Chrysler Grand Voyager 2003 3.3 - error code p0420 and whining

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Wed 20 Jul 2011 16:31
Chrysler Grand Voyager 2003 3.3 - error code p0420 and whining - bradleigh1977

When i got my 3.3 2003 limited xs it has a whining, which got higher the faster then engine revved--but it didn't really bother me--but got the engine management light on today--and got the code p0420--

now done some searching and its to do with emmision or fumes or cat etc...now i have also found this.....

Had the same problem took forever to find where the whinning was coming from. Look under the middle of the car while running and listen for a whine while someone else eccelrates it. There is a plastic 3 ball looking thing that has a vacumm in it that helps with pressure. Mine was shrunken from heat and therefore leaked its called a Vac Harness and it was 8.00 from the dealer. part # was 4431325 hope this helps good luck.

Im no expert but they could be linked? any one else have any ideas?

my car has done 180000 miles and has a full service history up to 160 ish thousand miles.


If its the cat, where is the sensor for ir on my car? - as the "heat sheild" on the top of my manifold where it meets the egine has all burnt/rusted off...is the cat sensor in there or further along the pipe---if its no where near i'm sorry!!

And whats the likely hood of me swapping the 02 sensors? are they hard or easy?.

Edited by bradleigh1977 on 20/07/2011 at 16:46

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Fri 22 Jul 2011 11:11
Chrysler Grand Voyager 2003 3.3 - error code p0420 and whining - Laurance

check for exhaust leaks at the manifold, pipes, catalytic converter. Repair as required. Use a scope to diagnose the oxygen sensor operation (Tip: The oxygen sensor in front of the catalytic converter normally has a fluctuating waveform. The waveform of the sensor behind the converter should be more steady). Inspect the downstream heated oxygen sensor (HO2), replace if necessary Replace the catalytic converter One thing to note is that many vehicle manufacturers offer a longer warranty on emissions-related parts. So if you have a newer car but it's out of it's bumper-to-bumper warranty, there still may be warranty on this type of problem. Many manufacturers give a five year, unlimited mileage warranty on these items. It's worth checking into.

Edited by Laurance on 22/07/2011 at 11:11

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