Problem with engine vibration on Intrepid...

I have a 2000 Dodge Intrepid ES with the 3.2L V6. Recently I had to
replace the A/C belt because I figured it was getting too hot out. It
had been sitting like that for about 4 months and the system needed to
be charged up. Once that was taken care of the air was blasting nice
and cold.

Unfortunately, I started to notice an intermittent vibration while the
engine would idle. It felt kinda like a Cessna inside the cab. 3 Days
later while I was driving down the highway I started noticing the
vibration. If I turned the car off and then started it back up quickly,
the vibration went away. It also didn't seem to follow the RPMs of the
motor. All of a sudden I lost my A/C and I thought "Oh great,
compressor locked up and I lost the belt". When I got home I opened the
hood and that wasn't the case at all. The belt is still on there. Now,
however, the clutch doesn't seem to want to engage. I went out today
and hooked a wire from ground and from the battery jumper to the
compressor connector and it didn't engage manually. I didn't get a
chance to try a test-light on it to see if there was continuity though.

Something else weird has started happening. When the car is hot I'm
starting to get a different type of vibration while the engine idles
sometimes. It's not such a rhythmic vibration as the first one, but
it's like the whole engine is running really rough. When I look under
the hood I notice the top water hose and the whole radiator are
vibrating violently. When I stop the car and immediately restart it,
all is fine again. I can't tell exactly where the vibration is coming
from and it's really strange that it's intermittent like that. The
compressor clutch isn't engaging or anything because I've had this
happen with the a/c completely off.


Does anyone have any clue as to what could be going on? I'm thinking I
probably have to replace the A/C clutch at this point, how hard is this
for this car? I've got pullers and what-not. Also, I'm wondering if I
should change the water pump and timing belt now, since I've hit 90,000
miles.


Thanks all

Jeff

 

Cant explain why your compressor quit, but if you jumped it as you say you
did, I would guess the coil is bad. Your intermittent vibration could be a
water pump/idler pulley getting ready to take a dump or one of your radiator
fan motors/blades are getting ready to go out.
Depending on how mechanically inclined you are......it is a relatively easy
job to do, both a/c coil and water pump
Glenn Beasley
Chrysler Tech

 

Yes, I've got tools and everything, I just always need a little help in
the troubleshooting department. How do you replace the coil, is it
external to the compressor or do I need to change the clutch while I'm
there?

Also, is there a convenient way to cycle the fans on and off to see if
they are causing the vibrations? Also, if the water pump was bad,
wouldn't the problem stick around if I turned the car off and back on
again? It seems to me like it would be happening all the time and at
approximately the same RPM, which it's not.

Jeff

 

I'm not saying that it is the water pump or the fan, just suggesting what I
see here at the dealer., I would recommend that if the coil is bad to
purchase a reman Complete compressor from your local dealer.
Without the use of a Scan tool I cant see how you would cycle the fan,
except to just watch it turn on when required by the engine controller. Make
sure there is no play in the fan motor/blade when the key is off, that would
be the first start.. A bearing in the pump /fan motor could come and go,
Especially the fan motor, I have seen so many intermittent noises that I
cant pin point when the customer complains about it until it actually is
there all the time.......MOST of the problems are from the fan motor(s)

 

I find the simple expedient of a jumper wire with flat spade connectors
on each end inserted in the appropriate sockets of the fan relay (low
speed or high speed) works great

I store my little jumper wire in an unused relay socket in my wife's
car, and its served me well both as a diagnostic tool whenever I suspect
ANY of the relays of being bad.

 

Just to be clear - you connected one wire from ground (which could be
the negative jump post) to one terminal of the compressor, and another
wire from the positive jump post to the other terminal of the
compressor? I think that's probably what you were saying - I just
wanted to make sure.

RE: vibration:
How long since plugs were replaced? Checked the battery voltage
(positive jump post) with the engine running to see if alt. is charging?
Ever cleaned the throttle body? Could be fan motor bearings going out
as others suggested.

Bill Putney
(To reply by e-mail, replace the last letter of the alphabet in my
adddress with the letter 'x')

 

Well technically all you have to do is pop off the relay cover and push the
contact to activate it

 

Thanks everyone for the replies...

I went out last night and tried testing out the fan. I ran the engine
until it was waaay too hot and guess what, the fan never came on. I
checked the fuse and it was blown, so I moved another good one in the
test it. The fan still didn't come on. Unfortunately, it was getting
late and I wasn't able to get the relay tested, but that's my next
step. It makes more and more sense that the fan was/is trashed since
the radiator was shaking violently. It just didn't occur to me to check
it since I guess it was running all the time (This is Texas, and it's
hot.

The plugs haven't been changed since I've owned the car (32k to 94k
now) so I'm going to change those out soon. I haven't cleaned the
throttle body, but will look at giving that a go over too since I'm
sure it's probably dirty.

Is it really best to go with a complete reman compressor? I would have
to have the system evacuated and all that stuff, plus the cost of the
whole compressor is pretty high. When the system was working, it was
blowing good cold air, and I also put dye in the system. I took my
blacklight out and looked for leaks and I couldn't find any. The
compressor didn't seem to be making noises internally. I checked the
relay for it, by the way, and it seemed to be okay (swapped another one
for it). Still didn't cycle. (And yes, I connected a complete DC
circuit to the compressor connector to test it the other day, and it
didn't engage the clutch, or even click).

I'm going to play with it some more.

 

They must've changed relay vendors if you can do that- the relays in
wife's 93 have a bead of glue holding the cover on them and sealing out
moisture.

 

I've forgotten which YEAR LH car this is, but if its a first-generation
its very likely that the plug WIRES need replacement as much or more
than the plugs.

I'm with you on that one- a clutch coil is a lot easier job than
needlessly replacing a whole compressor.

 

One of the fan motors is locking up and drawing too much current.
Here's a little trick on the LH cars: If the passenger side fan is the
one that is the problem (i.e., the one blowing the fuse), you can
disconnect it electrically at a connector on the fan assembly. Your
engine will cool adequately on just the one (driver's side) fan. This
will keep the fuse from blowing and buy you some time until you can get
a new fan assembly and install it. Just watch your temp gage, and
minimize use of the a.c. - I limped along fine on mine on one fan - even
using the a.c. as normal - for quite a while with no problem. With only
one fan running, the temp. gage stayed where it normally does with both
fans working.

**HOWEVER** - if the driver's side fan is the bad one, then you can't
just disconnect that fan - the connector that suppplies that one
supplies both.

Anyway - just a little trick from the 300M Club that might help you out.

**ALSO** - You can get just the one fan motor to replace the bad one
from the DC dealer. **BUT** you should expect the presently working one
to fail not too far down the road (the fan motors have a finite life).
Any savings from only having to buy the one motor will be eaten up by
the labor of having to do the same work all over again (plus you will
avoid the additional labor of removing the one motor from the assembly.

There is a police version of the fan assembly available from the dealer
- and, believe it or not, it sells for less than the regular version.

Bill Putney
(To reply by e-mail, replace the last letter of the alphabet in my
adddress with the letter 'x')

 

burn't cooling fan and bad fuse