Engine? Problem-92 3.3 V6

Hello! I have had a nearly flaless 3.3 v-6 in my 92 Voyager. Before I
took a recent trip from NE Nevada to Portland, I thought I detected a
noisy lifter. Days after I returned, the noise was louder (not
deafening). I drove into town (14 miles) and one top mechanic said I
had a loose wristpin. He ruled out a lifter. Before going home, I made
another stop. Then as I was preparing to go home, the 'Check Engine'
light came on and the van started running a bit rough. I decided
before it died to drive SLOWLY back home on the Interstate.

I beached the car for two months and started it this afternoon. No
'Check Engine ' light, but after it warmed up, the tapping noise
returned. I was advised to try and put it in gear (s) and see what
happened. Out of P to reverse, back to P and the noise disappeared!
Put into a forward drive or reverse, the noise is apparent. Nothing in
P or N. Rev the engine and the noise returns at about 25K RPM. There
is no loss in oil pressure; car does not overheat. I hate the thought
of putting another engine in this van, as I did this last year. There
is a slight vibration now, which I thought might be a bad spark plug
wire. It appeared as the 'Check Engine' appeared. Today, in starting
it, I ran it for a half hour and no 'Check Engine" light

I thought it might be the power steering pump, but have ruled it out.
Another mechanic friend said it might be in the bellhousing, ie, loose
converter bolts. Is there such noise that can come from the converter?
I had previously towed a vehicle from Portland to NE Nevada. There is
no change in the transmission. It shifts fine, fluid recently changed,
along with filter.

Any and all help is Appreciated. I miss driving this beauty.

 

From what you are describing and me not being able to hear the noise I would
say that the flex plate that connects the engine to the transmission is
split.
That normally sounds like an internal engine problem such as a piston/wrist
pin and comes and goes just as you said by going from reverse to drive.
You would have to tell me what the fault code is in the computers memory to
be able to give you any info about the check engine lite.

 

From what you are describing and me not being able to hear the noise I would
say that the flex plate that connects the engine to the transmission is
split.
That normally sounds like an internal engine problem such as a piston/wrist
pin and comes and goes just as you said by going from reverse to drive.
You would have to tell me what the fault code is in the computers memory to
be able to give you any info about the check engine lite.

 

During the half hour I ran the car yesterday, the check engine light
did NOT come on. I will scan the computer and see if anything may have
been retained.

From your response, I'm more convinced it is not an engine problem,
but your diagnosis is right on with the tranny flex plate. A friend
who is an ASE mechanic, first came the same diagnosis, so now we
separate the engine and tranny and go from there.

Thank You for your time and help.