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2007 Black FJC
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Discussion Starter · #1 · (Edited)
EDIT: not to spoil the "who done it", but the fuel pump was the problem, saturated with dust and fine sand. See this link

Thought I'd put this out to the general brain trust and also see if there are any auto mechanic shops in Moab that are recommended.

I started having power drop off issues while accelerating yesterday (very minor), but today they became a major problem. The power will drop dramatically, my scan gauge comes up with p0171 and sometimes p0174 (lean mixture errors, both), and I get the "engine check, vsc, etc." christmas tree lights on dash.

p0171 and p0174 are lean mixture errors that recommend cleaning the MAF (which was done before the trip and again today after the error - no effect), checking air filter (done, clean), and checking vacuum hoses (done, and as best I can tell, fine). I checked out the following link, which seems similar to my error, but mine is intermittent:

this link

Also, I had tried to see if it was low-grade gas that was doing it. On less than 1/4 tank full, I filled with premium. Thought I was a genius as it ran great and at full power (up hill past Arches and at like 75mph), but after turning around and coming back to Moab, I got it again slightly. It seems to get worse as the tank empties alittle, but maybe I'm imagining that. Based on the above thread, I will change my spark plugs tomorrow, but I'm running out of ideas.

That brings me to: any good auto place in Moab that might have a clue about our FJC engines and systems?

Thanks :cowfrown:
 

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Thought I'd put this out to the general brain trust and also see if there are any auto mechanic shops in Moab that are recommended.

I started having power drop off issues while accelerating yesterday (very minor), but today they became a major problem. The power will drop dramatically, my scan gauge comes up with p0171 and sometimes p0174 (lean mixture errors, both), and I get the "engine check, vsc, etc." christmas tree lights on dash.

p0171 and p0174 are lean mixture errors that recommend cleaning the MAF (which was done before the trip and again today after the error - no effect), checking air filter (done, clean), and checking vacuum hoses (done, and as best I can tell, fine). I checked out the following link, which seems similar to my error, but mine is intermittent:

this link

Also, I had tried to see if it was low-grade gas that was doing it. On less than 1/4 tank full, I filled with premium. Thought I was a genius as it ran great and at full power (up hill past Arches and at like 75mph), but after turning around and coming back to Moab, I got it again slightly. It seems to get worse as the tank empties alittle, but maybe I'm imagining that. Based on the above thread, I will change my spark plugs tomorrow, but I'm running out of ideas.

That brings me to: any good auto place in Moab that might have a clue about our FJC engines and systems?

Thanks :cowfrown:
A P0171 AND P0174 usualy get flaggen when you get unmetered air through the intake that is not getting measures by the MAF. It is a correlation betweeen the upstream 02 sensors. Check for damage to the upstreams 02 sensors or leaks in you intake tract.
 

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I think it's the air flow meter....at least that was one of the codes I was getting on my 4Runner.

On it, it's located immediately upstream from the airbox. I think it was a rather expensive ($160 IIRC) part from Toyota.

I'm not sure though....just throwing it out there. I unfortunately lost my paperwork I thought I had with my OBDII scan gauge.

Sean
 

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2007 Black FJC
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Discussion Starter · #4 ·
Thanks guys. I went outside again eye-balled the outside of the air pathway and couldn't see anything (nothing obviously cracked or open). Now I guess the issue is: do I try and limp back to someplace where there's a Toyota shop or try a auto place here? Not sure the former is practicable since it'll slow from a nice 75mph down to a freeway scary 30mph or less before the power kicks back in...
 

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An auto shop there should be able to diagnose it....if they are familiar with Toyotas....but they'll have to order the part anyway if it's what was wrong with mine.

Either way, you're going to have to get the part from Toyota most likely.

Sean
 

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Before the trouble started did you fill up the tank? Maybe there is water in the fuel system?

Have you tried any high-strength fuel system cleaners?
 

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2007 Black FJC
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Discussion Starter · #7 ·
It started today (properly) after we'd gone from Moab, up Long Canyon to Grand View Point in Canyonlands, then all the way down Shafer Trail. We were exiting by Potash and it just started playing up. (It had done it like twice before that, just for an instant in both cases). The tank was like 1/4 full when it happened. Filling the tank with 91 octane (not sure which part of that helped if any) seemed to fix it for like 10 miles. Then it came back.
 

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It started today (properly) after we'd gone from Moab, up Long Canyon to Grand View Point in Canyonlands, then all the way down Shafer Trail. We were exiting by Potash and it just started playing up. (It had done it like twice before that, just for an instant in both cases). The tank was like 1/4 full when it happened. Filling the tank with 91 octane (not sure which part of that helped if any) seemed to fix it for like 10 miles. Then it came back.
Possibly clogged fuel filter? Loose or cut vacuum line?

Another train of thought is that the MAF may have actually been damaged when you cleaned it before the trip. I am just going from the "cause and effect" train of thought by asking "What was recently touched, changed or adjusted?"


Saw this:

Possible solutions include:

In the vast majority of cases, simply cleaning the MAF sensor does the trick. Consult your service manual for it's location if you need help. I find it's best to take it off and spray it with electronics cleaner or brake cleaner. Make sure you are careful not to damage the MAF sensor, and make sure it's dry before reinstalling
Inspect all vacuum and PCV hoses, replace if necessary
Check for a dirty fuel filter and proper fuel pressure


...and you already cleaned the MAF but what if it is faulty?
 

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Maybe double check the MAF connector and wires too....
 

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Just speculation here but I'd say either fuel filter or MAF

Didn't Team Millen have an issue in that 2 roads to Baja show
I think their FJ was losing power and then finally wouldn't even start
I think they bypassed the MAF

Good luck and hope you get your FJ feeling better ASAP!!
 

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Discussion Starter · #11 ·
Just speculation here but I'd say either fuel filter or MAF

Didn't Team Millen have an issue in that 2 roads to Baja show
I think their FJ was losing power and then finally wouldn't even start
I think they bypassed the MAF

Good luck and hope you get your FJ feeling better ASAP!!
do you remember how they by-passed the MAF?
 

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Don't think they showed much in the DVD but they were down for a few hours trying to get the FJ to start and stay running. This post mentions the troubles but isn't specific on the fix.

FJ Cruiser finished 2nd in the Baja 1000 - IH8MUD™ Forums
Post 16
Post 22

They also said something about resetting the ECU
But you would have to disconnect the battery and that would lose any error codes that may be stored

Hope that helps
 

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Discussion Starter · #14 ·
I posted this up a little while ago on my build up page (also have some moab pictures on there). Made it back to LA, but the truck didn't. Will know from the Vegas dealership what exactly failed by mid week. MAF sensor failure seems likely as the thing go worse, like the Millen truck, but who knows...



My truck started getting p0171 and p0174 errors and power drops. It happened once on the Wed when I got into Moab (heavy rain, not sure why I thought that mattered, but it didn't reappear so I figured might have something to do with that). Anyway, Friday afternoon it got really bad. The p0171 and p0174 turn out to be lean mixture (too little fuel and/or too much air). The mass air flow (MAF) sensor is often to blame - we cleaned it with CRC MAF cleaner (yup there is something that specific). No help. We fooled ourselves briefly that it was cheap gas. The problem kept being sporadic but getting worse (a lot of variation around a mean worsening trend - kind a like global warming - alot of opportunity to think, "huh, the problems gone now"). Anyway, not the case, kept getting worse. Given the complexity of the engine, I figured I needed to get it to a place where they had Toyota-specific tools / scanners. I decided to bail on the white rim trail and get to a dealership. Nearest one open on Sat: Denver, SLC, or Vegas. Vegas is on way home, so off I set. No real problem till the climb up central Utah on the 70 - but still not major issue. Started to get tetchy by the 15. Filled up in Cedar City and all of a sudden it's like the truck is new - cruising at 75 mph, no problems. I get to St George and am hungry, so stop at Wendys (that detail turns out not to be important to the story, I just love the fried chicken sandwich, no mayo, with lots of bbq sause). Back on the road and the FJC is a pig, very little power even down hill. The narrow section of the 15 thru the virgin river channel is a nightmare. By 40 miles from Vegas I'm a moving obstacle on the freeway and I pull onto a side road that parallels the 15. I'm calling up the dealerships and find one still open. Power kicks in a bit and to nav to the dealership I get back on the freeway. Nightmare - lots of honks and a very visible and obvious obstacle - I get off on flamingo. I ended up just about crawling into the Desert Toyota dealership, where the truck now rests. Got some interesting looks as I pulled into the service bay - just barely in time, the shutters came down almost immediately after I rolled in. Got the SWA 8pm back to LAX. We'll see what the dealership says.
 

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Mark, I replied in your build thread, but didn't see this thread until now. In addition to MAF, I'd look into possible clogged fuel filter and if you have a CAI, check the connector to the fuel pressure regulator. You may have a vacuum leak.
 

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Discussion Starter · #17 ·
Mark, I replied in your build thread, but didn't see this thread until now. In addition to MAF, I'd look into possible clogged fuel filter and if you have a CAI, check the connector to the fuel pressure regulator. You may have a vacuum leak.
What I could inspect from the engine bay and from crawling under the rig I did. Everything looked clean. We did clean the MAF. Hoses looked good. Air filter was clean. The other stuff was beyond what I could do - and I guessed most were beyond what a non-Toyota place could fix.

I'll write up a full report on what happened when I find out. There may be lessons learned re: spares to carry (e.g. MAF sensor). But if it's a fuel filter problem due to the E10 (like reported elsewhere on the forum), then we may all need to have a serious think about what to do.
 

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Discussion Starter · #19 ·
I wonder...is a fuel filter made that will fit our trucks that will not explode with E80+?
At the dealership the first they asked with a kind of "your fault" grimace was if I'd used E85 in there. I don't know if they have tougher filters. If filter is the problem, it'll be the first thing I research.

(BTW: nope on the E85, most I'm guilty of is occasional 85 octane E10.)
 

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What I could inspect from the engine bay and from crawling under the rig I did. Everything looked clean. We did clean the MAF. Hoses looked good. Air filter was clean. The other stuff was beyond what I could do - and I guessed most were beyond what a non-Toyota place could fix.

I'll write up a full report on what happened when I find out. There may be lessons learned re: spares to carry (e.g. MAF sensor). But if it's a fuel filter problem due to the E10 (like reported elsewhere on the forum), then we may all need to have a serious think about what to do.
Forgive my ignorance, but what's so special about the FJC's fuel filter? I'm assuming it's standard Toyota fare and is an internal style pump with an external filter.....wouldn't you just carry a spare?

Just curious,
Sean
 
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