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2001 P3191 Troubles, 12V Battery related?

Discussion in 'Generation 1 Prius Discussion' started by Scott127, Oct 19, 2023.

  1. Scott127

    Scott127 New Member

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    OK, I've been reading other posts for a while about P3191 and have tried quite a few things, but no posts that I have read quite match my situation, so here it goes:

    I bought this 4-door sedan 2001 Prius with about 119K miles, that had a blown head gasket. Had no belt at the time, and was a steal for $1200 so I decided it would be fun to fix on. Almost flawless interior and exterior so, why not? Put the belt on right away. She's running great. I use some head gasket sealant with some coolant (which was pretty dry, hence the overheating), and this worked like a charm - tailpipe smoke cleared right up. She is still up and running fine, with no problems, better than ever. I didn't exactly bleed the coolant system, but I figured no need to yet. It is definitely on my list to-do.

    Next thing to fix was the MFD, which was just yellow and showing nothing, although it would light up... so I bought one on the internet and swapped it out (I didn't program anything, as I don't think I need to, as I saw in a video this guy did not). The plastic that held it in place, which was the only interior damage and had a crack, totally shattered when I went to take it out. So I had to wait a few more weeks on one of those to come in the mail. During this time, she was not running, just because the dash was all opened up and the MFD was waiting for the new dash part to be installed. I decided to change the oil during this period of time (to get rid of that yucky brown chocolate milk coolant/oil). I swap the oil filter out while I'm at it. Which was the most stuck filter I had ever seen, man! But I managed to get it out.

    Now the plot thickens. I finally try to fire her up after the MFD swap/oil change. But the battery had died. Uh oh. I think the owner told me the battery was on it's way out, that she had to jump start it or something (she was not a mechanical expert)... but she did contact the person she bought it from, and they said that they had replaced the hybrid battery pack already. Anyways, so I'm now able to start the car when I jump it, but not otherwise. The battery is not holding a charge. Every time I want it to start, I have to jump it again (I start using the emergency jump start battery thing). So there are two problems here 1) the 12V battery not working, and 2) the P3191 code.

    I will go step-by-step through my interventions:

    A) When it is fired up, it does the triangle of death thing and gives me a P3191 code. Engine sounds fine, in regards to the idle is not rough or anything, but then does the automatic shut off thing after about 8 seconds or so, as many people report. At first, I think maybe it's out of fuel. It was low. So I fill it with 5 gallons or so using a gas tank. But the new gasoline does not register. No changes in behavior.

    B) I had noticed earlier that it took less oil then it said it would online. It says only almost 4 quarts, but I had just filled it until the dipstick read good. I thought... maybe it is not registering enough oil for some reason, as I read online that there's an oil weight sensor or something that can throw the P3191 code. So I fill it to the measurements I am reading online and it is over the dipstick amount. Probably not a good idea, as I think I might have caused a new problem. No changes. So I drain some of the oil out, and now it's right at the top bead on the dipstick.

    C) Next, I clean the throttle body out, which had some build up but wasn't terribly bad. That managed to make the gasoline register! Which I think is significant, but it still won't stay on past 8 seconds, still gives me the triangle of death. It blinks as if there's nothing for 3-5 seconds or so, but then comes in with a full tank, before it shuts down the engine again. So that tells me that when the battery died, it reset the throttle calculation, and that was definitely halting the engine from starting. Oh, and also, when I let it stay on as long as possible, trying to pull the codes before it dies from no 12V battery functioning, the PS light goes on briefly near the end, right before it dies. Maybe that's related? Or something else? Still not letting the gas engine start.

    But I should mention that in the process of taking off the intake, I notice above where the belt had been ripped off, it appeared to have melted/ripped through some of the flanges on this tube. Which was a pain in the butt because I had to get the headlamp loose and even the front passenger fender, but I bought a new one and put it in. I think this could be related to how it overheated? I don't know, but it was broke, so I replaced it. Here is the name of the kind of part I replaced: Toyota Prius W2 1.5 H 2007 RHD Air Intake Tube Pipe GF491-02670 15489782 (looks exactly the same as the Gen 1 part)

    But basically, once I put this part in, and the throttle body is cleaned, I see a little progress in that the gas is now registering... but still getting my P3191 code, still getting triangle of death and stopping after 8 seconds. And yeah, that PS light comes on for a second or so right before it dies... not every time, but I've seen it twice.

    D) I clean out the MAF sensor with some cleaner, as I figured maybe in the process of removing the air filter to clean the throttle body, that I dirtied something up. The filter looks pretty clean by the way, but it does have some slight tears on some of the flanges. I just left it in there, since that's how it was when it was starting, I figured that can't be the problem. MAF sensor is clean, still nothing changes. This whole time I am having to use my emergency starter battery pack to get the car started again, which will work for a few tries before it dies again and I have to re-connect it.

    E) I brought the battery to O'Reilly's a couple times during this process - they said it is fine and charged it up. It did seem to be holding a decent charge, in that the emergency battery jumper kit thing no longer goes down from 100% anymore... at first it would go down a few percents trying to charge the battery. But for some reason I still have to use this emergency battery jumper. If I just connect the battery and try to use the key, there's no reaction. Just black all over the dash lights.

    F) I'm in Hawaii, the Big Island, on the rainy side, and so corrosion is a definite issue. A friend of a friend is an ex-Toyota dealership person and they said they bet it's the hybrid battery, but won't really listen to all the details I want to give them. Then this guy at O'Reilly's the second time says every time he goes on vacation for a couple months he has to open up the hybrid battery and treat it for corrosion to get it started again, and that he has owned 5 Prius's (Prii?). So, I get it in my head this must be the problem and I open her up last Saturday, measure every module/cell (they are between 6.5 and 7 volts each), use the wire brush on all the terminals and bus linkages, along with electronics cleaner on them and the nuts, and then a light coating of dialectic grease on the buses, nuts, and the terminals. Frightened myself because then it threw a couple more codes, P3030 and P3077, when I tried to start it up. Apparently, I left the battery fan unplugged. Hopefully this will take care of both codes and I didn't mess anything up - I'll try to fire it up again tomorrow.

    G) But today I was thinking, can it just be a bad 12V battery? This battery is not giving me a good reading when I use my voltmeter. It still won't do anything when it is connected, I'm only able to try and fire it when I am using the emergency jumper battery, connected to it via the red/black prongs. I took it to the Toyota dealership and they won't even test it when it isn't connected to my car (I don't trust the O'Reilly's, since they don't even sell these batteries). I could tow my car there and have them try it... or just shell out $400 for a new battery (they have to ship them to the island by boat apparently, everyone else is saying they are cheap).

    My next steps/ideas:

    a) try and clean out any excess oil that may have gone into the engine. I read somewhere that if it is overfilled, sometimes it needs to be cleaned out. I tried to understand where to access this but I can't really find any videos.

    b) figure out if this battery is really dead, by checking for fuses or something? And if so, replace it. I'm thinking that if the emergency battery jumper works when connected to it, though, that possibly this means the battery system is functioning? Oh yeah, I did clean those battery terminals off, and the connections, with electronics cleaner.

    c) clean that MAF sensor again. I watched a video and thought, maybe I could do a more thorough job. But when I did take it off, I didn't see any difference. Nothing looked dirty, nothing appeared any cleaner. But I figured I could spray that stuff way up in there again, just to be safe.

    d) of course, I want to top off the coolant and bleed it properly. I think I can leave that sealant stuff in there... they say you can. I used only a quarter of the bottle, a very small amount. But I could change it out. Either way, I figured I would take it to the dealership for this, once I had it running.

    Any ideas? PLEASE HELP! I've put so much energy into this baby already, I don't want to get burned out on it. I would really like to have it running soon, so I could either flip it and reap a little benefit for my troubles, or let my son drive it to school, who is getting his license very soon. But it definitely needs to be working reliably if I am to do that... Thank you in advance (or as they say here: Mahalo nui loa!)
     
    #1 Scott127, Oct 19, 2023
    Last edited: Oct 19, 2023
  2. Pablo.nyc

    Pablo.nyc New Member

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    Try to start it and immediately shift to N and see if that changes anything.

    The car is doing charge test on startup. If it fails it throws multiple codes after couple seconds and kills the gasoline engine.
     
  3. Trombone

    Trombone Member

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    Excess engine oil will pool in the throttle body (I think that's the correct ID); if you look down below the MAF sensor, you can see it where the pipe bends toward the engine. By holding the butterfly valve open you can get a rag down in there (tied to a stick) and soak it up. Long cotton swabs (drug store) will also work.

    Get a new 12 volt battery, but don't pay dealer prices! I'm using a lawn tractor battery (this one: https://www.batteriesplus.com/productdetails/battery/lawn-tractor-and-mower/sliu1rxhd) with conversion terminal posts (https://www.batterymart.com/p-dek-02033-flag-to-post-terminal-adapter.html). I had previously converted the battery clamps to SAE size. Some have reported success by bolting the existing clamps directly to the battery terminal lugs.
     
  4. ronlewis

    ronlewis Active Member

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    One
    1. Get a service manual or subscribe to the online version, then follow the diagnostic procedures rather than scatter shooting the way you're doing.
    2. What are you reading codes with? Most readers can't be trusted to capture all the codes with these cars.
    3. The 12v fires up the hybrid and the hybrid fires up the inverter first, then about 8 seconds later, the inverter tries to start the ICE. If it doesn't start, you get the 3191. That's kinda all the 3191 tells you - that the ICE didn't start. It doesn't tell you why, and like all ICEs, a non-start can be caused by several different things related to air, spark, fuel or compression. If you're not getting any other codes from a good reader, it is likely not anything to do with spark - that's all pretty well monitored by sensors.
    4. Except, if you have a bad sensor. If your code reader can monitor live data, you can confirm the sensor functionality. I've never had to do that on my Prii, but on my truck, I check the temp-based sensors - EOT, ECT, and MAF - after the truck sits overnight and with key on/engine off (KOEO).. In a stone cold car, they should all be the same and approximately equal to the outside temp. My trucks also have pressure-based sensors - MAP, EBP, and BARO. Again, on a cold engine, they should all be approximately the same and equal to BARO. At sea level, BARO is around 14.7. You can also check sensors by back probing the sensor connectors to confirm they have the right voltage readings.
    5. The usual culprits on a non-start ICE are injectors, plugs/coils, throttle body and MAF. If you're not getting misfire codes, I would wonder whether it's something worse. The ICE on these cars is the legendary Toyota 1.5. They're almost indestructible. I drove one of my Prii for several years before deciding to change the oil before a long trip. Including filter, I only drained 3/4 of a quart. Amazing that it even runs, but that was many miles ago and still no problem.

    Yet, you say it has a blown head gasket, which likely means it ran hot for a long time. Not quite sure how to do a compression check on these cars. You might need the Toyota software to do a relative compression test. However, one sign of a blown head gasket is too much oil - the gasket blows and allows either fuel or coolant into the cylinder. It blows out the exhaust if the car is running, but just sitting there, it can seep past the piston rings into the crank case. Did you smell fuel in the oil when you changed it? I've never trusted miracle-in-a-bottle products, at best they delay worse problems for a little while, IMHO. Gasket can't be that hard to replace, or used ICEs are cheap - I've thrown away several that had no problem at all.

    6. A bad 12v battery can cause several odd issues. Rather than the pocket jump starter, get any good 12v and hook up the positive terminals to your battery with cables. You can connect the negative terminals as well, but IIRC, it's best to ground the jump battery separately. The lawn tractor batteries I buy are $30 at Walmart - look for the U1R so the terminals are in the right position. However, that doesn't have the round terminal, it has flat terminals with a hole. Just pull the plastic insert out of your car's terminals, spread the terminal clamp slight to squeeze the flat terminal inside it, and use the original bolt and nut through the same holes on the clamp and through the flat terminal's hole. Works perfect, nothing else to buy, and Walmart is good about honoring the warranty. Versus the Toyota battery, you can buy13 of the WM battery. If your car has had the clamps replaced with the newer ones to match the newer Toyota batteries, it still works, but no plastic inserts to remove.

    7. As Trombone tooted, you can shift into N once the inverter starts but before the 8 seconds to remove all stress on the ICE. That will often get the ICE to start and idle, but usually the original issue is still there, so it probably runs rough.

    8. Honestly, with a blown head gasket, $1200 isn't a steal, but you can still get your money back, at least state-side, by selling the HV battery and recycling the cat. Not sure what the market is for HV batteries in but no one probably wants to pay shipping to get it back to the mainland.

    Disclaimer: I'm not a tech and can't explain why a lot of things work/don't work. But, I've had almost 20 of these cars since my first '01 and have encountered a lot of different issues. I may be misstating some of this info.
     
  5. Trombone

    Trombone Member

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    Thanks, but it was Pablo.nyc, not I, who posted about the N shift!

    BTW, it takes my '02 about one second or less from key "Start" to engine fire-up, in above freezing temp. Early in the history of the Classic, there was a recall on the ECU because it was programmed to set a code if the ICE didn't start within about 1-2 seconds; below freezing, it sometimes took longer to start, which the original ECU didn't like (Mmm, don't they have cold weather in Japan?), then you'd get the CEL and the code and I can't remember now what-all, but it was a minor PITA. The replacement ECU fixed that problem.

    Ron, it appears that you got the better deal on the lawn tractor battery. It seems that both the Walmart and the Duracell LT batteries are made "right in my backyard," so to speak, by East Penn Manufacturing in Berks County, PA, the next county west of Lehigh County, where I live (Allentown). They have a sprawling facility along the Topton-Fleetwood Road, amidst the fertile Mennonite farm country. Yours is rated at 230 CCA and the Duracell @ 350 CCA, which may account for the price difference. Either one is a better buy than Dealers!
     
  6. ronlewis

    ronlewis Active Member

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    Yeah, the WM batteries are cheap, but they've worked for me. I get at least the 6 months of warranty, but you can actually take them in at 5 months and get another one, lol. And my cars start the ICE within a few seconds too. Wasn't sure if he was timing that or how long it took to stall when it wouldn't start and wanted him to know that there was a delay.

    I still would be worried about the OP's blown head gasket. That just doesn't happen to these ICEs without major abuse.
     
  7. Trombone

    Trombone Member

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    Yeah, these little 1.5 L mills are amazing! Mine is just chugging along with 159K + miles on it; it's on only its second set of spark plugs. Since almost new, it's been fed only "synthetic" oil (Castrol Syntec 5W30) with new Denso filter at every oil change (7.5K mile intervals, by the book); I do my own oil changes. That, plus a clean air intake filter once in a while, and it's happy. I have cleaned the MAF sensor once, using the proper stuff. And that's about it.
     
  8. ronlewis

    ronlewis Active Member

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    Oil change...reminds me that I wanted to tell Scott how to get the stuck filter off. I've had that problem on these cars before. The quickest way, after you've drained the oil and tried to remove the filter with the different types of wrenches made for that, is to just take a longish screwdriver and with a hammer drive it through the filter like a nail, making sure it's through the lower half to not contact the threads on the engine. That provides a "handle" to turn the filter. The screwdriver will probably widen the original hole a little bit, but it'll finally create enough resistance to turn the threads. This works on most filters, btw. Have a pan underneath to catch the oil out of the hole you created.
     
  9. Trombone

    Trombone Member

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    I’ve been using one of those filter cap gizmos, the kind that fits on the top of the filter, and has a 3/8” hole to accommodate a socket wrench. Works like a charm, and less messy than the screwdriver method.
     
  10. ronlewis

    ronlewis Active Member

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    Of course, that's why I said to try those first. But I've had one of these that wouldn't come all that way. The screwdriver hack is easy, quick, but just a little messy.
     
  11. Trombone

    Trombone Member

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    The filter cap-type removers are very filter-specific. There is only one size, and I mean "only," that fits the Denso filter I use. Specifically, for the Denso/Toyota 90915-YZZN1 filter, the OEMTOOLS 25404 is a perfect fit (whereas the 25405 is not---duh!). I bought the filter cap at AutoZone, IIRC, but it's not listed on their site now.
     
    #10 Trombone, Oct 28, 2023
    Last edited: Oct 28, 2023
  12. ronlewis

    ronlewis Active Member

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    Everyone owns a screwdriver, lol. Gen1 owners have to be frugal to keep these cars on the road. Of course, you can drive your screwdriver through the bottom first to create a drain hole and not make a mess at all. But I'm usually gonna wash my hands anyway, so I go for it.

    Of course, the best advice to folks is to quit tightening your filters on so hard. It's the rubber gasket that seals, not the pressure. A good hand-tighten is sufficient. You shouldn't need a tool at all.