1995 Chrysler New Yorker 3.5 - engine dies

Hello! I’m new to the forum and thought I’d give it a try. We are having
some trouble with my daughter’s 1995 Chrysler New Yorker 3.5.

For a recent no-start problem, we replaced the crankshaft and the camshaft
position sensors and one additional sensor (I can’t recall which one it was
and don’t have a copy of my invoice). The problem turned-out to be a
failed or stuck tensioner for the timing belt. After those repairs, the
car has run flawlessly for a month and about 500 miles.

What’s happening now is that the engine dies upon stopping at a stop
sign/signal. This is inconsistent. Sometimes it happens and sometimes it
doesn’t. If it does die, (so far) it never fails to restart and run
perfectly. Sometimes, if it doesn’t actually die, it’ll “stumble” a
little and then smooth right out. In, say, a five mile trip, this may
happen, at worst, 5 – 6 times . . . . . and, it may not happen at all.
Here at home, it seems to idle without problem (at about 1000 rpm per its
tachometer).

My immediate suspicion was a loose battery cable. That’s been all
checked-out, thoroughly cleaned and re-connected. The problem persists.
The engine is not “throwing” any trouble codes. I have done some
preliminary checking for vacuum leaks and loose connections . . . wiggling
connectors.

I’m probably beyond my own ability a far as diagnosing and repairing this.
What I’m mostly looking-for is your ideas for things that might be suspect
and need further checking. I know, even for a fully-equipped and
experienced mechanic, how difficult this sort-of thing can be unless
somehow it will occur when he actually has if hooked-up to his test
equipment. Any ideas or similar experiences that might help us? Thanks.
Don

 

Sounds like the throttle body has some gunk in it. Clean it.

Ted

 

Thank you. Is there a product I can ad to the fuel, such as fuel injector
cleaner, that will help with this? Don

 

Thank you. Is there a product I can ad to the fuel, such as fuel injector
cleaner, that will help with this? Don

 

No, the throttle body cannot be cleaned by adding anything to the fuel.
The quickie method of cleaning the throttle body is to remove the airbox
boot where it attaches to the throttle body and use an aerosol spray can
of throttle body cleaner while operating the throttle linkage. The right
way of doing it is to remove the throttle body, remove the IAC motor from
the throttle body, clean both parts thoroughly, and reinstall with new
gaskets.

 

Note: My 1996 3.5L Vision TSI has dual throttle bodies. I would assume your
1995 would have the same. I use an old toothbrush, a clean soft rag, and
throttle body cleaner to do this on the vehicle every 20K or so miles. By
doing this, I've never needed to remove these and clean them thoroughly as
Dan has suggested. In your case, you will likely need to remove them
completely if they have not been maintained at all.

I'd also suggest there is a possibility that the timing belt was not
installed correctly and that one or both of the cams may be off a notch.
Have you noticed any loss of acceleration or change in gas mileage? There
are marks on the cams and crank for doing the alignment, but it is easy to
be off one tooth if the mechanic was not very careful.

Good luck and let us know what you discover.

Bob

 

Thanks to everyone! I'll be checking this out and cleaning those throttle
bodies later today (there are two on ours, as well). I'm going to try to
clean them without removal first. I am assuming the timing belt is fine .
. . in my original post, I neglected to mention that as a result of
whatever happened with the tensioner, the belt had jumped three cogs - - -
my mechanis repaired that and we are noticing no increased fuel consumption
and it runs very nice and smooth.) Thanks again! Don

 

Well, I cleaned the throttle bodies using the "quickie method." They
weren't really that dirty. 'A couple of short trips with no trouble (that
was not a change from what was happening before). Now it's been on a
couple of longer trips - - - 10 - 15 miles - - - - it continues to
periodically stop running when stopped at a traffic light. It always
starts right back up and runs smooth. Now, mind you, I'm a little out of
my element here but I did a little testing with my multimeter and my
repair manual this evening. It looks to me like the idle voltage to the
TPS is correct but, upon accellerating, the voltage does not increase.
Here's my question: from where does that voltage come? Is that voltage
supplied directly from the PCM? Also, while doing this test (I
uncerstand, probably just due to its being unplugged) the car did throw a
24 code indicating low or high voltage to the TPS. Thanks again! Don