Chrysler Repair: 1988 new yorker 3.0L v6: codes 13, 27, 42


Question
QUESTION: i have a 1988 chrysler new yorker 3.0L v6 its been a nightmare i just replaced fuel tank and fuel pump filter and fuel lines due to rust. now it only starts if you push down on the accelerator a little it runs for awhile then dies then gas pours out the throttle body what would cause this flooding?

ANSWER: Hi Kenny,
As this has a multi-point fuel injector set-up with individual injectors and fuel rails for fuel to flood out of the throttle body suggests either that the fuel pressure is much higher than it should be or the one or more of the injectors is stuck open so there is excess fuel getting into the intake manifold. You might first try for a fault code by turning the ignition switch "on-off-on-off-on and leave on" doing that in 5 seconds or less elapsed time. Then watch the check engine light, which remains "on", to see it the begin to flash, pause, flash, etc.  Count the number of flashes before each pause. The repeat the process to be sure of an accurate set of flash counts. Let me know the results and we'll go from there.
Roland

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QUESTION: in reference to my flooding issue it was the fuel pressure regulator i replaced it now car acts like firing order is wrong like it keeps changing what it need to be? i pulled fault codes from lamp here are the codes 13,27,42 is it possible all three items are bad or do you think i have major wiring problems? Thank you again for your help i'm so frustrated with this car!

ANSWER: Hi Kenny,
The 13 code says the manifold pressure sensor voltage is not changing as it should. Test for 5 volts to be present on the violet trace wire, and whether the voltage measured between the other two wires is varying as you manipulate the throttle, which it should. Use fine straight pins to pierce the wire insulation.
The 27 code says that one or more of the three "drivers" for the fuel injectors is not responding so check the spark plugs to see if any pair of them look wet.
The 42 code says that the autoshutdown relay is either not working or has bad internal points so try substituting if for another relay of the same part number that is not crucial to the operation and see if that helps the operation.
It is possible that all three are present but I doubt major wiring issues absent some sort of history. What is the history of the problems/vehicle? Did it run right and then all went bad?
Try disconnecting the battery briefly to erase all the codes (but that will "set" a code 12) and then run it again and check for fresh codes.
Roland

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QUESTION: Thank you for your help. as to the history of car it started shutting off when coming to a stop but would restart it was intermittent at first but slowly got worse. so the car was parked for about 7 yrs now. its my dads car he really likes it so im trying to get up and running again. i've replaced timing belt before the shutting down issues. just recently replaced plugs and cap rotor and wires,fuel pressure regulator,fuel pump. thats all for now its back firing intermittent out the exhaust then out the intake i'm using firing order 123456. also tryed 135462 which doesn't work? im confused on the injector codes coming up that wouldn't cause backfiring?

Answer
Hi Kenny,
The firing order it 123456 but that is not the order of the wires at the distributor cap itself due to internal re-wiring in the cap itself. The wires are supposed to be 135462 going counter clockwise with the 1 wire facing toward the rear of the vehicle.
As to the original problem of it dying when coming to a stop, I would try checking out the exhaust gas recirculation valve (egr) to see if the valve stem might be cruddy and preventing the valve from closing to a dead stop which it has to do when slowing down to an idle. Notice the stem is behind a flange that separates the round vacuum cap from the valve body. It has a slot into which you can insert the tip of a screwdriver that allows you to move the stem back and forth, against a spring-action that tries to close the valve. Spray some WD-40 on the stem where it enter the valve body, and then exercise the stem some more to be certain of free movement to a dead stop. That too will help with starting and idling.
Then let me know if that improves anything. Check for any wet pairs of spark plugs that would corroborate a possible injector problem. And check the voltage on the MAP, and try changing the ASD relay with a similar numbered non-essential relay.
Roland