[The05SIENNA]

A few months ago, I got the thing to run after three years of sitting by replacing the front manifold/cat converter, and doing a few other things. Moved it out of the shop (didn't really want to, but had no choice), but it doesn't stay alive for long. Finally got a code reader, and now can do some diagnostics on it. I can't read live data because my reader doesn't do that, and the engine won't stay alive for long at all anyway.

Seeing that the misfires are specific to bank 1's cylinders, it would be easy to assume that the bank 1 cat is also clogged. Makes sense, and that'll be the first thing I check. If its clogged, hopefully replacing that will clear up the misfires, and I can tackle the other codes next.

P0018 bothers me. The timing belt was replaced about a year before it broke down, so I would be shocked if it is worn already. Could it have slipped timing somehow? I personally, never touched the timing components.

P0051 is odd, the O2 sensor is new... Both P0018 and P0051 are problems in bank 2, so I am guessing they're not directly related to Bank 1's issues.

Been concerned about what caused the cat(s) to clog. I may have found a cause. There is a significant amount of oil that builds up in the throttle body whenever I start it a few times. Pulled the PCV valve (first suspect) and did the "shake and hear it rattle test". It rattled. This doesn't necessarily mean it is good, but its a good start. What else in the PCV system could do this? I've read cylinder blowby could cause this as well, so I could do a compression test I guess, wouldn't hurt to try that anyway. Worst case scenario, we have to rebuild it, which was the initial plan anyway!

I was advised to check fuel pressure in my first post. Not a bad idea, and I'm still willing to do it. At this point though, I'm not sure this is my big issue. Perhaps do compression test first? What do you guys think?

Looking for anyone's two cents and experience here, the thing has been used hard and possibly not maintained in the best way? Not sure, I was a child for most of its service, so I don't remember at what intervals it got oil changes and such. It used to be a daily driver, but it is comforting that these engines are pretty resilient.

 

[paul r]

Remove the engine beauty cover , have some one start the engine. Do you smell gasoline especially in the area of the fuel pressure dampener on the
fuel rail? Just a thought!

 

[The05SIENNA]

Remove the engine beauty cover , have some one start the engine. Do you smell gasoline especially in the area of the fuel pressure dampener on the
fuel rail? Just a thought!

I've never smelled gasoline in the engine area, but I've also never had someone else start the engine for me. I'll give it a shot!

I forgot to mention that I removed sensor A on the bank 1 manifold, and that seemed to help it run better.

 

[paul r]

I mentioned the fuel dampener as a member here had multiple issues like you do and it turned out to be a faulty FPR ( fuel pressure regulator) unit. So at least you can eliminate that.

 

[cougarhound]

Looks like your crankshaft position sensor is bad which causing random misfires because the coil on plug system needs the crankshaft position sensor to fire properly....Just a guess. Fix your timing issues first.

 

[sixto]

Any chance rodents took residence in the engine bay while the van was out of service? Crank sensors typically fail from heat cycling, not sitting idle.

Sixto
‘04 LE FWD 206K miles

 

[The05SIENNA]

Definitely a very strong chance the rodents could've gotten in there, but I don't see any signs of them living there. Doesn't mean they didn't do damage though. Are you suggesting that rodents possibly chewed up the CKP connector wiring? I'll have to check that.

 

[cougarhound]

Definitely a very strong chance the rodents could've gotten in there, but I don't see any signs of them living there. Doesn't mean they didn't do damage though. Are you suggesting that rodents possibly chewed up the CKP connector wiring? I'll have to check that.

You can prob test it with a multimeter. It's better to test it than replace it with random crappy aftermarket parts. That could make things more difficult to troubleshoot. Especially with electronics stuff. Best to go OEM.

Like I replaced an O2 sensor with a Bosch one and it was still giving me faults. I was chasing my tail for a while until I replaced it with a Denso sensor.

 

[The05SIENNA]

You can prob test it with a multimeter. It's better to test it than replace it with random crappy AutoZone quality parts. That could make things more difficult to troubleshoot. Especially with electronics stuff. Best to go OEM.

Great advice, will do! Thanks for the video!

Wouldn't a CKP voltage/circuit problem throw its own code? I've seen CKP Circuit codes before, but not on this vehicle. P0018, being a correlation issue worries me. I had something similar on our Accord, and replacing sensors (OEM) did nothing at all. Probably a timing chain stretch, car was given to us with the issue. I'm worried something similar could be happening here with the belt, but it is best to start with the simple.

Could a slightly out-of-time engine cause damage to the cat(s)? If the combustion process and efficiency is altered, could cause it incomplete burning and/or overheating of the converter? I don't want the vehicle to be driven until I find what happened to the catalytic converters or it'll happen again. My suspect is the oil in the throttle body atm.

 

[cougarhound]

Great advice, will do! Thanks for the video!

Wouldn't a CKP voltage/circuit problem throw its own code? I've seen CKP Circuit codes before, but not on this vehicle. P0018, being a correlation issue worries me. I had something similar on our Accord, and replacing sensors (OEM) did nothing at all. Probably a timing chain stretch, car was given to us with the issue. I'm worried something similar could be happening here with the belt, but it is best to start with the simple.

Could a slightly out-of-time engine cause damage to the cat(s)? If the combustion process and efficiency is altered, could cause it incomplete burning and/or overheating of the converter? I don't want the vehicle to be driven until I find what happened to the catalytic converters or it'll happen again. My suspect is the oil in the throttle body atm.

I don't know about the cats. I do know that they are finicky and that you can't rely on the cat fault codes if your engine is not running right.

 

[The05SIENNA]

I don't know about the cats. I do know that they are finicky and that you can't rely on the cat fault codes if your engine is not running right.

Will the ECU run using default information if I unplugged the Crank Position Sensor, or is it required for starting the engine? Probably would not help to do this anyway, just thinking and typing... Definitely will be testing with multimeter when I can!

Also, is it possible that there is an issue with the cam sensor(s) instead of crank, since it is a correlation issue between the two?

 

[sixto]

Probably won’t start without a crank sensor but might not throw a crank sensor code either.

Sixto
‘04 LE FWD 206K miles

 

[cougarhound]

Will the ECU run using default information if I unplugged the Crank Position Sensor, or is it required for starting the engine? Probably would not help to do this anyway, just thinking and typing... Definitely will be testing with multimeter when I can!

Also, is it possible that there is an issue with the cam sensor(s) instead of crank, since it is a correlation issue between the two?

No I don't think it would start. I would I unplug the crank sensor and do a visual check for any corrosion. If you can't get a multimeter, then just swap it out. It's not that expensive. These engines are pretty bullet proof so I doubt it is anything mechanical.

 

[cougarhound]

Also I don't think a stretched timing belt or bad camshaft position sensor would prevent an engine from starting. It will run like crap though.

 

[circus]

I was advised to check fuel pressure in my first post. Not a bad idea, and I'm still willing to do it. At this point though, I'm not sure this is my big issue. Perhaps do compression test first? What do you guys think?

For heaven sake check the fuel pressure. First thing to check, not last. Very common problem on all vehicles that don't start, hard to start or runs like crap.

 

[paul r]

Check the Oil control valve screens. Need a 14mm socket/wrench and a needle nose pliers.

 

[Roader]

A few months ago, I got the thing to run after three years of sitting by replacing the front manifold/cat converter, and doing a few other things. Moved it out of the shop (didn't really want to, but had no choice), but it doesn't stay alive for long.

I vaguely remember the original post. Is all the three-year-old gas gone? Is the engine now only ingesting nice, fresh fuel? Watery stale fuel could account for most of those codes. And the crankshaft vs. cam timing problem could simply be the case of old, congealed oil in the VVT actuator. That engine needs to start and run and heat up to operating temp.

 

[grateful908]

I vaguely remember the original post. Is all the three-year-old gas gone? Is the engine now only ingesting nice, fresh fuel? Watery stale fuel could account for most of those codes. And the crankshaft vs. cam timing problem could simply be the case of old, congealed oil in the VVT actuator. That engine needs to start and run and heat up to operating temp.

That was going to be my thought, Also... I would run it without the cats and take it out on the highway.., 3 years is a lot of cobwebs to get rid of..

 

[cougarhound]

I hear some people using starting fluid but that's kinda scary for me. Lol

 

[Roader]

That was going to be my thought, Also... I would run it without the cats and take it out on the highway.., 3 years is a lot of cobwebs to get rid of..

My neighborhood went though a spat of cat con thefts a couple of months ago and it was pretty common to hear an unmuffled car. I think running it w/o the cats is a splendid idea, and it wouldn't hurt a thing.