fuel system troubles

1999 Plymouth Grand Voyager 3.3 flex fuel model...

I've had some trouble with this van's fuel delivery. The engine doesn't
idle. It can be kept running only at a higher throttle setting. Also,
it makes clouds of unburned gasoline from the exhaust.

I found that after running it for a while, the exhaust manifold is cold
at cylinder #2 and finger burningly hot at #6. Also, with my wife
keeping the engine running, when I pull the wire off of plug #6 the
engine suffers, but pulling #2 or #4 has no effect. The wires will
deliver big fat sparks to the engine block as well as the head of the
spark plug, but obviously the spark is not doing anything in the engine.

My assumption was that #2 and/or#4 injectors are delivering way too much
fuel. So my next test was to pull these two injector wires. When I do
that, the engine will idle (poorly of course because of the dead
cylinders). I assumed at first that the problem was in #2, then I
thought it might be in 2 and 4, but then I tried leaving #2 in place and
pulling #4, and it improved the situation enough to allow the engine to
idle.

Further testing showed that all 6 injectors had the proper clicking
sound with a stethoscope. Checking the system with a scan tool shows no
codes.

Questions for inquiring minds that want to know:

Would excessive fuel pressure set a fault code in the computer? If not,
I'll get a fuel pressure gauge and test it. Otherwise, I could assume
that one or possible two injectors are stuck open even though they are
getting the proper signal indicated by clicking noises.
Assuming that I have one or two bad injectors, can they be cleaned and
fixed, or do they have to be replaced? The reason I ask is because they
cost $75 each, they have to be ordered, and they won't arrive until
Monday. If the ones I have can be rehabilitated I'll give it a try.
One other thing, can anybody think of anything else that would cause
this problem besides a drooling fuel injector? Before I started
scrutinizing the injectors I had thought that it might be a vacuum leak,
but I can't find a leak anywhere.

Are you sure that all 6 ignition wires are routed to the right plugs? Is
the coil pack functioning properly and are the ignition wires good? Have
you tried replacing the spark plugs that are not firing? What condition
were the tips in when you pulled them? Is the Check Engine light
illuminated and are there any engine computer codes set?

Bob

"Robert Reynolds" > wrote in message
...
> 1999 Plymouth Grand Voyager 3.3 flex fuel model...
>
> I've had some trouble with this van's fuel delivery. The engine doesn't
> idle. It can be kept running only at a higher throttle setting. Also, it
> makes clouds of unburned gasoline from the exhaust.
>
> I found that after running it for a while, the exhaust manifold is cold at
> cylinder #2 and finger burningly hot at #6. Also, with my wife keeping
> the engine running, when I pull the wire off of plug #6 the engine
> suffers, but pulling #2 or #4 has no effect. The wires will deliver big
> fat sparks to the engine block as well as the head of the spark plug, but
> obviously the spark is not doing anything in the engine.
>
> My assumption was that #2 and/or#4 injectors are delivering way too much
> fuel. So my next test was to pull these two injector wires. When I do
> that, the engine will idle (poorly of course because of the dead
> cylinders). I assumed at first that the problem was in #2, then I thought
> it might be in 2 and 4, but then I tried leaving #2 in place and pulling
> #4, and it improved the situation enough to allow the engine to idle.
>
> Further testing showed that all 6 injectors had the proper clicking sound
> with a stethoscope. Checking the system with a scan tool shows no codes.
>
> Questions for inquiring minds that want to know:
>
> Would excessive fuel pressure set a fault code in the computer? If not,
> I'll get a fuel pressure gauge and test it. Otherwise, I could assume
> that one or possible two injectors are stuck open even though they are
> getting the proper signal indicated by clicking noises.
> Assuming that I have one or two bad injectors, can they be cleaned and
> fixed, or do they have to be replaced? The reason I ask is because they
> cost $75 each, they have to be ordered, and they won't arrive until
> Monday. If the ones I have can be rehabilitated I'll give it a try.
> One other thing, can anybody think of anything else that would cause this
> problem besides a drooling fuel injector? Before I started scrutinizing
> the injectors I had thought that it might be a vacuum leak, but I can't
> find a leak anywhere.

Bob Shuman wrote:
> Are you sure that all 6 ignition wires are routed to the right plugs?

Now that you mention it, I haven't checked that but I have no reason to
believe that they are wrong. Disconnecting #4 injector wire improves
running, so I don't suspect the ignition system. I will be checking
this, though.


> Is the coil pack functioning properly and are the ignition wires good? Have
> you tried replacing the spark plugs that are not firing?


Brand new plugs and wires, just finished this job yesterday. I noticed
that #4 makes bigger sparks than #2, but I don't know what that means in
this situation.


> What condition
> were the tips in when you pulled them?

They looked pretty worn, but now the plugs are new.


> Is the Check Engine light
> illuminated and are there any engine computer codes set?
>
> Bob


No light and no codes.

Bob Shuman wrote:
> Are you sure that all 6 ignition wires are routed to the right plugs?

I checked to make sure, and the wires are indeed routed correctly.

As bad as this vehicle is running the check engine lite should be on!!! you
mention nothing about this or even checking for fault codes.
I would think that by disconnecting the #4 injector and the fact that is
smooths out some would be the injector driver circuit is causing the
injector to remain open and dumping in to much fuel. The injector gets 12v
from the ASD relay and is grounded by the PCM. make sure the wire from the
injector (ground) to the pcm is not shorted to ground. If this were the
case a #4 injector circuit fault code would have been generated.

Just a thought

Glenn Beasley
Chrysler Tech

If you were to trace the wire from the injector to the PCM. disconnect the
injector#4 connector and the PCM C1 connector (LB/BR pin 16 ) and check
for a short to ground

Glenn

damnnickname wrote:
> As bad as this vehicle is running the check engine lite should be on!!! you
> mention nothing about this or even checking for fault codes.
> I would think that by disconnecting the #4 injector and the fact that is
> smooths out some would be the injector driver circuit is causing the
> injector to remain open and dumping in to much fuel. The injector gets 12v
> from the ASD relay and is grounded by the PCM. make sure the wire from the
> injector (ground) to the pcm is not shorted to ground. If this were the
> case a #4 injector circuit fault code would have been generated.
>
> Just a thought
>
> Glenn Beasley
> Chrysler Tech
>


I did mention that there were no fault codes, and that the injectors
click as they should, indicating that they are getting a pulsating
signal. I forgot to mention the absence of the check engine light.

I don't know about 1999, but in the 96 model year the fuel pressure is
definitely NOT monitored by the computer. It can run from zero to
infinity and it won't set a fault code. I would not be surprised if
your pressure is too high, caused by a blocked return line, or
regulator system malfunction.

On Feb 22, 6:18�pm, Robert Reynolds > wrote:
> 1999 Plymouth Grand Voyager 3.3 flex fuel model...
>
> Questions for inquiring minds that want to know:
>
> Would excessive fuel pressure set a fault code in the computer? *If not,
> I'll get a fuel pressure gauge and test it. *Otherwise, I could assume
> that one or possible two injectors are stuck open even though they are
> getting the proper signal indicated by clicking noises.
> Assuming that I have one or two bad injectors, can they be cleaned and
> fixed, or do they have to be replaced? *The reason I ask is because they
> cost $75 each, they have to be ordered, and they won't arrive until
> Monday. *If the ones I have can be rehabilitated I'll give it a try.
> One other thing, can anybody think of anything else that would cause
> this problem besides a drooling fuel injector? *Before I started
> scrutinizing the injectors I had thought that it might be a vacuum leak,
> but I can't find a leak anywhere.

It would set a fault code if the fuel pressure was to high or to low. P0171
P0172 1/1 fuel system lean and 1/1 fuel system rich. But does not just
point to the fuel pressure. It wont just condemn the fuel pressure. You
would still have to check the basics for this code such as coolant temp,
mechanical problems and upstream 02 sensors

Glenn

squirt water all over the work you did including the coil to make sure none of
the wires are shorting out and then inspect the one plug for the cylinder you
have in question to make sure it is firing and if it is soaked by fuel why?

damnnickname wrote:

> It would set a fault code if the fuel pressure was to high or to low. P0171
> P0172 1/1 fuel system lean and 1/1 fuel system rich. But does not just
> point to the fuel pressure. It wont just condemn the fuel pressure. You
> would still have to check the basics for this code such as coolant temp,
> mechanical problems and upstream 02 sensors
>
> Glenn