a no start due to no spark and no injector pulse.
Previous owner couldn't fix so now I have the car, they said it quit and they were told it needed a crank sensor. They replaced it and it ran for a day then quit again. Then they were told it needed a cam sensor, after changing it with no luck they gave up on the car.
My first step was to scan for codes with a MT2500 scan tool, nothing showed up. Looking at the data streams nothing appeared off. Spinning over showed an RPM reading between 150 and 175 so I assume the crank sensor is working. I checked the air gap and voltage with a DVOM and they show OK.
I checked the cam sensor resistance and found it to be way off so I reinstalled the original as it ohmed out in specification.
The car fired right up and ran perfect. I shut it off after a couple minutes and then it went right back to the same no spark, no injector pulse, still no codes.
Checked the ECM power and ground wires and they showed to be OK. Removed the ECM and opened it up, no signs of damage. Ordered a rebuilt ECM anyway and installed it and the car fired right up and ran fine the whole day. I shut it off and restarted several times that day with no problems.
while it was running I watched the data and it took a long time for closed loop operation, over 30 minutes. The upstream o2 sensor heater constantly cycled on and off and the sensor showed lean (0.08v) until it finally went into closed loop. The down stream stayed at 0.00 the whole time and the heater stayed on too. I contribute some of this to a cracked exhaust manifold.
I drove the car down the road and it ran fine, no hesitation or misfire. However when the transmission shifted into OD it quit pulling and the OD indicator started flashing. I turned the key off and restarted the car, the light was no longer flashing so I took off and it did it again, this time i just drove the car in drive with no problems. When i got back I checked for codes and it showed something about a transmission range sensor. At this point I called it a day.
The next day the car is right back to no spark and no injector pulse, WTF?
Here is where it gets kind of odd. On the first key cycle from off to start the injectors will pulse one time when it first starts to spin over, they will not pulse again if you just let up to run and try to start again but after you let up again the spark plugs will fire one time about half a second after the engine stops turning. The plugs will fire once every time the ignition is released from start after that as long as you don't turn the ignition to off but the injector will never pulse again until the ignition is turned all the way off and back on. The injector pulse and spark never happen on the same key cycle.
I don't know if the transmission problem is related or not, the previous owner never mentioned it. It just seems odd that any time one part was changed it ran for a short time. Any suggestions?
#2
12-10-2011, 08:43 AM
I watched "Christine" last night. Now I am convinced that cars have souls. Your story is just as mysterious as Steven King's! In fact I read it a few times. I can't figure out your car. What really puzzles me is that you say: there is spark AFTER the engine STOPS. What triggers that spark?
I don't know if the '02 has a distributor. If my '98 did that to me I would check that distributor top to bottom.
I would also check the coil pack. Any hint of a crack, uneven coloration at the towers, any hint of doubt, I would replace it together with the wires and plugs (cap and rotor if applicable). I know you checked the gaps, but there is more to plugs than that. The coil pack could have internal shorts and throw the computer for a loop.
Other than that I am speculating that the computer gets conflicting data and protects either the ignition system or the injector system by disabling it.
Take care J_Hawk, Christine can be mean!
I don't know if the '02 has a distributor. If my '98 did that to me I would check that distributor top to bottom.
I would also check the coil pack. Any hint of a crack, uneven coloration at the towers, any hint of doubt, I would replace it together with the wires and plugs (cap and rotor if applicable). I know you checked the gaps, but there is more to plugs than that. The coil pack could have internal shorts and throw the computer for a loop.
Other than that I am speculating that the computer gets conflicting data and protects either the ignition system or the injector system by disabling it.
Take care J_Hawk, Christine can be mean!
Last edited by tanprotege; 12-10-2011 at 08:45 AM.
#3
12-11-2011, 07:13 PM
The symptoms remind me of a bad ignition module in a distributor, unfortunately this model has coil on plug ignition and I don't find an "ignitor" like a Toy Yoda. I have considered conflicting data from a sensor but I cant figure from what. I don't have a lab scope to check wave forms so all I have to go by is a little bit of data from the scan tool that appears normal. I don't know if this model substitutes data like some vehicles if a sensor goes bad but without a code to go by I'm lost. I was hoping maybe some one on this forum may have had this problem before and could give me an idea of what to look for. It seems to me that maybe the new ECM has failed already but I'm not sure why, could the transmission range sensor cause an ECM failure? If so, shouldn't it throw a code with just KEY ON; ENGINE OFF instead of having to drive it and wait for the trans to mess up? I'm guessing the ECM controls the transmission so I could see maybe a trans solenoid failure creating problems but wouldn't throw some other code besides a range sensor? If it is a problem in the transmission then that would make all the other previous repairs that worked just a coincidence?
#4
12-12-2011, 09:42 AM
We think alike, J_Hawk. But I am not experienced enough to get you further. There are some online services for $$ that could be worthwhile to you. Here is one:
Mazda repair questions? Ask a mechanic and get answers ASAP
Good luck!
Mazda repair questions? Ask a mechanic and get answers ASAP
Good luck!
Thread
Thread Starter
Forum
Replies
Last Post
