Long crank when warm - Issue after valley pan repair

[jmanscotch]

Man, that’d be handy to find one locally, but I’d think the only facilities that’d have a GX would be something like Copart or similar and not a traditional junk yard I could easily pull-n-pay the parts. Would be nice though!

I’ve got my list of prioritized items to work through, just don’t have time right now to tinker with them. Soon, hopefully.

 

[r2m]

While I don't have anything to contribute to solving your issue, I have to say this is one of the most well written and articulate threads I've ever read. I've enjoyed reading it and have a learned a lot, albeit at your expense. I hope you can power through and find the root cause. Just a thought, maybe find a wrecked GX that you pull parts off for troubleshooting?

Unfortunately our GX's are not like Tacoma's or 4R's in sales numbers. There are an absolute ton of Tacoma's and 4R's out there that people total all the time and available in wrecking yards. But GX's sales are very low in comparision and given that most are soccer Mom's, which means they are always driving cautiously (read: less accidents), there just aren't many to pull from.
Just to give an example for 2020 sales, and mind you that 2020 was a very good year for GX sales!

• GX 460: 28,519
• 4Runner: 129,052
• Tacoma: 218,805

 

[jmanscotch]

Found time to reinstall the rebuilt and leak checked original fuel injectors as well as install some fuel line heat shield and so far, it’s good news.

Twice now I’ve got it up to temp and let it sit for an hour and it starts up like normal, no long crank. I’ll check some more tomorrow to make sure, but it was a very repeatable issue and it failed to do it twice in a row, which is very promising.

I’m not sure which of those two things were the issue in the end. I’d be split 50/50 if I had to guess.

Here’s the fuel line heat shield I installed on the two crossover fuel lines, one on the rear of the intake manifold and the other routes in front of the intake manifold. Both these lines route close to coolant lines (rear near some EGR cooler lines and front near a coolant housing section on the engine block) and could’ve been causing fuel vaporization after the fuel lines soaked up heat from the cooling system when parked. Both lines were sort of messed with when doing the coolant valley pan repair, and potentially routed closer than normal to the coolant lines when reassembled.

 

[Acrad]

Fingers crossed for you this fixes it... I will be honest... your experience gave me a little pause to undertake this myself if this ever occurred to me but if this fixes it a definite extra check for someone to look out when doing the work themselves.

 

[jmanscotch]

Never mind.

I just left it for about 1.5 hours and it exhibited the long crank again. It’s always done it at the one hour mark, religiously almost. Apparently twice it was willing to not do it yesterday and be a big tease, bastard.

Next up, I’m dropping the damn thing off at dealership to look at it. I’m contemplating the worth of bribing the technician, with a couple hundred bucks, to motivate him to really dive deep and thorough into it and not just perform their basic surface systems check.

 

[Tex68w]

Man this sucks as it's totally unusual for these trucks. My only hope for you is that it's something totally minuscule and blatantly obvious once you track it down. Fingers crossed this gets resolved ASAP.

 

[Acrad]

jmanscotch: Just to show my support... I'll sponsor you for an hour of labor...even at a Lexus dealer so we know what that cost would be. If interested.. just PM me and we can do via Paypal. I really think it is important we get a clear resolution to this issue. Unfortunately the valley plate leak is a little more common than I'd like to see and a clear means for those affected to resolve this issue themselves at home will benefit the 460 community immensely.

You have very detailed thread that will benefit many but we need to help with closure.

 

[jmanscotch]

Thanks @Tex68w me too. At this point, it’s gotta be something simple, yet hard to locate with no codes, like a sensor getting heat soaked or the computers getting bad data at that particular point in time.

I have a new coolant temp sensor I’m going to throw in, but the temp reads fine on the stock gauge and on my scan gauge, so I doubt it’s that, but I have it and it’s an easy fast swap, when I get time.

Could possibly be a crankshaft position sensor, fuel pump control module or something along those lines. I’m just done messing with it myself finally and am hopeful of stumbling upon some competent and thorough technician that’ll solve it once and for all.

I’ll keep updating here when I find more out.

 

[jmanscotch]

Thanks @Acrad, y’alls support here has helped me not just drive the thing into a ditch and call it a day.

Thankfully, money isn’t a problem. The GX is paid for and I consider repairs to be my equivalent of a car payment. I appreciate the kind offer, but it’ll be going somewhere to have them look at it anyways. The only way we won’t get an answer is if I go to a few more shops and they’re never successful in troubleshooting it. At some point, I’ll just eat my losses and move on to a new vehicle.

What’s kept me from going to a dealership or Indy initially is simply a lack of faith they’d put more effort into it than I myself would. Also a bit of thinking it’d be something easy that I could fix quickly.

Realistically, I’m thinking the issue is somehow cause by my actions and not inherent with the valley pan repair. I know there’s a fair chance a sensor got knocked loose, leaned on, rerouted and wires are sitting on something hot, etc.

There’s also a chance I created some electrical issue with shorting out the positive and negative battery cables (in an effort to reset the traction, ABS and other lights when they came on right after the repair) and burnt up some connection/portion of an ECU or module.

I’m going to start at the dealership and see what we can find out there. If that’s fruitless, I’ll hunt for a good Indy shop again. I’ll have to wait to decide what happens after that, but I’m guessing it’ll sound a lot like a trade in on a Tundra.

 

[Tex68w]

At least wait for the new Tundra if you end up down that path.

 

[jmanscotch]

At least wait for the new Tundra if you end up down that path.

I wish, I’m loving where they’re going with the styling.

That said, I’m too cheap to buy brand new, which is also why I drive a 2010 GX. I don’t like debt and prefer to buy vehicles outright...and a $60k Tundra would be a stretch of what I’m comfortable dropping on a vehicle.

My brother has a newer (‘18 or ‘19) Tundra 1794 that I’m a big fan of, their sorta King Ranch equivalent, which has an awesome interior. I’ve recently started hinted to him that I want it as he’s mentioned he’s getting ready to get a bigger truck for RV hauling.

I’d get the brother deal from him and probably get it for a bit less than trade in value, which I could live with.

 

[Tex68w]

My BIL drives a white 1974, he loves it. I understand not wanting debt in a car, sadly they are all depreciating assets aside from a very very select few.

 

[Acrad]

I bumped out to the Lexus/Toyota mechanics by trade on GXOR as well

 

[jmanscotch]

Appreciate that man, I don’t have Facebook so I miss out on some of those resources.

Just talked with the wife about it all and she’s trying to keep me grounded. Keeps mentioned it does run fine, doesn’t ever not start, so why not just keep driving it for a few years. I guess we’ll just have to wait and see though, I don’t like living with car issues, even if they’re not crippling. It just gets under my skin and isn’t something I have a history of being able to live with.

 

[karmabiker]

Some feedback form GXOR ... hope this helps.

 

[jmanscotch]

Some feedback form GXOR ... hope this helps.

View attachment 2663394

Thanks for the share!

Only catch is I’ve replace all things (that I’m aware of) that would bleed off fuel pressure:

- entire fuel pump assembly (and I think that includes the internal tank regulator/check valve)
- fuel pressure regulator on the fuel rails
- fuel injectors

Also, a fuel bleed back would explain potential fuel vaporization in the lines, as pressure helps hold that process at bay, but sheer lack of fuel present in the system doesn’t account for the ability for it to cold start fine after sitting.

If I could find a fair prices fuel pressure gauge that’d fit this setup, I’d have zero problems with running the test though.

 

[jmanscotch]

Random thought, what about the idea that an EGR valve is stuck open?

Could run normal, not sure if that’d trigger a CEL, then when sitting, the exhaust gasses are making their way into the intake/MAF area and heating that up, causing the ECU to call for less fuel on warm startup, until the air in the intake turns over fresh and the air/fuel mixture corrects. Would work with the idea of the vehicle cooling off completely and starting normal again too.

 

[Sargy]

Following.

Wishing you the best of luck. We don't have the same rig but I have an extended crank issue that I am trying to figure out myself.

 

[jmanscotch]

No update on the problem, but need to vent a bit about shops.

I really don’t have much faith in the dealership route, so I opted to first call/stop by all the independent shops in town. I found any who mentioned Japanese vehicles as a focus or any “troubleshooting” type reviews and man is it pathetic out here.

3 out of the 4 shops straight told me some version of they have easier money to make and don’t want to mess with it. One told me I was being difficult by not being ok with a long crank, “it starts doesn’t it, why won’t you call that good enough? I don’t think we’d be willing to look at it”.

Others pretty much said they didn’t want to look at it because “it sounds like I’ve hit everything they’d check, so it’s going to be hard”. The last shop just generally lacked confidence, said they didn’t do much in depth troubleshooting like this, but they’d look at it.

Anyone here a Toyota/Lexus/hungry tech near Colorado? I’d pay cash and shop rate for you to check it out...seriously.

Anyone have advice on the best way to approach this diag at the dealership? Is there a type of tech I should ask to work on it, is oversharing information on the problem better or worse for their troubleshooting? Do I leave a note in the car that describes symptoms and parts already replaced? Thats all somewhat painful details to try to relate effectively through SAs, in my experience, but maybe that’s still a better way.

 

[jmanscotch]

Promising update:

I dropped the truck off last week at a import shop in town. They’ve had it for over a week and have been working through everything trying to figure it out.

I received a call today and they’ve been able to confirm the issue is seemingly being cause by excessive hydrocarbons in the intake manifold. If the tech parks the truck and uses compressed air to evacuate the stagnant air in the intake manifold, then the long crank symptoms don’t happen.

Now that the direct cause is identified, they’re going to work on narrowing down the root cause, which sounds like it could really be a small handful of things, so I’m confident they’ll have more information soon.

In the meantime, I’m enjoying transportation in the form of my buddies Ducati 848 and BMW R1200GS...keeps my mind off the Lexus problems quite well.