So I just pulled the codes from the computer on my 92 Mustang 5.0 and I got a code 96, which is a "fuel pump secondary circuit failure". Can someone tell me what the fuel pump secondary circuit is? Is this a part that can be replaced? Is it a relay? What is a "secondary circuit"? And will this circuit failure cause poor fuel mileage?
EEC-IV Trouble Code 96
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it means the fuel pump relay didn’t turn on when expected.
Does the car run now? If so, it’s likely an old code. Erase the codes and pull them again and it will likely be gone.
Does the car run now? If so, it’s likely an old code. Erase the codes and pull them again and it will likely be gone.
The car runs great. There's no indication that there's a problem other than the 
ty fuel mileage it's suddenly getting, which I believe I know what the problem is (dirty MAF sensor due to spraying too much oil on the air filter when I cleaned it). I've used 2/3 of a tank of gas and have only went 90 miles. This has been all city driving, but I haven't been hot rodding it, just normal driving. The fuel mileage issue is why I pulled the codes. I wanted to see if there was a problem that was causing the crappy fuel mileage. So when I pulled the codes, code 96 popped up.
Other than a BBK 70mm throttle body & cold air intake that I installed many years ago, it's a stock 5.0 & five speed. I just got done rebuilding the heads & installing a new clutch, timing chain, high volume oil pump and rear main seal. The only mod I did when I did the head rebuild was to eliminate the front two cats (car has 4 cats on it). I doubt eliminating 2 cats would make the fuel mileage go in the toilet. I would assume it would do the opposite. But who knows.
I just ordered a new BBK air filter last night to replace the one I soaked with too much oil (there was a puddle of oil sitting in the intake tube right in front of the MAF sensor). I also have some MAF sensor cleaner that I used on the MAF sensor last night. Once the air filter arrives Sunday, I'll put it on and go fill up the gas tank and drive the car for another week or two and see if that resolves the problem.
On another note, does anyone know exactly what the MAF sensor cleaner is? It smelled exactly like brake cleaner. Or is it something different?
ty fuel mileage it's suddenly getting, which I believe I know what the problem is (dirty MAF sensor due to spraying too much oil on the air filter when I cleaned it). I've used 2/3 of a tank of gas and have only went 90 miles. This has been all city driving, but I haven't been hot rodding it, just normal driving. The fuel mileage issue is why I pulled the codes. I wanted to see if there was a problem that was causing the crappy fuel mileage. So when I pulled the codes, code 96 popped up.Other than a BBK 70mm throttle body & cold air intake that I installed many years ago, it's a stock 5.0 & five speed. I just got done rebuilding the heads & installing a new clutch, timing chain, high volume oil pump and rear main seal. The only mod I did when I did the head rebuild was to eliminate the front two cats (car has 4 cats on it). I doubt eliminating 2 cats would make the fuel mileage go in the toilet. I would assume it would do the opposite. But who knows.
I just ordered a new BBK air filter last night to replace the one I soaked with too much oil (there was a puddle of oil sitting in the intake tube right in front of the MAF sensor). I also have some MAF sensor cleaner that I used on the MAF sensor last night. Once the air filter arrives Sunday, I'll put it on and go fill up the gas tank and drive the car for another week or two and see if that resolves the problem.
On another note, does anyone know exactly what the MAF sensor cleaner is? It smelled exactly like brake cleaner. Or is it something different?
It might be formulated differently but usually it’s a cleaning agent that evaporates quickly such as isopropyl alcohol and other types of VOCs
Carb cleaner, brake cleaner, MAF cleaner probably contains mostly the same stuff but there might be slight differences depending on intended use.
None of those compounds are safe to breathe so try not to.
Carb cleaner, brake cleaner, MAF cleaner probably contains mostly the same stuff but there might be slight differences depending on intended use.
None of those compounds are safe to breathe so try not to.
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Thanks for the info.....
So am I correct to assume the code 96 has nothing to do with my crappy fuel mileage or is causing any issues? Am I ok to ignore the code and not worry about it?
What about the elimination of 2 cats? Is that causing any negative affects with anything? Or is it helping by not having an exhaust flow restriction? I assume that since I still have 2 cats in the exhaust system, it will still pass an emissions inspection???
So am I correct to assume the code 96 has nothing to do with my crappy fuel mileage or is causing any issues? Am I ok to ignore the code and not worry about it?
What about the elimination of 2 cats? Is that causing any negative affects with anything? Or is it helping by not having an exhaust flow restriction? I assume that since I still have 2 cats in the exhaust system, it will still pass an emissions inspection???
How did you run the codes? Did you pull codes with engine off or did you start the car and pull the engine running codes?
I would erase the code in case it’s an old code, and do a drive and then pull them again.
I would erase the code in case it’s an old code, and do a drive and then pull them again.
These pre-OBD cars require the engine codes to be read with the engine off, and then with the engine started. You will get a different set of codes. The engine running codes will likely give you the code causing your rich condition.
Inwould rerun them again in both the engine off and engine running state.
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