Chrysler Dynasty AGAIN......Mr Stern, HELP!

Sounds like a bad coil.

Ted

Start with having the fuel pressure checked, sounds as if there isn't enough pressure and that's why it is backfiring thru the throttle body. If the check engine lite is on when you drive it (which I doubt it) what is the code.

Glenn Beasley Chrysler Tech

The check engine light DID come on when the neighbor pulled the oxygen sensor ?? off.

Could it be this sensor or the relay that it is connected to? PS..My hubby is a chef so make this as painless as possible.

Fuel pump is new maybe 2 yrs (max) ago. And neighbor says the car IS getting fuel. We thought fuel filter but when this relay switch (to oxygen sensor) was removed the check engine light came on the the idle rpm went up. ??

One more thing... Why does it run normally when it's cold, but after 10-15 min of driving, that's when it starts to act up?

May I just say....this is a WONDERFUL resource, and I'm sure glad I came upon this site.

Sounds like time for a new O2 sensor to me. When you unplug it the computer goes into a default mode and it sounds like the computer is getting wildly inaccurate readings from the O2 sensor (i.e. it sounds like the sensor is reading way richer or leaner than the actual A/F ratio)

it's easy enough to try, ASSuming that it isn't seized in place.

nate

What engine does this car have? It could be the 2.5 4 Cyl, or either the 3.0 or 3.3 V6. Have you tried to dump out the codes using the key off/on method?

If it is the 3.3, the crank and camshaft sensors should be checked along with the other suggestions that have been made.

-Kirk Matheson

To check the computer codes:

With the engine off, switch the ignition key on-off-on-off-on, leaving it "ON". Do not go to "start", just "on" during this procedure.

Watch the "Check Engine" or "Power Loss" light. It will turn on, then go off, then will begin to flash-out any trouble codes that have been stored. For instance, if it flashes:

flash flash flash

flash flash flash flash flash flash flash flash

flash flash flash flash flash flash flash flash flash flash

Then you have a 12 (one flash followed by two) a 35 (three and five) and a

55 (five and five). 55 means "end of codes" or, if by itself, "No codes stored. Check the codes and report what you find.

Sounds like an O2 sensor to me as well. O2 sensors do NOT affect the fuel mix when the engine is cold. When the engine heats up, then it provides a signal to the engine control module. If the signal the ECM gets is not correct, then all kinds of crap can happen.

My mini-van used to cough and sputter going up hills. But when I checked, no engine fault codes! But it did not do this all the time. :(

After a couple of months I took it to my usual shop. They diagnosed it with a scope as the O2 sensor within 2 minutes. In & Out of the shop in 30 minutes - including paying for the repair.

hth

An 02 sensor wont cause that problem, more then likely the map sensor or coolant temp sensor is out of calibration. If those sensors are out of calibration it may not set a fault code but will cause the engine to run bad. The coolant temp sensor acts like a choke when the engine is cold, it allows the injectors to stay open longer to compensate for the cold temp. when the engine warms up the coolant sensor is supposed to see this and reduce the amount of time the injectors stay open thus causing a leaner mixture. If the engine warms up and the coolant sensor doesn't see this it is going to cause a really rich mixture .Do you see black smoke out the tail pipe when this happens?

You will probably need to have a scan tool connected so that the sensor values can be monitored when the problem is happening. And just because you had the fuel pump replaced 2 years ago means nothing (especially if its an aftermarket pump) Your neighbor says its getting fuel...we know that because it runs a little bit.....if you don't have the proper fuel pressure it will cause this to happen. Bottom line, perform fuel pressure test and if ok, scan the system while the problem is occurring.

Glenn Beasley Chrysler Tech

Thank You Kirk....yes, it is the 3.3. Sensors huh? Will try the rest and get back.

OKAY SO I DID THE ON OFF THING AND I ENDED UP WITH 3,2,5,3 OR 32 AND 53 I AM NOT SURE CAN SOME ONE HELP WITH THIS PLEASE,,,TY

Don't just replace parts because there is a fault code. Especially since you said your neighbor had disconnected some sensors, because if he did that with the key on....codes would have been set, especially the EGR Valve. Since someone has already been disconnecting things the first this to do is clear the codes and se if any pop back up Glenn Beasley Chrysler Tech

OK, that's possible. 32 indicates an EGR system fault that could easily and totally account for your car's poor running. Most likely a faulty EGR valve, but could be another component in the system.

53 would indicate an internal fault in the engine control computer, which is not very common but if it is real, it could also be causing or contributing to your problem. Be sure to check the codes really carefully and make certain you get the "grouping" right. You really have to watch the length of the pauses between flashes, otherwise you can confuse a 24 for a 51 or a 33, etc.

What engine does this car have?

ok....so we replaced the O2 Sensor, and it seems to idle nicely (even warmed) BUT...as soon as you depress gas pedal, once again, it starts to putter and peter out. Did the on/off thing again, and THIS time we got....12, 14, 55 Absolutely positively. SO??? Fuel Filter? By the way...where will we find the EGR valve? We are looking at a Chilton Caravan Town and Country book and according to diagram...it's not there? Different car...different location?

Thank you sooooooo much, in case I haven't mentioned it before. (Too bad fixin' cars was as easy as cookin') :(

funny you should mention SIEZING IN PLACE. We went to a Pick n Pull wrecker to see if we could pull one off a recent wreck. NOPE NOPE! After an hour and many scratches and punctures, we gave up and bought a new one. Installed it no problem, and now it idles a bit better but only until you depress gas pedal and then it sputters again! Oh well. Enough for today....Tomorrow...New fuel filter. After that... CLIFF?

12 just means that the battery's been disconnected recently. 14 refers to the MAP sensor.

55 merely means the end of the stored codes.

Ken