Any signs of the boot splitting, or possibly loose plugs
Valve clatter zero oil pressure (Stall, fails to idle, pending tow - resolved)
- Thread starter divemedic
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- Thread starter
- #22
Would a leak after the maf cause a lean code normally? I don’t believe my scangauge can pull fuel trim data which may help diagnose that? Really wish the truck would at least idle long enough to smoke test it
Pull the pipe after the maf and check for leaks/crack. Your problem sounds like this could be a possibility. it’s hard to see, you’ll have to pull the part out and inspectWould a leak after the maf cause a lean code normally? I don’t believe my scangauge can pull fuel trim data which may help diagnose that? Really wish the truck would at least idle long enough to smoke test it
- Thread starter
- #24
Update and solution. Replaced the crank position sensor and it held an idle for about 30 seconds then died (video below).
Highly recommend everyone pull the sensor to clean it out, a lot of dirt jammed up in there.
At some point while trouble shooting fuel delivery the starter seemed to seize up and the positive battery terminal started getting hot enough to smoke. Que symptoms of a bad ground.
I removed power lines to the winch (need to redo them anyways), disconnected my accessory power panel, the wiring harness for my compressor/front locker/switches, and trailer brake controller.
Cleaned up all the elect rails around the battery. Checked the relays and fuses. Everything seemed to be good to go.
Tried to start, starter acted stuck, but I kept the key in the start position. It struggled slowly like waking up from a nap and fired the engine up. No codes/CEL, ABS light on with alarm. Exhaust smelled rich but held an idle. I shut it down after the idle settled (I did not take a video
). Shut it down, checked the ABS/master cylinder. Nothing remarkable with the pump or relays. All bench tested well.
Started the truck again, same. Truck started and idled perfect. ABS light and alarm was on. I let the idle settle, then pumped the brakes. I could hear the pump engage, on the third pump the ABS light/chime went off. I cranked the AC and let the truck idle until it reached normal temp.
No symptoms of anything. Shut the truck down. Cleaned up my tools. Took it for a test drive around the neighborhood, ran and stopped perfect. Then drove it to get beer. Ran and stopped perfect.
I’m assuming, the several days of trying to start the truck emptied the ABS pump? Pressing the brakes turned on the pump and it did it’s thing? I’m going to keep an eye on all this and report back any changes/updates.
Highly recommend everyone pull the sensor to clean it out, a lot of dirt jammed up in there.
At some point while trouble shooting fuel delivery the starter seemed to seize up and the positive battery terminal started getting hot enough to smoke. Que symptoms of a bad ground.
I removed power lines to the winch (need to redo them anyways), disconnected my accessory power panel, the wiring harness for my compressor/front locker/switches, and trailer brake controller.
Cleaned up all the elect rails around the battery. Checked the relays and fuses. Everything seemed to be good to go.
Tried to start, starter acted stuck, but I kept the key in the start position. It struggled slowly like waking up from a nap and fired the engine up. No codes/CEL, ABS light on with alarm. Exhaust smelled rich but held an idle. I shut it down after the idle settled (I did not take a video
). Shut it down, checked the ABS/master cylinder. Nothing remarkable with the pump or relays. All bench tested well. Started the truck again, same. Truck started and idled perfect. ABS light and alarm was on. I let the idle settle, then pumped the brakes. I could hear the pump engage, on the third pump the ABS light/chime went off. I cranked the AC and let the truck idle until it reached normal temp.
No symptoms of anything. Shut the truck down. Cleaned up my tools. Took it for a test drive around the neighborhood, ran and stopped perfect. Then drove it to get beer. Ran and stopped perfect.
I’m assuming, the several days of trying to start the truck emptied the ABS pump? Pressing the brakes turned on the pump and it did it’s thing? I’m going to keep an eye on all this and report back any changes/updates.
94SRUNNER
GOLD Star
Glad you were able to resolve it!
- Thread starter
- #26
Well headed out for date night and I had a noticeable loss of power, oil pressure tanked and a new chatter from the engine. Chatter got louder so I pulled over.
Video:
The next day I went out, changed to oil to find this:
No change. I’m thinking is valve clatter. Wondering if maybe the oil pump failed causing the clatter? Has anyone had an oil pump fail? Other possible causes or are the stars alighting and it’s literally one break after another?
Valve clatter? You mean rod knock as a result of toasted bearings?
- Thread starter
- #29
That really sounds like a rod knock to me, but sometimes these videos can amplify sounds that are a non issue.
I'll keep my fingers crossed but outlook not so good.Yeah that could be it. Trying to be positive
ramangain
Clarksonian disciple
Sorry to say that sounds "bottom endy" to me.
If the oil pressure really did tank, best not to run the motor much more unless you wanna chance the diagnosis from a catastrophic failure.
If the oil pressure really did tank, best not to run the motor much more unless you wanna chance the diagnosis from a catastrophic failure.
- Thread starter
- #33
alright so… I’ve decided to chase down simple culprits which may cause the symptoms….
Validated the crank position sensor was installed correctly.
Pulled the plugs and CPs. CP number 6 and 5 are both burnt as are the plugs, the plugs where less than hand tight. Remaining plugs/cp seemed fine. (I replaced all plugs and cp concurrently about 40k miles ago).
Left to Right:
2,4,6,8
7,5,3,1
Any reason, aside from the plugs backing out, that CP 5 and 6 would be burnt?
So, I’m going to buy all new plugs and a couple oe replacement cp. put everything together to spec and see how the motor runs. IF it runs well I will get some denso cp to replace and resolve the weeping valve covers. There is evidence that weep is more of a leak.
Any thoughts?
I don’t want to pour money into a broke motor so cheap possibilities are preferred.
I do plan on testing the actual oil pressure after I get new plugs and the oe replacement cp’s to see if it’s possibly a sensor or the oil pump failure.
Validated the crank position sensor was installed correctly.
Pulled the plugs and CPs. CP number 6 and 5 are both burnt as are the plugs, the plugs where less than hand tight. Remaining plugs/cp seemed fine. (I replaced all plugs and cp concurrently about 40k miles ago).
Left to Right:
2,4,6,8
7,5,3,1
Any reason, aside from the plugs backing out, that CP 5 and 6 would be burnt?
So, I’m going to buy all new plugs and a couple oe replacement cp. put everything together to spec and see how the motor runs. IF it runs well I will get some denso cp to replace and resolve the weeping valve covers. There is evidence that weep is more of a leak.
Any thoughts?
I don’t want to pour money into a broke motor so cheap possibilities are preferred.
I do plan on testing the actual oil pressure after I get new plugs and the oe replacement cp’s to see if it’s possibly a sensor or the oil pump failure.
94SRUNNER
GOLD Star
Sounds like a good path forward.
JunkCrzr89
Competent Ignoramoose
Hot Oil leaking out of tube seals in the valve cover and into the tubes.
awesomeissquid
SILVER Star
I could see that explaining cylinder 4, but wouldn't the cylinder 5 CP markings/burns indicate the heat was more originating at the spark plug?
Plugs are known for backing out on these rigs and will likely cause the burning on the cp as a result. I'm guessing the ones with the worst burns were the looser(?) plugs.
ramangain
Clarksonian disciple
Hate to be a Negative Nancy but none of that explains the bottom-endy sound. I'd diagnose the oil pressure issue before tossing more parts at it. I fear oil starvation caused some not insignificant friction-related issues, hopefully not bending metal parts.
If you're buying and putting new parts on this motor to diagnose it - its not a big deal. If you need a new motor, you can swap it all on to the donor and you'll be in good shape.
Depending on how old that oil is, the small amount of flake in it isn't terrible for a motor with that many miles on it.
Do you have a mechanic's stethoscope? Where is the knock coming from on the motor? It's tough in the video to pinpoint the sound of that knock. Is there a substantial vibration in the motor?
Depending on how old that oil is, the small amount of flake in it isn't terrible for a motor with that many miles on it.
Do you have a mechanic's stethoscope? Where is the knock coming from on the motor? It's tough in the video to pinpoint the sound of that knock. Is there a substantial vibration in the motor?
- Thread starter
- #40
I agree fully. I’ll check the plugs gap, maybe buy new ones all around and some cheap cp. Tighten everything to tolerance. Get a mechanical pressure gauge to see actual oil pressure when I turn it on next. Fingers crossed, I’ve got oil pressure and knock/clatter goes away. I’m banking on the odds of an oil pump failure which, for the 2UZ is not common.
If that goes as I hope, I will replace the oil pressure sensor, get the valve cover kit from Wits End along with two new denso cp’s.
If the knock persists along with zero oil pressure I’ll likely sell the truck as is (market value less $5k for a new motor). I don’t have the time or energy to drop a motor in this truck and quite honestly I really don’t need a built 100 and a built 77. In all reality I’ll probably sell for the reasons mentioned above. The difference being the list price.
