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I have a 1995 Chrysler New Yorker 3.5 V6 with 138,000 miles & has been a beauty for 3 years now!

Fuel has been leaking into my oil ever since I had my fuel injectors replaced (with OEM injectors after I initially bought re-manufactured ones).
This in return has caused oil pressure issues especially during deceleration.
This fix could be a simple PCM issue (relearn) but highly doubt it. (Fuel injection sync?)
If you would like any further information for diagnosis and advice I'll gladly oblige.

obd1 codes 12,54,55
where do I go from here? (I do have the repair manual.)
Thank you in advance
looking forward to finding solutions to this problem & applying them.
 

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Welcome to Allpar. How is fuel pressure? Does it rapidly fall after shutting down the engine? Is a restart difficult where you have to press down on the gas pedal to start (rich)?
These plastic fuel rails were known to crack and leak (internally or externally). There was a recall #790 for them long ago.
Sometimes the rail reinforcement didn't hold and it was best to replace the right rail (the side with the fuel pressure regulator at the rear).
Code 54 may be fuel sync. This is calculated by the cam/crank position sensor relationship to find #1 TDC. Is the timing belt adjusted OK with the marks lining up?
 

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Greetings Imperial Crown,
Yes it does have a rough restart (when warm). & exactly, a little pressure on the gas does help it start as well...
The rail reinforcement is something I'll look into ASAP (maybe tomorrow). (PAIN in the [I should have my mouth washed out with soap for using such terms] since it is under the intake manifold!)

The timing should be aligned properly since the belt etc was replaced at 120,000 miles & hasn't been an issue.
 

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. . . Fuel has been leaking into my oil ever since I had my fuel injectors replaced (with OEM injectors after I initially bought re-manufactured ones).
This in return has caused oil pressure issues especially during deceleration.
This fix could be a simple PCM issue (relearn) but highly doubt it. (Fuel injection sync?)
If you would like any further information for diagnosis and advice I'll gladly oblige. . . . .
Use a scan tool and view the fuel trim values and oxygen sensor values with the engine running. If the injectors are leaking while the engine is running I would think that you would show rich oxygen sensor value (greater than 0.45 volts) constantly with no switching between rich and lean. If the fuel trim is showing constant negative values then you have a rich running condition and the PCM (powertrain control module) is taking away fuel to attempt to get the air-fuel mixture back to stoichiometric condtions (neither rich nor lean).
 

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Discussion Starter #5
Use a scan tool and view the fuel trim values and oxygen sensor values with the engine running. If the injectors are leaking while the engine is running I would think that you would show rich oxygen sensor value (greater than 0.45 volts) constantly with no switching between rich and lean. If the fuel trim is showing constant negative values then you have a rich running condition and the PCM (powertrain control module) is taking away fuel to attempt to get the air-fuel mixture back to stoichiometric condtions (neither rich nor lean).
I would love to have easy access to a drb3 scan tool! But I don't at the moment therefore can't measure fuel trim percisely but I am getting very low mpg. a rich condition and lack of stoichiometric balance sounds very accurate.
 

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. . . I would love to have easy access to a drb3 scan tool! But I don't at the moment therefore can't measure fuel trim percisely but I am getting very low mpg. a rich condition and lack of stoichiometric balance sounds very accurate. . . .
You do not need a specific scan tool such as DRB III. Most basic scan tools (not code readers) will monitor and display fuel trim and oxygen sensor values along with diagnostic code retrieval. Key element for a scan tool is one that can read and connect to OBD I Chrysler. OBD I had manufacturer specific cables for connection.

As I C mentioned in post #2 dated June 17, 2019 at 5:45 pm, check the fuel system pressure. Attached image shows the location of the fuel pressure regulator. In the note there is mention that a leaking vacuum hose at the pressure regulator will skew its operation and result in higher than desired fuel pressure. Excessive fuel pressure will cause normal functioning fuel injectors to over-fuel and create a rich condition. You can rent a fuel pressure tester at most auto parts retailers for a small deposit. Connect to fuel rail and start and run engine. Operational fuel pressure is 39 psi.

Fuel Pressure Regulator.gif
 

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The right rail reinforcement was only effective if the rail wasn't cracked yet. It added strength to the rail to help prevent cracking from starting.
This recall and recall parts may no longer be available. This may be a rail issue and not an injector issue. Use new o-rings and lube when reassembling.
A leaking rail would usually unbalance fuel trims between bank 1 and bank 2, where one bank would be normal and the other very negative (PCM trying to reduce excessive fuel).
The OBD1 diagnostic connector for LH is a 6 or 8 terminal under the drivers side dash:

 

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Discussion Starter #8
The right rail reinforcement was only effective if the rail wasn't cracked yet. It added strength to the rail to help prevent cracking from starting.
This recall and recall parts may no longer be available. This may be a rail issue and not an injector issue. Use new o-rings and lube when reassembling.
A leaking rail would usually unbalance fuel trims between bank 1 and bank 2, where one bank would be normal and the other very negative (PCM trying to reduce excessive fuel).
The OBD1 diagnostic connector for LH is a 6 or 8 terminal under the drivers side dash:

Thank you for the insight.
I'll do my best to get an equivalent scan tool to test fuel trim and ho2 info.
I'll also follow up when I test fuel pressure.
 

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Discussion Starter #9
The right rail reinforcement was only effective if the rail wasn't cracked yet. It added strength to the rail to help prevent cracking from starting.
This recall and recall parts may no longer be available. This may be a rail issue and not an injector issue. Use new o-rings and lube when reassembling.
A leaking rail would usually unbalance fuel trims between bank 1 and bank 2, where one bank would be normal and the other very negative (PCM trying to reduce excessive fuel).
The OBD1 diagnostic connector for LH is a 6 or 8 terminal under the drivers side dash:
I highly doubt the recall is still valid but will give a call around.
I'm wondering... If the fuel rail is leaking internally how would that cause fuel to dilute the oil? Is it leaking through the injector & further downward or...?
Sorry, I haven't gotten to test fuel pressure or scan the engine performance through a CPU yet either.
 

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You do not need a specific scan tool such as DRB III. Most basic scan tools (not code readers) will monitor and display fuel trim and oxygen sensor values along with diagnostic code retrieval. Key element for a scan tool is one that can read and connect to OBD I Chrysler. OBD I had manufacturer specific cables for connection.

As I C mentioned in post #2 dated June 17, 2019 at 5:45 pm, check the fuel system pressure. Attached image shows the location of the fuel pressure regulator. In the note there is mention that a leaking vacuum hose at the pressure regulator will skew its operation and result in higher than desired fuel pressure. Excessive fuel pressure will cause normal functioning fuel injectors to over-fuel and create a rich condition. You can rent a fuel pressure tester at most auto parts retailers for a small deposit. Connect to fuel rail and start and run engine. Operational fuel pressure is 39 psi.
Thank you for the OBD1 scan tool pointers.
I'll check the pressure asap
 

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Discussion Starter #11
The right rail reinforcement was only effective if the rail wasn't cracked yet. It added strength to the rail to help prevent cracking from starting.
This recall and recall parts may no longer be available. This may be a rail issue and not an injector issue. Use new o-rings and lube when reassembling.
A leaking rail would usually unbalance fuel trims between bank 1 and bank 2, where one bank would be normal and the other very negative (PCM trying to reduce excessive fuel).
The OBD1 diagnostic connector for LH is a 6 or 8 terminal under the drivers side dash:

I'm preparing to dive in & repair this internal fuel rail leak since the recall was "already done on this vehicle."
would you suggest that I go with a new after market fuel rail or simply reinforce the existing rail. I know that it has to be physically assessed before I know what specific area to reinforce. I've have access to the #790 recall repair instructions.
Seems like a daunting task to patch/bond the rail without replacing it but I LOVE this car!!! Any further advice would be appreciated.
 
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