Running rich and loss of power. Codes included

Tough94

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I have 94 Mustang GT running super rich randomly. It also runs differently at times. Sometimes it has crackles at higher RPM's and other times it runs normal. Also randomly chops at idle as if it was cammed. Also down on power. Sometimes it runs richer than other times. The exhaust seems to be getting hot as well but coolant and oil temps are fine despite the engine bay also feeling hot. It runs so rich that it lets out pops, crackles, and burbles. The o2 sensors were replaced twice, cleaned the maf sensor twice, and got a carless x pipe because my cats were on their way out, and no major mods.
Cars fuel pressure was fine at around 36.
The codes I pulled are: 172- HEGO (HO2S) sensor fault/lean. 175- HEGO (HO2S) sensor fault/not switching, or fuel system at adaptive limits. 176- HEGO (HO2S) sensor fault/ always lean. 181 - Fuel system at rich adaptive limits at partial throttle/system lean.
Not sure what the issue could be anymore. Any advice?
 

RAU03MACH

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Double check fuel regulator
And vac leaks on the regulator vac tube

I just checked a guys car it had a 100 psi on a test guage
His regulator took a crap
And it's the same thing your going through
 
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Tough94

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Double check fuel regulator
And vac leaks on the regulator vac tube

I just checked a guys car it had a 100 psi on a test guage
His regulator took a crap
And it's the same thing your going through
Regulator stayed at 36 psi will double check soon and get back with the results. Was hoping it was as simple as the regulator.
 

Jon95GT

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Could it be the distributor PIP sensor starting to fail?
 

Flade

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Are you running a CAI? The K&N style Oiled Air filters foul the MAF over time With small amounts of oil. It causes the MAF to read incorrectly. The ECU responds by increasing the fuel. Eventually it can’t increase anymore and throws the codes you are seeing. By that point you are running really rich, and the car starts to run poorly. The solution is to clean the air filter and properly oil it with the minimum amount of oil. Then remove and clean the MAF with MAF/Electronics cleaner (don’t use annything else and don’t touch the MAF sensor wire) Unplug the battery for 30 mins to clear memory. Put the MAF back in after it is totally dry. Install the air filter, connect the battery and test drive the car.
 
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Tough94

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Are you running a CAI? The K&N style Oiled Air filters foul the MAF over time With small amounts of oil. It causes the MAF to read incorrectly. The ECU responds by increasing the fuel. Eventually it can’t increase anymore and throws the codes you are seeing. By that point you are running really rich, and the car starts to run poorly. The solution is to clean the air filter and properly oil it with the minimum amount of oil. Then remove and clean the MAF with MAF/Electronics cleaner (don’t use annything else and don’t touch the MAF sensor wire) Unplug the battery for 30 mins to clear memory. Put the MAF back in after it is totally dry. Install the air filter, connect the battery and test drive the car.
It has a BBK CAI and tried cleaning the MAF already with no lucky unfortunately. Might try cleaning the filter as well and disconnecting the battery. But since the idle also surges I don't believe that's the issue.
 

duh09

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Honestly don't even know what a distributor PIP sensor is so I will try and do some research on that. Thanks.

Distributor pickup basically. They are replaceable but it's usually a lot easier to toss a brand new distributor in versus trying to pull them apart and rebuild one. When I've had PIP failures, it was no spark at all - not really lining up with what you've got going on.


What all is done to the car? Any mods beyond the CAI and catless midpipe?
 
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Tough94

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Distributor pickup basically. They are replaceable but it's usually a lot easier to toss a brand new distributor in versus trying to pull them apart and rebuild one. When I've had PIP failures, it was no spark at all - not really lining up with what you've got going on.


What all is done to the car? Any mods beyond the CAI and catless midpipe?
It's been rebuilt on a new block but besides that no other mods.
 

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