Can I get a refund for my used vehicle if it fails emission tests?

[TheStatutoryApe]

I purchased a used vehicle. When I bought it the CPU had been reset and I was unable to get it smogged (emissions tested). When the CPU finished its cycles I got it tested and it failed. Mechanic said I should replace the EGR Valve and the 1st O2 sensor. I did so and it failed again. Then they said to clean out the Exhaust Manifold. I did, it was not very dirty, and it failed again.

How probable is it that the CPU, having gone through its cycles with the bad O2 sensor and EGR Valve, is causing the test failures since it is running off bad readings?

 

[edward]

I purchased a used vehicle. When I bought it the CPU had been reset and I was unable to get it smogged (emissions tested). When the CPU finished its cycles I got it tested and it failed. Mechanic said I should replace the EGR Valve and the 1st O2 sensor. I did so and it failed again. Then they said to clean out the Exhaust Manifold. I did, it was not very dirty, and it failed again.

How probable is it that the CPU, having gone through its cycles with the bad O2 sensor and EGR Valve, is causing the test failures since it is running off bad readings?

After replacing any emissions sensors you have to disconnect the battery cables to drop the error codes. Then you have to reconnect the cables and drive the vehicle long enough for the CPU to finish it's cycles again.

Vehicles vary on how long the car must run to complete recycling the CPU. Driving it through a range of speeds usually helps.

Older vehicles do vary. there are some procedures, such as turning the ignition switch on and off at certain intervals clears the error codes. The same ignition switch on and off tactic is used in older cars to get a light on the dash to flash the error codes.

 

[TheStatutoryApe]

Thank you Edward. I was pretty sure that's what I ought to do but did not want to waste money on more trips to the smog check.

 

[madhatter106]

Depending on the age of the vehicle it can be OBDI or OBDII that will also help in determing what information is being read by the ECU to cause the faults and what is being reported to the smog station.

Have they given you a print out of the OBD (on board diagnostics) report? Doing the shotgun approach of R&R random parts is expensive and usually the mark of someone not knowing what they are doing.

resetting the ECU on OBDII vehicles require that the system runs thru a complete hot/cold cycle, this means that the vehicle is run up to operating temperature then driven for 'X' amount of miles then parked over night to cool off to 'cold'.

clearing codes is done with factory or specialty diagnostic eq as hard codes are not reset by a disconnected battery. early systems could be cleared and some 'dumb' late ones can be by shorting the battery leads with the battery removed, this will reset all volatile memory in the car - radio, climate, seats, etc... it's only the soft codes that get cleared with a battery disconnect.

If you're still worried about passing I think NAPA and pep boys will loan out the OBD readers to pull the codes that will help determine what the problem is.

Also some states require the seller be responsible for the vehicle passing emissions before it's title is transferred.

 

[TheStatutoryApe]

Thank you Madhatter.

As I noted in the OP when I purchased the vehicle the CPU had been reset. I had taken it into the test station to see if it would pass smog before I purchased it and they said that they could not test because it had not completed its cycles. I purchased anyway, which may have been a bad idea, and when it completed its cycles it failed smog, specifically the NOX readings were quite high. I took it to Pep Boys and they tested it and told me that the EGR Valve and #1 O2 sensor needed to be replaced. A friend of mine helped me and we did these things on our own. But it failed again.

Pep Boys took another look and the tech said that there was still a problem with the EGR Valve based on their readings except that the valve was obviously new and in working order so there must be blockage in the Exhaust Manifold. Cleaned this at home as well but my friend says that it was not at all blocked up. Failed smog again.

So my working theory is that the data collected and utilized by the CPU from going through its cycles while the EGR Valve and O2 Sensor were bad is causing the emissions controls to act as if those things are still bad and hence the test failures. One of the guys at Pep Boys mentioned that we may want to get the CPU reset though none of their diagnostic reports or techs said anything about doing so so I did not. From the initial issue with the vehicle not being testable and what I read online regarding this issue I am fairly certain that a "soft reset" should work (assuming my theory is correct). After performing the "soft reset" the vehicle did start idling and running differently so I am crossing my fingers and hoping. Otherwise I will have to take it to a muffler shop to see about the Cat.

 

[rhody]

I assume since you said you took it to Pep Boys this is in the US. That being said, I believe that if you keep all your receipts and have exceeded (a limit in dollars) set by the state or possibly federal regulations, then the vehicle passes by default (waiver limit).

It seems like you have spent some decent money on parts, but possibly not on labor, which if you had had the work done by a shop could have put you over the waiver limit. See http://autos.yahoo.com/maintain/repairqa/exhaust_muffler/ques077_0.html" here. Find out what laws apply to your state. You may be surprised and not have to spend a ton of money to bring yur vehicle into compliance. Good luck.

Rhody... :grumpy:

 

[TheStatutoryApe]

Thank You Rhody.

I'm in California. Here there are two options. One is that the state will give you up to $500 to assist with repairs so long as you have applied and qualified and taken the vehicle to a "Gold Shield Station". Under their income eligibility requirements I made just barely more than the maximum last year so I do not qualify. Other than that there is a vehicle retirement program where they will pay you $1,000 if you and your vehicle qualify (more if you qualify as low income). So if I give up on it I may be able to get some of my money back.

 

[BobG]

You may have passed the deadline, but doesn't a seller have to refund your money if the vehicle fails to pass emission tests? In states with emission testing, it's usually illegal to sell a vehicle that can't pass emission tests.

Naturally, there's a limited time period for that to apply (which your private sellers/lower reputation car lots will neglect to tell you about) since car parts could fail/degrade after a while or the buyer could do things to the car, etc. Of course, the problem with that is that many (most?) buyers don't know the laws about emission testing very well and delay having their car tested until the temporary tags are about to expire, which is almost always well beyond the deadline for getting your money back for a failed emission test.

Personally, the fact that the CPU was reset before you bought the car makes the whole transaction look very suspicious, as if the vendor intentionally made it impossible for you to test the vehicle ahead of time. I'm thinking the initial pre-buy test (if you saved the results/receipt) and the initial post-buy test could get you a full refund from the vendor.

I'd check the details of California's emission test laws if I were you.