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Error codes

I'm having a problem with my 93 5.0.. it starts and runs fine, but around 3/4 throttle or more it noses over and dies.. backfires until you get off the gas. I just pulled the codes today.. I'm getting codes

18, 41, 91. I also ran the cylinder balance test and everything was fine there. My o2 sensors have about 6k miles on them so I'm going to go ahead and assume they are operating ok. As for code 18, is that specifically the spout connector or the TFI?? What do I need to replace on that one? As for 41, and 91 both indicate lean mixture and 91 a fuel pressure problem. I disconnected the vacuum line from the FPR and took it for a drive and it didn't change at all, so can I go ahead and assume that the pressure regulator is the faulty component or could it still be fuel pump/injector related even though it passed the cylinder balance test?
Reply to
LVDonkey
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I think thet you're misunderstanding some of this stuff.... and then you're goig to compound the error with assumptions.

DTC 18 can be set when a poorly maintained ignition system starts arcing and sparking under the hood. Since this makes us real familiar with misfires, we can deduce that these misfires are leaving a lot of oxygen free to go down the pipe to be read by the sensors and PCM as a lean mixture (DTCs 41 and

91). In 1993, engine control systems weren't smart enough to know if they were misfiring or not.

DTCs are a symptom and not a flat "replace component X" statement.

For your case, I would recommend a good basic ignition tune up including cap, rotor and wires with close attention being paid to the condition of the ignition coil.

Reply to
Jim Warman

Could it be a dirty fuel filter?

Reply to
Robert A. Plourde Jr.

I initially thought it was the coil too, which I replaced a week ago, the plugs and wires and cap and rotor were all replaced about 2 weeks before that, the fuel filter has not however, I guess I will also try that this weekend when I have some free time. The car has been sitting for a while due to this problem and I just remembered now how this all started, I had 2 plug wire looms break and 2 plug wires ended up on the headers and burned through, which obviously caused misfiring however when I replaced the wires it didn't go away which is when I replaced basically the whole ignition system. Also this problem is much worse at cold startup.. basically any throttle makes it want to die, I have to wait till my A/F gauge starts bouncing around before pulling out of my parking spot.

Reply to
LVDonkey

How was it running before you replace the all those parts?

Reply to
Ironrod

It ran great before the plug wire incident, after that happened is when I started replacing the ignition parts.

Ir> How was it running before you replace the all those parts?

Reply to
LVDonkey

You're going to have to go into more detail about the plug wire incident. If the car was running decent before you started replacing stuff, try putting the old parts back on and see it the problems clear.

Reply to
Ironrod

Info in dribs and drabs is good..... The plug wire incident is when the wires burned through on the headers? Are the wires assigned correctly for the fring order?

Reply to
Jim Warman

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