Re: Error codes
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
"LVDonkey" <email@example.com> wrote in message
> 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
> 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