Misc Calling all "shade-tree mechanics": safe to drive?

[BassMan]

I have a 2000 Toyota Sienna that drives like a dream, about 135K miles. Only issue is that 2 cat converters are dying, so the O2 sensors trip. Won't pass emissions. Emissions testing isn't for a year, so I would like to use it for a year.

Could probably get "Cooter" (think Dukes of Hazard) at the local hispanic exhaust shop to fix it for $2K, but dealer or stricter place wants $4-5K. In any case, repair is about or more than the vehicle value.

Question: I bought a nice Innova SD35a ODBII tester, and reset/cleared the DTC codes. I have not done (or plan on) a full "drive cycle", so the emmissions stuff won't be monitored. Only the "big stuff". In checking with AI, it seems like the 2000 Sienna and codes/standards at the time were designed so even if the "drive cycle" is not done, the true safety issues ARE fully monitored.

Thoughts? Right now, the "Check Engine" light is off (cleared DTC codes), so unless the "drive cycle" happens by accident, in (my) theory, the "Check Engine" light should not come on unless something else breaks. If it comes on, I have the Innova SD35a to check the (non-emissions) codes. https://www.amazon.com/dp/B0F254MVB5?ref=ppx_yo2ov_dt_b_fed_asin_title

 

[tech]

Depending on your jurisdiction, if your drive cycles are not completed you may not pass emissions testing. Drive cycles are determined by run time of certain systems...it doesn't happen "by accident."

Although user feedback varies greatly, you might try one of the "converter cleaner" products.

Just out of curiosity, has anyone actually checked to see if it a downstream O2 sensor issue or if it is failing cats? P0420 and/or P0430 could be caused by either.

BTW - AI lied to you.

 

[BassMan]

Depending on your jurisdiction, if your drive cycles are not completed you may not pass emissions testing. Drive cycles are determined by run time of certain systems...it doesn't happen "by accident."

Although user feedback varies greatly, you might try one of the "converter cleaner" products.

Just out of curiosity, has anyone actually checked to see if it a downstream O2 sensor issue or if it is failing cats? P0420 and/or P0430 could be caused by either.

BTW - AI lied to you.

Nope, did not distinguish between O2 and cat converter. They just went by the code.

Re: AI, my concern is that the "major" codes will still trigger the "Check Engine" light, even if I don't do the formal "drive cycle" so that emissions codes (cat converter and EVAP) are triggered. I'll watch the engine temp, but don't want a fire under the hood or anything nasty. Not worried about emissions testing right now.

Do you have reason to think that codes truly related to safety won't reliably be detected (both pending and confirmed) unless I do the drive-cycle thing?

 

[tech]

Nope, did not distinguish between O2 and cat converter. They just went by the code.

Re: AI, my concern is that the "major" codes will still trigger the "Check Engine" light, even if I don't do the formal "drive cycle" so that emissions codes (cat converter and EVAP) are triggered. I'll watch the engine temp, but don't want a fire under the hood or anything nasty. Not worried about emissions testing right now.

Do you have reason to think that codes truly related to safety won't reliably be detected (both pending and confirmed) unless I do the drive-cycle thing?

"Diagnosing" using codes alone is a good way to throw money away. An example would be both front (upstream) O2 sensors reading excessively lean, while the actual problem could be vacuum leaks, a partially plugged fuel filter or a weak fuel pump. Actually finding the root cause goes far beyond code reading.

Most engine codes (beginning with P) are not related to safety aspects, but more engine operation and emissions systems. ABS and traction control (beginning with C) will light up a different light.

AI isn't up to the task of eliminating false or vague codes, and trusting it for accurate direction is not recommended. At least that's what I've seen...in over 40 years of auto repair.

 

[BassMan]

"Diagnosing" using codes alone is a good way to throw money away. An example would be both front (upstream) O2 sensors reading excessively lean, while the actual problem could be vacuum leaks, a partially plugged fuel filter or a weak fuel pump. Actually finding the root cause goes far beyond code reading.

Most engine codes (beginning with P) are not related to safety aspects, but more engine operation and emissions systems. ABS and traction control (beginning with C) will light up a different light.

AI isn't up to the task of eliminating false or vague codes, and trusting it for accurate direction is not recommended. At least that's what I've seen...in over 40 years of auto repair.

Yes, was looking for that sort of insight! I am not a "car guy". Always go to dealer. Our cars are quite well maintained, though we do pay "dealer prices".

Car is old enough I don't think it worth a proper diagnosis or repair. Parts availability and resale now are a problem (2000 Sienna).

Mainly I wonder if I am "living dangerously" driving it one last year, depending on codes and the "dummy lights" along with my ODB2 reader if I don't do the full drive-cycle correctly. Yesterday, I cleared all the DTC codes, but have not done the full "drive cycle" below. While it looks simple, in practice with the roads here, I would have trouble following the procedure exactly. My understanding is that true safety codes will still trigger (pending or completed), but emissions codes will not trigger unless I succeed with process below.


Day 1

• Cold start
• Idle 2–3 minutes
• Highway cruise 55 mph for 10–15 minutes
• Normal mixed driving
• Park overnight (cold soak)

Day 2

• Start engine
• Drive 45 mph → 25 mph per EVAP pattern
• Verify readiness with scan tool

 

[summerthyme]

Check your oil and coolant levels weekly, watch your engine temps on the dash, and don't sweat it. Engine codes and the various warning l8ghts have very little to do with human safety...they mostly are trying to keep you from blowing the engine up...

Summerthyme

 

[markshere2]

For a year's worth of driving, go get a straight pipe (X2) to replace the CATs.
tell the knuckleheads at the exhaust shop ( midas or the like) to give you the used cats or $100 credit towards the bill.

save your dimes and determine next year if you wanna sink $ into the ride.

 

[Southside]

I will say ANY OLD Toyota with low mileage is worth repairing, as long as the frame/body are sound.
They last forever, and are worth the $ you spend on repairs.
JMHO!
Oh, saw the repair cost. THAT is out of control!

 

[mikeabn]

My Sienna is over 222,000 miles and thank God still going strong.

 

[BassMan]

For a year's worth of driving, go get a straight pipe (X2) to replace the CATs.
tell the knuckleheads at the exhaust shop ( midas or the like) to give you the used cats or $100 credit towards the bill.

save your dimes and determine next year if you wanna sink $ into the ride.

Why bother for a year (other than more HP)? As long as the vehicle doesn't blow-up, catch-fire or leave me stranded, I can live with it throwing codes...
...per a trusted dealer mechanic, the rear bearings and front suspension will need some attention in 1-2 years, but not today.

 

[Old Greek]

Check your oil and coolant levels weekly, watch your engine temps on the dash, and don't sweat it. Engine codes and the various warning l8ghts have very little to do with human safety...they mostly are trying to keep you from blowing the engine up...

Summerthyme

Correct!!
A small piece of black electrical tape will turn off the check engine light for good. I have done it for years. Code read it and make sure its not a safety issue first. Usually sensor crap on emmisions!

 

[Knighttemplar]

I have had good luck using a 90 degree sparkplug defouler on the downstream o2 sensor to get rid of codes on my ford.

 

[BassMan]

I have had good luck using a 90 degree sparkplug defouler on the downstream o2 sensor to get rid of codes on my ford.

So more of a sensor problem, than cat converter?

 

[West]

Strait pipes and good mufflers.

Second the black electrical tape.

 

[BassMan]

Strait pipes and good mufflers.

Second the black electrical tape.

A key constraint is getting it through emissions a year from now.

Right now, it has a history of throwing O2 sensor codes related to the cat converter. I just reset the codes, and finished a drive-cycle for the O2 sensors. Need to finish drive-cycle for EVAP, but have to wait until the gas-tank is less full. Will be interesting to see how fast it throws the codes again.

 

[West]

A key constraint is getting it through emmissions a year from now.

Sell it in Oklahoma.

 

[West]

Sell it in Oklahoma.

Or donate it. And take the deduction.

 

[BassMan]

Or donate it. And take the deduction.

I'd really like to keep it running. Drives like a dream, 140,000 miles, dealer maintained, original owner: 2000 Sienna. Rust is probably OK (body fine), but I need to get under and look soon.

Spent some time learning how crummy the newer cars are (aluminum engine-blocks too small, turbos, direct injection, hybrid electrical issues in some cases), so even if the resale is negligible, the value of reliable transportation and avoiding excess miles on my 2011 RAV4 are important to me.

Even used cars are a challenge. "Cash for Clunkers" trashed the market, along with Covid. Doing all the checks to avoid a lemon (especially service records) is hard. Worse, availability and price on the used cars is bad.

Trying to keep my old cars running for years yet. Sounds like EVs will be better than ICE around 2032 (solid-state batteries), but who know what the overall "climate" will be then.

 

[West]

I'd really like to keep it running. Drives like a dream, 140,000 miles, dealer maintained, original owner: 2000 Sienna. Rust is probably OK (body fine), but I need to get under and look soon.

Spent some time learning how crummy the newer cars are (aluminum engine-blocks too small, turbos, direct injection, hybrid electrical issues in some cases), so even if the resale is negligible, the value of reliable transportation and avoiding excess miles on my 2011 RAV4 are important to me.

Even used cars are a challenge. "Cash for Clunkers" trashed the market, along with Covid. Doing all the checks to avoid a lemon (especially service records) is hard. Worse, availability and price on the used cars is bad.

Trying to keep my old cars running for years yet. Sounds like EVs will be better than ICE around 2032 (solid-state batteries), but who know what the overall "climate" will be then.

To bad you live in a state that requires smog test to beable to register. 26 years old now, isn't a classic now and exempt?

IDK

 

[BassMan]

To bad you live in a state that requires smog test to beable to register. 26 years old now, isn't a classic now and exempt?

IDK

Probably would be able to get historic designation, but done legally, that severely limits regular use...