Crysler voyager -95 3.3l Backfiring in aircleaner

My Voyager is backfiring in the aircleaner at 3700-4000 rpm when i
drive it and if the gearbox is in park and i rev it up to the above
rpm. It starts to missfire slightly and if i press the gas even more
it will backfire so much that i even blown a aircleaner top off. This
happens almost everyday but sometimes it will run perfektly. I´ve
changed wires and plugs whith no change.
There is no error code in the "check engine lamp" only 55.

Is there someone that can help me, i´m going crazy over this.
I´ve read a lot about mis/backfiring here, but nobody seems to have
exactly the same problem as me. meaning at a specific rpm regardless
of load/uphill/downhill/decelerating/in-gear and so on.

Help please!!!!!!!!

Janne

 

timing ???

 

spark and fuel pressure is not monitored by the pcm to set a fault code, you
may have very well damaged the coil. especially if you kept driving it with
this problem

 

I"d do a coil pack, wires, and plugs.
Larry

 

Does your state have an emissions check? An EGR valve stuck closed
might cause this, and if your car has high NoX emissions that's the EGR.
Sometimes when this valve fails it won't set a code.

Did someone replace the plugs with a set that have the wrong heat
range?

Ted

 

EGR valve will not cause this stuck open or closed

 

Yes we have pretty hard emission checks here in Sweden, almost like in
California i think. We check the car and emissions every year.
I thougt that it may be the lamda some time ago, but the emissions was
perfekt in the test.

 

Sorry, there is no way to set the timing.

 

I have thougt about the fuelfilter before but i don´t think that´s it
because
i can load the car with a big boggie caravan and it works fine in the
range under the 3700rpm whith the gaspedal to the floor. So i tink it
gets all the fuel it want´s.

 

Have them check the emissions again if you can get it done for free - here
in Oregon you can, the state inspection stations will test for free.

Have someone put a scope on the ignition system.

Ted

 

I checked two weeks ago at a friends workshop and it was perfekt,i
checked the timing on the ignition as well.
What i don´t understand is why it starts to mess around at that
specific rpm.

If i slowly goes up to 3700 rpm with gearbox locked in position 2 the
engine will stall and lack power and sligthly miss in the ignition and
while it´s doing that the rpm gauge will go crazy and be all over the
place. If i continue to press on the gaspedal it would miss even more
and in the end start exploding in the air cleaner. If i would go about
55 m/h (90km/h)and try to accelerate so the kickdown engages, it would
shift down and just blow the top of the aircleaner, belive me i tried,
it blow the plastic hinges right off.

Janne S
(By the way,Sweden is a country next to Norway and Denmark)

 

What is the engine size? 3.0?

Ted

 

Crysler voyager -95 (3.3L) Backfiring in aircleaner

Janne

 

Replace the spark plug wires. This is fairly common symptom when they are
defective . At the vehicle's age I'd bet on this being the cause of your
backfiring.

Bob

 

Done that...twice!! and plugs.
First with aftermarket cables,now original wires and new plugs for
about 40$(295SEK) a piece. Not cheap but will stay in the car for the
next 3-4 years and thats nice.We all know how much fun it is to cange
plugs on this car ;-)

 

Does any Chrysler mechanic out there know if somthing special happens
in that rpm range (3700-4000rpm). If extra fuel is added or if
ignition timing is radically changed or something like that????.
Could the problem be a faulty computer unit??.
And why does it sometime work perfectly, it has nothing to do with
weather conditions dry/wet/hot or cold.


Janne S