No Spark... Need some Help
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No Spark... Need some Help
My 91 f150 302 just quit running. It gets fuel. I can hear the pump run and there is alot of pressure in the rail. There must not be any spark and I dont know where to start. My coil is only 6 months old and every coil problem ive ever had it gradually went bad, not in a heartbeat. I changed the plugs, wires, cap and rotor not to long after the coil. I heard the ignition modual could have went bad. I dont have any experiance with those, are they expensive? What other things should I be checking?
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From: Easton,Ks
Do the fuel pumps run all the time the key is on and the engine is not running or do they just run for one second and quit?
I have no idea why you would smell gas doing that as if you do not have spark (TFI or PIP bad ???) the fuel pumps would not run and the injectors would not spray.
With the above information:
The only two scenarios I can think of is you would have a bad computer keeping the fuel pumps on and a ruptured diaphragm in the fuel pressure regulator allowing fuel to enter the engine.
OR
The fuel pressure regulator is bad and the fuel pressure is way to high making the F/A ratio too rich to burn.
Have you tried to pull the codes yet?
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you would smell gas cause the key is on and its shooting fuel into the cylinders and its not getting burnt. I did try to get the codes but I only i got egr codes that are old and an 11 system pass which i dont know what it means?
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From: Easton,Ks
How come you will not answer:
Do the fuel pumps run all the time the key is on and the engine is not running or do they just run for one second and quit?
You say:
" you would smell gas cause the key is on and its shooting fuel into the cylinders and its not getting burnt."
I take it by saying that you are saying you are getting spark.
As you can not shoot fuel without the ignition coil getting a firing pulse.
From that it sounds like you have a fuel pressure regulator problem then.
Do the fuel pumps run all the time the key is on and the engine is not running or do they just run for one second and quit?
You say:
" you would smell gas cause the key is on and its shooting fuel into the cylinders and its not getting burnt."
I take it by saying that you are saying you are getting spark.
As you can not shoot fuel without the ignition coil getting a firing pulse.
From that it sounds like you have a fuel pressure regulator problem then.
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From: Easton,Ks
After thinking about it for a while you might be able to get the PIP without spark if the TFI module is bad. They can go bad in different ways and the tfi might be leting the pip go by without firing the spark plugs. I would think this to be rare but I guess it could happen.
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I just scanned it again and it threw 18 in there this time. Loss of ignition diagnostic monitor signal to the control module/spark output grounded. What does this mean? And what about the system pass?
I dont have a fuel pressure gauge, I just pushed the thing down with a pen and shot out pretty good.
I dont have a fuel pressure gauge, I just pushed the thing down with a pen and shot out pretty good.
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From: Easton,Ks
It will shoot out at 25 PSI but will not start and run.
You can have 95 PSI and it will shoot out but will not start at all, a member had one of these the other day.
On the system pass if the 11 is from the KOEO test it means that all of the sensors have passed the electrical test and there voltages are inside the range that the computer thinks they should be.
The 18 means the computer saw a PIP, sent out a SPOUT and looked for a IDM and did not get it.
You can have 95 PSI and it will shoot out but will not start at all, a member had one of these the other day.
On the system pass if the 11 is from the KOEO test it means that all of the sensors have passed the electrical test and there voltages are inside the range that the computer thinks they should be.
The 18 means the computer saw a PIP, sent out a SPOUT and looked for a IDM and did not get it.
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From: Easton,Ks
You should always carry a spare TFI Module anyway, I do.
So I would replace the TFI Module and if that does not fix it throw the old one in the glove box and go after that wiring.
When you replace the TFI put a lot white heat xfer grease on it.