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2002 Prius - CEL on. Suggestions?

Discussion in 'Generation 1 Prius Discussion' started by lvsteve, Aug 1, 2013.

  1. lvsteve

    lvsteve Junior Member

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    I have owned a 2002 Prius (now at 115K) for just over a year now.

    Ironically the warranty I paid too much for when I bought it expired just days ago, and now everything's gone haywire. :p Red Triangle of Death etc. Car would turn on, run for a second, and then shudder to a stop. I was getting the turtle light quite often around that time, but I was hoping it was just the heat (I live in the desert - the day I got the triangle was just a tick under 120 degrees).

    I believe the codes I got were P3100 and P3109 (but I'd have to check again to make sure I'm not making this up). Dealership said I needed a new tank and fuel pump assy, throttle cleaning, top end cleaning and spark plugs and they wanted $1700 for parts and labor.

    Rather than go that route I had the tank/pump assembly ordered, had it replaced by a mechanic friend, everything ran just fine for a couple weeks.

    Last night driving home from work I stopped for a bit to chat with a friend, car idled in the heat (probably 112 this time) for about 45 minutes, and then when I resumed driving I got a yellow triangle and a CEL. The display showed a battery symbol, but that went away within 2 minutes or so and was replaced by the exclamation point/car symbol.

    I parked it overnight to see if letting it cool off would help. When I started it this morning the yellow triangle was still lit. I tried to back out but my power steering wasn't working and I suddenly had a "PS" light on the display. I turned it off, restarted it, and the light is still on but this time I had power steering and no issues. Managed to make it to work.

    There's a couple things I have in mind: the oil is a little overfilled, I haven't cleaned the throttle body, and I didn't change the spark plugs.

    Any chance cleaning the throttle body, draining the oil, and spark plugs might get me rolling reliably? This has been the best car I've ever owned, I'd love to keep it rolling.

    I should note that (possibly due to the desert and the Max A/C running at all times) I really only get about 35 mpg in the city unless I'm really driving conservatively. Does this seem really low?

    Thanks SO much to anyone who can lend me any advice.

    -Steve
     
  2. bwilson4web

    bwilson4web BMW i3 and Model 3

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    Steve,

    We really need to see the codes from a Prius-aware scanner. This includes any "information" or sub-codes that further refine what is going on. But one item aside, heat is the enemy.

    Your climate means this older Prius is especially challenged. At a minimum, try to park in the shade, don't let the sun further exacerbate the problem dealing with the heat.

    Bob Wilson
     
  3. lvsteve

    lvsteve Junior Member

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    Thanks so much for your reply. My little cheap scanner clearly isn't cutting it but my mechanic friend has a hefty laptop sized monster (Maxidas, I believe?) that will, hopefully, do the trick. If he's free I'll scan it today and post back shortly.
     
  4. usnavystgc

    usnavystgc Die Hard DIYer and Ebike enthusiast.

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    My diagnosis is, its all heat related. Your battery is nearly twelve, it is in the hot sun and constantly challenged and stressed. Heat is exceptionally hard on a 12 yr old battery and other electrical/electronic components.

    Have you had the steering recall done yet? If not, you should asap.
     
  5. lvsteve

    lvsteve Junior Member

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    I was leaning that direction as every time I've gotten a turtle light, or anything else for that matter, has taken place on a very hot day, and this car has (from all appearances) spent 12 of those summers in the desert. That said, other than a failed invertor pump (which was replaced at no cost by the dealership) I've never had an ounce of trouble.

    I've glanced in the throttle body and seems like nothing is too gunked. I can turn the throttle spring by hand very easily. Also while I had originally thought the oil was just a tad over the dot, it's actually more than a 1/4" so I've got significantly too much oil in there. I'm guessing I need to fix that right away.

    I haven't had the steering recall done, so I'll jump on that.

    Right now it seems to be ok, runs just fine but still shows that orange triangle. Hopefully I'll have some codes this evening.
     
  6. ChapmanF

    ChapmanF Senior Member

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    How is your 12 volt battery doing, by the way? Does the voltage swing down much under load (like when you've got the A/C blowing hard, or turning your steering in a parking space)? There's a reading of the 12V system voltage built into the MFD (if you find the steps to get there elsewhere in this forum) and also even a cheap OBDII scanner ought to be able to show it. (It doesn't even need to communicate with the car for that; one of the pins in the diagnostic connector is 12V supply, so they just measure it.)

    Since you have a strange shifting collection of problems in various systems, I wonder if 12V supply voltage swings could be involved, which is easy enough to rule in or out with a voltmeter before doing anything expensive.

    If you've had some problems with the steering, you can have it blink its codes at you; no need to wait for a special scanner. It turns out that most of the computers in a Gen 1 have the ability to blink their codes if needed if you don't have a scantool. (The steering is unlike the rest in that you have to Bring Your Own Light for it to blink; the others just communicate through different existing lights on the dash.) Many threads in this forum have the details (and so does the shop manual volume 1 on techinfo.toyota.com).

    Two of the computers that are most interesting, though, the Hybrid Vehicle and the Battery ECUs, don't have the blink alternative and you need a Prius-specific scantool of some kind to hear from them.

    I would definitely collect codes before spending much time or money replacing stuff ... I wince every time I read a thread here where someone has spent an arm and a leg on a random heap of parts and finally found the problem pretty much where the codes and the diagnostic tables said to look.

    -Chap
     
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  7. earthpower1

    earthpower1 New Member

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    DON'T let the dealer change the stupid fuel tank and pump until AFTER they do the plugs and get the same codes. Dealer tried that to me, I changed the plugs, kept my same tank and drove the next 120,000 miles just fine.
    jason
     
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  8. usnavystgc

    usnavystgc Die Hard DIYer and Ebike enthusiast.

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    They tried the same thing on me. I refused the service. 40,000+ miles later, no problems with the original tank and pump.