Chrysler Repair: 91 V-6: codes 21,32,52, vacuum hoses, hesitation problem


Question
QUESTION: I was asking and you were answering , then I couldn`t ask anymore. Do they allow only so many follow up questions?
I had a neighbor do the ignition thing.
This is what he came up with
12  21  32  52  55

ANSWER: Hi Jennifer,
The 12 I described about the battery having at some point been disconnected. If as far as you know that hasn't happened in the past 100 key starts then I would take a look at the battery and check to be sure the clamps are tight on the posts and that the wires are still well attached to the clamps.
The 21 and 52 are both about the same sensor, the heated oxygen sensor and that it isn't apparently functioning. That is an easy replacement (similar to replacing a spark plug) and the cost should be less than $100 for the part and maybe a half hour of labor. It would not likely be the cause of the hesitation and replacing it will reduce pollution and increase the fuel economy.
The 32 code does show that the engine computer detected the egr valve malfunction. I would  simply have the valve stem lubed and moved back and forth at this point and have them simply observe that the stem does move back and forth as they rev the engine as a test of its function. I suspect that will solve your hesitation problem. Also they can examine the vacuum hoses that operate it. But replacing the egr valve is not something I would buy into.
The 55 means end of readout.
Thanks for the ratings and nominations!
Roland
PS Might your neighbor also look for the egr valve and spray the stem?

---------- FOLLOW-UP ----------

QUESTION: I can get my neighbor to spray the EGR valve, someone else said do not use WD 40 but I forget why they said NOT to? Heated oxygen sensor , that needs to be replaced ? What is that ?    I will have the EGR valve only sprayed , but if needed to be replaced is that big money???

ANSWER: Hi Jennifer,
I have had excellent success with WD-40 when the problem is that the valve stem is gummed up with exhaust gas crud. If that doesn't work then the valve can be removed and further cleaned out, and if that doesn't work then it can be replaced. I don't know the cost of the part but you can ask at the dealer parts counter or parts store. I have not experienced any 'downside' to using WD-40. It is not a major job to replace it. But if a squirt of WD-40 AND moving the valve stem back and forth as described frees up the 'action' then why not try that? Simply spraying the valve may not do the trick, but also moving the stem back and forth to spread the WD-40 inside the valve body will probably do the job.
On the heated oxygen sensor is a device that looks like a spark plug that is screwed into the exhaust manifold and is used by the computer to adjust the mixture for optimum efficiency and minimize pollutants. It has a finite life and also it has 4 wires that are very fragile so those can also break and cause failure. It should be easily accessible for replacement. Again, a neighbor can do that if he is willing (the place where the sensor screws into the manifold should be sprayed with WD-40 and let sit for a few hours; care taken to not break wires when installing the new sensor) or you could ask the shop what they charge.
I hope this is helpful. Thanks so much for the latest nomination.
Roland

---------- FOLLOW-UP ----------

QUESTION: If I had to have the EGR value replace din the future, is that expensive ?  If everything is fixed as it it now, I believe I am looking at 3-4 hundred dollars, if I can wait on the EGR valve, how much do you think the  price might go down, also the EGR valve hoses, they can be replace if need be without out replacing the EGR?

Answer
Hi Jennifer,
I don't believe the labor to replace the valve is very much, just a few bolts,
The question is what is the price of the valve (check at parts counter), but chances are either lubricating the stem or removal and cleaning out will do it without replacement. Again, lubricating costs virtually nothing. Replacing the oxygen sensor shouldn't be more than the part and maybe a half hour of labor.
So I don't see 3-4 hundred dollars is likely now, and if that is what the shop is saying now I would try an independent shop for this, not a dealer. It is not something that requires a dealership to do.
The egr hoses are very cheap and slide off and on 'nipple'-type fittings quickly. So don't get 'taken' by the shop about this.
I just checked at Autozone Parts store and the oxygen sensor is about $58, and the egr is $100 for the original equipment replacement type (the best you can buy).
Many thanks for your kind remarks and nominations (3). Five nominations is the 'limit' that will be counted for me.
Roland