More than likely is is the sender, they are notorious for failure. But you
should double check using a mechanical gauge you can borrow from your local
Auto-Zone.

When you get a replacement make sure it is a sender, not a switch for an
idiot light.

"bushman" <askme@askme.com> wrote in message
news:MiLwg.1509$Ch5.816@tornado.tampabay.rr.com...
>
> "DougW" <post.replies@invalid.address> wrote in message
> news:pcvwg.66860$9c6.8773@dukeread11...
>> bushman wrote:
>>> 2000 6cyl. 45Kmiles
>>> The oil pressure drops to 0 and "check gauges" comes on when warm and
>>> idling. No other problems.
>>> New oil and filter did not help.
>>
>> Loose connection or failing pressure sender.
>> 0 psi indicates the connector has come loose.
>> 80 would indicate a short to ground.
>> http://revbeergoggles.com/instruments/index.html#oil
>>
>> --
>> DougW
>>
> Thanks to everyone. I will try a new sender. The pressure reads normal
> when the engine is cold and just a little low at 1000+rpm when hot. could
> the pressure relief valve be stuck open? If so where is it?
> - Allen
>

 

bushman proclaimed:

> "DougW" <post.replies@invalid.address> wrote in message
> news:pcvwg.66860$9c6.8773@dukeread11...
>
>>bushman wrote:
>>
>>>2000 6cyl. 45Kmiles
>>>The oil pressure drops to 0 and "check gauges" comes on when warm and
>>>idling. No other problems.
>>>New oil and filter did not help.
>>
>>Loose connection or failing pressure sender.
>>0 psi indicates the connector has come loose.
>>80 would indicate a short to ground.
>>http://revbeergoggles.com/instruments/index.html#oil
>>
>>--
>>DougW
>>
>
> Thanks to everyone. I will try a new sender. The pressure reads normal when
> the engine is cold and just a little low at 1000+rpm when hot. could the
> pressure relief valve be stuck open? If so where is it?
> - Allen

It could be, but first just change the sender. I think Jeep got the
original units from Lucas or similar. If your sender filter layout is
the same as a 4.0 ZJ, the hardest part is simply turning the thing--you
only get a very very short stroke with a wrench on each attempt. The
change itself other than that is trivially simple. [Thanks DougW]

 

bushman proclaimed:

> "DougW" <post.replies@invalid.address> wrote in message
> news:pcvwg.66860$9c6.8773@dukeread11...
>
>>bushman wrote:
>>
>>>2000 6cyl. 45Kmiles
>>>The oil pressure drops to 0 and "check gauges" comes on when warm and
>>>idling. No other problems.
>>>New oil and filter did not help.
>>
>>Loose connection or failing pressure sender.
>>0 psi indicates the connector has come loose.
>>80 would indicate a short to ground.
>>http://revbeergoggles.com/instruments/index.html#oil
>>
>>--
>>DougW
>>
>
> Thanks to everyone. I will try a new sender. The pressure reads normal when
> the engine is cold and just a little low at 1000+rpm when hot. could the
> pressure relief valve be stuck open? If so where is it?
> - Allen

It could be, but first just change the sender. I think Jeep got the
original units from Lucas or similar. If your sender filter layout is
the same as a 4.0 ZJ, the hardest part is simply turning the thing--you
only get a very very short stroke with a wrench on each attempt. The
change itself other than that is trivially simple. [Thanks DougW]

 

bushman proclaimed:

> "DougW" <post.replies@invalid.address> wrote in message
> news:pcvwg.66860$9c6.8773@dukeread11...
>
>>bushman wrote:
>>
>>>2000 6cyl. 45Kmiles
>>>The oil pressure drops to 0 and "check gauges" comes on when warm and
>>>idling. No other problems.
>>>New oil and filter did not help.
>>
>>Loose connection or failing pressure sender.
>>0 psi indicates the connector has come loose.
>>80 would indicate a short to ground.
>>http://revbeergoggles.com/instruments/index.html#oil
>>
>>--
>>DougW
>>
>
> Thanks to everyone. I will try a new sender. The pressure reads normal when
> the engine is cold and just a little low at 1000+rpm when hot. could the
> pressure relief valve be stuck open? If so where is it?
> - Allen

It could be, but first just change the sender. I think Jeep got the
original units from Lucas or similar. If your sender filter layout is
the same as a 4.0 ZJ, the hardest part is simply turning the thing--you
only get a very very short stroke with a wrench on each attempt. The
change itself other than that is trivially simple. [Thanks DougW]

 

bushman proclaimed:

> "DougW" <post.replies@invalid.address> wrote in message
> news:pcvwg.66860$9c6.8773@dukeread11...
>
>>bushman wrote:
>>
>>>2000 6cyl. 45Kmiles
>>>The oil pressure drops to 0 and "check gauges" comes on when warm and
>>>idling. No other problems.
>>>New oil and filter did not help.
>>
>>Loose connection or failing pressure sender.
>>0 psi indicates the connector has come loose.
>>80 would indicate a short to ground.
>>http://revbeergoggles.com/instruments/index.html#oil
>>
>>--
>>DougW
>>
>
> Thanks to everyone. I will try a new sender. The pressure reads normal when
> the engine is cold and just a little low at 1000+rpm when hot. could the
> pressure relief valve be stuck open? If so where is it?
> - Allen

It could be, but first just change the sender. I think Jeep got the
original units from Lucas or similar. If your sender filter layout is
the same as a 4.0 ZJ, the hardest part is simply turning the thing--you
only get a very very short stroke with a wrench on each attempt. The
change itself other than that is trivially simple. [Thanks DougW]

 

Allen,

Did the new sensor fix your problem?

Carl

"bushman" <askme@askme.com> wrote in message
news:bhnwg.1858$ik6.557@tornado.tampabay.rr.com...
> 2000 6cyl. 45Kmiles
> The oil pressure drops to 0 and "check gauges" comes on when warm and
> idling. No other problems.
> New oil and filter did not help.
> Thanks - Allen
>

 

Allen,

Did the new sensor fix your problem?

Carl

"bushman" <askme@askme.com> wrote in message
news:bhnwg.1858$ik6.557@tornado.tampabay.rr.com...
> 2000 6cyl. 45Kmiles
> The oil pressure drops to 0 and "check gauges" comes on when warm and
> idling. No other problems.
> New oil and filter did not help.
> Thanks - Allen
>

 

Allen,

Did the new sensor fix your problem?

Carl

"bushman" <askme@askme.com> wrote in message
news:bhnwg.1858$ik6.557@tornado.tampabay.rr.com...
> 2000 6cyl. 45Kmiles
> The oil pressure drops to 0 and "check gauges" comes on when warm and
> idling. No other problems.
> New oil and filter did not help.
> Thanks - Allen
>

 

Allen,

Did the new sensor fix your problem?

Carl

"bushman" <askme@askme.com> wrote in message
news:bhnwg.1858$ik6.557@tornado.tampabay.rr.com...
> 2000 6cyl. 45Kmiles
> The oil pressure drops to 0 and "check gauges" comes on when warm and
> idling. No other problems.
> New oil and filter did not help.
> Thanks - Allen
>

 

Jeep Talk is what I need. I just found this string and joined. I've got
a 99 4.0 with bouncing oil pressure gauge and "check gauges" light
popping on & off. I think it's sending unit as engine runs fine with no
noises. Just where is the thing located? And can I replace it just by
crawling under it?

Thx

Carl wrote:
> Allen,
>
> Did the new sensor fix your problem?
>
> Carl
>
> "bushman" <askme@askme.com> wrote in message
> news:bhnwg.1858$ik6.557@tornado.tampabay.rr.com...
> > 2000 6cyl. 45Kmiles
> > The oil pressure drops to 0 and "check gauges" comes on when warm and
> > idling. No other problems.
> > New oil and filter did not help.
> > Thanks - Allen
> >