Won't start
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Won't start
Hi,
My 1990 F150 with a 5.0L V8 died in the driveway, and will not start. The fuel pump comes on and primes, runs while cranking. The fuel pump is less than a year old.
I checked for a spark, and am not getting one. The distributor cap and rotor are new, and the plug wires are new also. I installed a new TFI ignition module on the distributor, and have examined, but have not tested any of the internal distributor components.
I am suspicious of the coil. I just over 11 volts coming to the coil. I pulled it out and and measured the resistance of the primary (0.5 Ohms) and the secondary coils (8.95K Ohms) The secondary measurement seems suspect given that the specs for aftermarket coils appear to be around 3.1K Ohms. I don't have a service manual, so I don't know.
Thoughts?
My 1990 F150 with a 5.0L V8 died in the driveway, and will not start. The fuel pump comes on and primes, runs while cranking. The fuel pump is less than a year old.
I checked for a spark, and am not getting one. The distributor cap and rotor are new, and the plug wires are new also. I installed a new TFI ignition module on the distributor, and have examined, but have not tested any of the internal distributor components.
I am suspicious of the coil. I just over 11 volts coming to the coil. I pulled it out and and measured the resistance of the primary (0.5 Ohms) and the secondary coils (8.95K Ohms) The secondary measurement seems suspect given that the specs for aftermarket coils appear to be around 3.1K Ohms. I don't have a service manual, so I don't know.
Thoughts?
Fleet Owner
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From: Easton,Ks
If the engine runs when you have the key in the start position and will not run in the run position I would have to say you have a bad Ignition switch (or adj) or wiring from the switch to the Ignition system.
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Thanks.
Subford: Thanks! Sorry I was not clear with respect to the engine and the fuel pump. The engine does not run while I have the key in the start position. What I meant to say was that the fuel pump will come on (and runs while I am trying to start the engine). The engine does not run at all right now. That being said, I will check out your suggestions.
TNT1968: Thanks! I see that the coil may be suspect. I'll see if I can get a new one tomorrow, and let you know about the results.
Subford: Thanks! Sorry I was not clear with respect to the engine and the fuel pump. The engine does not run while I have the key in the start position. What I meant to say was that the fuel pump will come on (and runs while I am trying to start the engine). The engine does not run at all right now. That being said, I will check out your suggestions.
TNT1968: Thanks! I see that the coil may be suspect. I'll see if I can get a new one tomorrow, and let you know about the results.
Fleet Owner
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From: Easton,Ks
The PIP will not stop the pump(s) from running when you ground pin # 6 of the EEC test connector or from running one second when you turn on the key.
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Interestingly, prior to replacing the Ignition Module (TFI) the fuel pump would be coming on and going off almost like there was a short somewhere. As of this point that behavior has not returned.
At this point the PIP does not sound like it is the problem.
Thanks again.
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Fleet Owner
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From: Easton,Ks
Check the Tach (-) side of the Ignition coil with it cranking and see if it flashes.
Look at the Ignition Coils two wire plug very close as this gives a lot of problems.
I would not change the Ignition Coil yet.
You have an "E" coil and not a DS II coil as values was given above. But you are with in those values also.
I just took the values with a meter and got 2 ohms on the primary and 88,000 on the secondary. So it sounds like your coil is good.
You may want to check the wiring under the PCM Power Relay and the Fuel Pump Relays.
Make sure you are getting power to the Fuel Injectors red wire with the key on. Use a test light and not a meter.
Look at the Ignition Coils two wire plug very close as this gives a lot of problems.
I would not change the Ignition Coil yet.
You have an "E" coil and not a DS II coil as values was given above. But you are with in those values also.
I just took the values with a meter and got 2 ohms on the primary and 88,000 on the secondary. So it sounds like your coil is good.
You may want to check the wiring under the PCM Power Relay and the Fuel Pump Relays.
Make sure you are getting power to the Fuel Injectors red wire with the key on. Use a test light and not a meter.
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Right. The coil seems ok. I did a bit of a reset today and double checked a few things. I pulled the SPOUT and checked for a spark (spark plug to ground while son maned the starter switch). Good spark. Pluged in the SPOUT and no spark. From one of your previous posts I believe that this points a finger towards the Computer ("starting woes" thread - I read before starting this thread). https://www.ford-trucks.com/forums/8...ting-woes.html
I shall still check the PCM wiring under the fuel relays, etc for good measure. However, is there any thing else I should double check prior to biting the bullet and replacing the computer?
I shall still check the PCM wiring under the fuel relays, etc for good measure. However, is there any thing else I should double check prior to biting the bullet and replacing the computer?
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From: Easton,Ks
What you are doing by removing the SPOUT shorting bar (jumper) is removing the PCM Computer from Ignition Control and without Computer Control the ICM is on its own. So now the ICM will fire the coil at Base timing (10 deg BTDC) and the engine will run without any advance at all. At this point you are still using the PIP sensor and if the PIP is bad the engine will not run at Base timing.
This is why when you are timing the engine with the SPOUT out you recheck the timing after you put the SPOUT back in to see if it moved. If the timing did not move then you may have bad wiring from the PCM Computer to the ICM.
If the computer is bad in some way it will hold the SPOUT wire to the ICM high or low without a train pluses and the ICM will not fire the Ignition coil at all.
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The ECM was fried!
Hi,
I purchased a rebuilt ECM and installed it. IT RUNS! Whew! Thanks to all.
I have a few different issues which I will share in the forum but want to research what has already been said on those subjects before I go forward with a post.
Also, I will do as SUBFORD suggest with respect to checking the timing to see if it has moved (I timed it to 10 degrees BTC. But I can tell you that it has made a world of difference (understatement of the day), and I will be greatly surprised if the timing has not come under control of the rebuilt ECM.
At any rate, I can get to some of my other pressing chores at this point and monitor the codes the rebuilt ECM provides so as to make those repairs too.
FYI, to other readers of this thread. If you end up replacing your ECM like I did, the old ECM is worth a core charge (in my case $55). So don't bust it open or abuse it. I took a peak inside mine but did not see any outward problems, though the Printed Circuit Board looked like it had a fungus or something in between the layers. I carefully closed it up and was able to return it as a core.
Thanks Again!
I purchased a rebuilt ECM and installed it. IT RUNS! Whew! Thanks to all.
I have a few different issues which I will share in the forum but want to research what has already been said on those subjects before I go forward with a post.
Also, I will do as SUBFORD suggest with respect to checking the timing to see if it has moved (I timed it to 10 degrees BTC. But I can tell you that it has made a world of difference (understatement of the day), and I will be greatly surprised if the timing has not come under control of the rebuilt ECM.
At any rate, I can get to some of my other pressing chores at this point and monitor the codes the rebuilt ECM provides so as to make those repairs too.
FYI, to other readers of this thread. If you end up replacing your ECM like I did, the old ECM is worth a core charge (in my case $55). So don't bust it open or abuse it. I took a peak inside mine but did not see any outward problems, though the Printed Circuit Board looked like it had a fungus or something in between the layers. I carefully closed it up and was able to return it as a core.
Thanks Again!
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