No start condition

[ShenValley100LC]

Any time I hear crank no start, the very first thing I want to check is the fuel delivery. The fuel relay in driver side D pillar (left side of the rear hatch) can go bad and will cause this too!

I unhooked fuel line to the fuel filter and its pumps with pretty good pressure when cranking..

which actually...now that I think of it if it was a short or issue with the crankshaft position sensor--would it cut off the fuel pump too or only spark/ignition? IOW if I am getting fuel delivery does that mean the computer is not cutting off ignition for some kind of sensor or something....?

 

[ClassyJalopy]

I unhooked fuel line to the fuel filter and its pumps with pretty good pressure when cranking..

which actually...now that I think of it if it was a short or issue with the crankshaft position sensor--would it cut off the fuel pump too or only spark/ignition? IOW if I am getting fuel delivery does that mean the computer is not cutting off ignition for some kind of sensor or something....?

As you know you only need three things for an engine to fire up fuel, ignition and compression.
Fuel you just confirmed, compression doesn't disappear overnight (not usually at least) so it must be the ignition.

BTW, I think getting the fuel pumped in also rules out the EFI issue (EFI Relay Bypass Kit (Immobilizer Fix) for UZJ100/LX470 - https://forum.ih8mud.com/threads/efi-relay-bypass-kit-immobilizer-fix-for-uzj100-lx470.952811/)

 

[ShenValley100LC]

As you know you only need three things for an engine to fire up fuel, ignition and compression.
Fuel you just confirmed, compression doesn't disappear overnight (not usually at least) so it must be the ignition.

So here's my thing about ignition...I had just drove the car the day before. No cylinder misfires, isn't it highly unlikely that overnight multiple spark plugs/coils stopped firing? It seems more something (like a sensor read out) is preventing them from firing (provided I have compression, etc...) Current spark plugs and starter have less than 50K on them, seems very unlikely (coils I have no idea, but a Toyota dealer looked at them 50K miles decided they were fine.

But I havent heard back definitively from anyone whether a crankshaft sensor would prevent fire up but not fuel pump from working. It seems like it would prevent both.

BTW, I think getting the fuel pumped in also rules out the EFI issue (EFI Relay Bypass Kit (Immobilizer Fix) for UZJ100/LX470 - https://forum.ih8mud.com/threads/efi-relay-bypass-kit-immobilizer-fix-for-uzj100-lx470.952811/)

Yes, I think I've completely ruled this out. The immobilizer light shuts with the key in, fuel is pumping, and I did the direct wire from battery to EFI relay just to triple check...

I'm trying to find someone local with Techstream to see if there are codes I'm not picking up but so far no luck.

compression doesn't disappear overnight (not usually at least)

So...about that...I guess should give more details and voice a sudden fear and anxiety that just came over (though it seems unlikely). When I tried the very first time in the morning to start the car it did kind of start, sputter, and stop. Rpm went up briefly (less than half a second) struggled and stopped. Is it possible the timing belt broke on start (for a very specific reason I'll explain in a second), so crankshaft is turning, fuel pump works but now valves and everything else not turning? When I did the timing belt (over a year ago) I discovered I was missing the small dust cover piece for the middle and ordered one but it didnt come in time and I needed the car so I put it together without it. Well the night before the truck wouldnt start was very cold and we have problems with mice (and birds) from the field next to us seeking shelter in our garage and in the cruiser engine bay (taken multiple birds nest out of it). I've heard horror stories of people with this dust cover missing and mice making a home in their and actually causing the timing belt to jump off on start up.....seems far fetched and wild.....but now I kind feel the need to take the timing belt cover off just to relieve my anxieties.....

So supposing I taking the drivers side timing belt cover off (easiest one to get to I think). What else could it be? Could extreme head gasket failure cause total loss of compression overnight with no warning, no oil loss, and no known overheating? Could something internal have finally bit the dust like piston rings or something? I just had an oil test on this truck with virtually no signs of wear on internal components in the oil...but its 520K miles so anything possible I guess. Damn just typing this is stressing me out.

Someone just tell me its gonna be alright!?!? Hold me and tell me I'm going to make to a million miles!!!

 

[medtro]

I unhooked fuel line to the fuel filter and its pumps with pretty good pressure when cranking..

which actually...now that I think of it if it was a short or issue with the crankshaft position sensor--would it cut off the fuel pump too or only spark/ignition? IOW if I am getting fuel delivery does that mean the computer is not cutting off ignition for some kind of sensor or something....?

This may not a reliable way to confirm fuel pump functionality unless you know the fuel pressure. I had fuel came out of the fuel line to fuel filter but engine wouldn't start. It started with starting fluid. New fuel pump solved the problem.

You may want to check for spark if you haven't done it already. If no spark then it is electrical problem.

 

[ClassyJalopy]

So here's my thing about ignition...I had just drove the car the day before. No cylinder misfires, isn't it highly unlikely that overnight multiple spark plugs/coils stopped firing? It seems more something (like a sensor read out) is preventing them from firing (provided I have compression, etc...) Current spark plugs and starter have less than 50K on them, seems very unlikely (coils I have no idea, but a Toyota dealer looked at them 50K miles decided they were fine.

But I havent heard back definitively from anyone whether a crankshaft sensor would prevent fire up but not fuel pump from working. It seems like it would prevent both.

Yes, I think I've completely ruled this out. The immobilizer light shuts with the key in, fuel is pumping, and I did the direct wire from battery to EFI relay just to triple check...

I'm trying to find someone local with Techstream to see if there are codes I'm not picking up but so far no luck.


So...about that...I guess should give more details and voice a sudden fear and anxiety that just came over (though it seems unlikely). When I tried the very first time in the morning to start the car it did kind of start, sputter, and stop. Rpm went up briefly (less than half a second) struggled and stopped. Is it possible the timing belt broke on start (for a very specific reason I'll explain in a second), so crankshaft is turning, fuel pump works but now valves and everything else not turning? When I did the timing belt (over a year ago) I discovered I was missing the small dust cover piece for the middle and ordered one but it didnt come in time and I needed the car so I put it together without it. Well the night before the truck wouldnt start was very cold and we have problems with mice (and birds) from the field next to us seeking shelter in our garage and in the cruiser engine bay (taken multiple birds nest out of it). I've heard horror stories of people with this dust cover missing and mice making a home in their and actually causing the timing belt to jump off on start up.....seems far fetched and wild.....but now I kind feel the need to take the timing belt cover off just to relieve my anxieties.....

So supposing I taking the drivers side timing belt cover off (easiest one to get to I think). What else could it be? Could extreme head gasket failure cause total loss of compression overnight with no warning, no oil loss, and no known overheating? Could something internal have finally bit the dust like piston rings or something? I just had an oil test on this truck with virtually no signs of wear on internal components in the oil...but its 520K miles so anything possible I guess. Damn just typing this is stressing me out.

Someone just tell me its gonna be alright!?!? Hold me and tell me I'm going to make to a million miles!!!

Relax! Even if the TB went kaput you got nothing to worry about. These engines are non-interference kind (unlike my siblings! perhaps non-interfering is the word I was looking for there, but I digress!).

In all likeliness it is not the TB issue, perhaps, some critter chewed off a wire somewhere?

Also, what @medtro said below:

This may not a reliable way to confirm fuel pump functionality unless you know the fuel pressure. I had fuel came out of the fuel line to fuel filter but engine wouldn't start. It started with starting fluid. New fuel pump solved the problem.

You may want to check for spark if you haven't done it already. If no spark then it is electrical problem.

 

[ShenValley100LC]

Relax! Even if the TB went kaput you got nothing to worry about. These engines are non-interference kind (unlike my siblings! perhaps non-interfering is the word I was looking for there, but I digress!).

In all likeliness it is not the TB issue, perhaps, some critter chewed off a wire somewhere?

Also, what @medtro said below:

Yeah its probably not that... but I read about it happening to some rando on MUD so now I'm paranoid about it....

This may not a reliable way to confirm fuel pump functionality unless you know the fuel pressure. I had fuel came out of the fuel line to fuel filter but engine wouldn't start. It started with starting fluid. New fuel pump solved the problem.

You may want to check for spark if you haven't done it already. If no spark then it is electrical problem.

I did try to start it with starter fluid and it was a no go.

 

[tshandonay]

So here's my thing about ignition...I had just drove the car the day before. No cylinder misfires, isn't it highly unlikely that overnight multiple spark plugs/coils stopped firing? It seems more something (like a sensor read out) is preventing them from firing (provided I have compression, etc...) Current spark plugs and starter have less than 50K on them, seems very unlikely (coils I have no idea, but a Toyota dealer looked at them 50K miles decided they were fine.

But I havent heard back definitively from anyone whether a crankshaft sensor would prevent fire up but not fuel pump from working. It seems like it would prevent both.

Yes, I think I've completely ruled this out. The immobilizer light shuts with the key in, fuel is pumping, and I did the direct wire from battery to EFI relay just to triple check...

I'm trying to find someone local with Techstream to see if there are codes I'm not picking up but so far no luck.


So...about that...I guess should give more details and voice a sudden fear and anxiety that just came over (though it seems unlikely). When I tried the very first time in the morning to start the car it did kind of start, sputter, and stop. Rpm went up briefly (less than half a second) struggled and stopped. Is it possible the timing belt broke on start (for a very specific reason I'll explain in a second), so crankshaft is turning, fuel pump works but now valves and everything else not turning? When I did the timing belt (over a year ago) I discovered I was missing the small dust cover piece for the middle and ordered one but it didnt come in time and I needed the car so I put it together without it. Well the night before the truck wouldnt start was very cold and we have problems with mice (and birds) from the field next to us seeking shelter in our garage and in the cruiser engine bay (taken multiple birds nest out of it). I've heard horror stories of people with this dust cover missing and mice making a home in their and actually causing the timing belt to jump off on start up.....seems far fetched and wild.....but now I kind feel the need to take the timing belt cover off just to relieve my anxieties.....

So supposing I taking the drivers side timing belt cover off (easiest one to get to I think). What else could it be? Could extreme head gasket failure cause total loss of compression overnight with no warning, no oil loss, and no known overheating? Could something internal have finally bit the dust like piston rings or something? I just had an oil test on this truck with virtually no signs of wear on internal components in the oil...but its 520K miles so anything possible I guess. Damn just typing this is stressing me out.

Someone just tell me its gonna be alright!?!? Hold me and tell me I'm going to make to a million miles!!!

I watched a YouTube video a few weeks ago (Mustie1 is the channel) He had a rough running Tundra with the 4.7. He pulled the timing covers and discovered a pancaked mouse that got caught in the belt and caused it to jump.

 

[ramangain]

I watched a YouTube video a few weeks ago (Mustie1 is the channel) He had a rough running Tundra with the 4.7. He pulled the timing covers and discovered a pancaked mouse that got caught in the belt and caused it to jump.

That is WAY too kind of a description of the mouse

 

[2001LC]

It pays to investigate service history, as I've found many issue using it as my guide of where to look.

Easiest way to check timing belt, is by pulling RH (PS side) t-belt cover. But it still many be necessary to peak in at LH side mark, if RH lines up. It is possible to remove LH cover bolts & nut and sneak a peak at cam timing mark, without remove cover all the way.

Rodent damage is a pain. We saw a few year back in mud, a mouse get in and take out a belt because that little triangular cover not installed during a T-belt service. They may also crew on the cam sensor wire inside.

All to often, the crank sensor and oil sending units wires are routed wrong or wires of cam sensor not routed and secured properly. This can lead to wires rubbing and being cut by drive belt. A visual check can be revealing. I re-did a timing job last week, that a Lexus Dealership had done. I was just going to pull fan bracket and re-rout wires the proper way. But on check Lexus parts list for the t-belt job they did, by calling Lexus parts department. I learned they did not replace the timing belt pulleys or tensioner. I also had oil weep on lower front right side of engine. What a mess I found; bolts not torqued, missing bolts, busted timing covers, sealant not used on tension pulley bolt (oil weep), bad pulley bearing, busted wire housing clips the list goes on.

Lexus history also showed; wire repair from rodent damage. I found the repair, a VVT cam sensor wire, not done with best practice.

 

[ShenValley100LC]

It pays to investigate service history, as I've found many issue using it as my guide of where to look.

Easiest way to check timing belt, is by pulling RH (PS side) t-belt cover. But it still many be necessary to peak in at LH side mark, if RH lines up. It is possible to remove LH cover bolts & nut and sneak a peak at cam timing mark, without remove cover all the way.

Rodent damage is a pain. We saw a few year back in mud, a mouse get in and take out a belt because that little triangular cover not installed during a T-belt service. They may also crew on the cam sensor wire inside.

All to often, the crank sensor and oil sending units wires are routed wrong or wires of cam sensor not routed and secured properly. This can lead to wires rubbing and being cut by drive belt. A visual check can be revealing. I re-did a timing job last week, that a Lexus Dealership had done. I was just going to pull fan bracket and re-rout wires the proper way. But on check Lexus parts list for the t-belt job they did, by calling Lexus parts department. I learned they did not replace the timing belt pulleys or tensioner. I also had oil weep on lower front right side of engine. What a mess I found; bolts not torqued, missing bolts, busted timing covers, sealant not used on tension pulley bolt (oil weep), bad pulley bearing, busted wire housing clips the list goes on.
View attachment 2593886
Lexus history also showed; wire repair from rodent damage. I found the repair, a VVT cam sensor wire, not done with best practice.

In this case I did the timing belt just over a year ago, and I happen to know I didn't put in the triangular cover piece because it didn't come in in time and I needed the truck. All I could see from the below the truck with splash guard off was the oil sending unit and a small part of the crank sensor wiring but it looks fine no evidence of rubbing against anything, but I cant see much on the crank sensor.

Today I think I'll grab a spark tester and give that a check. If that's ruled out I guess I peel back the timing cover and see what I can find. It just doesn't sound like a good option to basically do all the work of a timing belt job just because I have no idea what it is.

 

[2001LC]

Yeah, I did see you did have the small cover in time for assembly, and that you rodent issue in area.

No need to get a spark tester

 

[ShenValley100LC]

Yeah, I did see you did have the small cover in time for assembly, and that you rodent issue in area.

No need to get a spark tester

View attachment 2593913


View attachment 2593914

Well, that makes it easier. Is the next place to check just the timing belt rabbit hole?

 

[medtro]

Adding more stuff to your check list. Someone sent this to me today.

The starting issues ended up being the cam position sensor.

 

[ShenValley100LC]

Adding more stuff to your check list. Someone sent this to me today.

Yeah it just sucks that there apparently is no way of checking this? By the time I get to the cam sensors I've done all the work of replacing it. How do I know if its the cam or the cranks sensors? Does anyone know if the cam shaft position sensor or crankshaft position sensor will throw a code or be evident in OBDII? If it is a camshaft or crankshaft position sensor will it prevent spark plugs from firing or fuel pump from pumping?

 

[ShenValley100LC]

Yeah, I did see you did have the small cover in time for assembly, and that you rodent issue in area.

No need to get a spark tester

View attachment 2593913


View attachment 2593914

So, I have spark.....

 

[medtro]

Yeah it just sucks that there apparently is no way of checking this? By the time I get to the cam sensors I've done all the work of replacing it. How do I know if its the cam or the cranks sensors? Does anyone know if the cam shaft position sensor or crankshaft position sensor will throw a code or be evident in OBDII? If it is a camshaft or crankshaft position sensor will it prevent spark plugs from firing or fuel pump from pumping?

Do you have FSM?

 

[ShenValley100LC]

Do you have FSM?

I do (pdf at least). Anyways, opened the timing belt cover last night. It was a mouse in the timing belt...what are the odds

DO NEGLECT THE $5 DUST COVER (also need some advice)

So, as some may know the 500K mile Tiki Cruiser would not start this weekend. Or rather, it started up and almost immediately shut off and then would only crank/no-start. After multiple tests and rabbits holes chased after 6+ hours of reading threads on my mud. I took the off the passenger side...

forum.ih8mud.com

 

[mdcoa]

I do (pdf at least). Anyways, opened the timing belt cover last night. It was a mouse in the timing belt...what are the odds

DO NEGLECT THE $5 DUST COVER (also need some advice)

So, as some may know the 500K mile Tiki Cruiser would not start this weekend. Or rather, it started up and almost immediately shut off and then would only crank/no-start. After multiple tests and rabbits holes chased after 6+ hours of reading threads on my mud. I took the off the passenger side...

forum.ih8mud.com

I'll bet he had a pretty terrifying last couple nanoseconds of life . . . after being so stoked at finding such a cozy spot.

 

[2001LC]

I do (pdf at least). Anyways, opened the timing belt cover last night. It was a mouse in the timing belt...what are the odds

DO NEGLECT THE $5 DUST COVER (also need some advice)

So, as some may know the 500K mile Tiki Cruiser would not start this weekend. Or rather, it started up and almost immediately shut off and then would only crank/no-start. After multiple tests and rabbits holes chased after 6+ hours of reading threads on my mud. I took the off the passenger side...

forum.ih8mud.com

Not the first or the last.

 

[medtro]

I do (pdf at least). Anyways, opened the timing belt cover last night. It was a mouse in the timing belt...what are the odds

DO NEGLECT THE $5 DUST COVER (also need some advice)

So, as some may know the 500K mile Tiki Cruiser would not start this weekend. Or rather, it started up and almost immediately shut off and then would only crank/no-start. After multiple tests and rabbits holes chased after 6+ hours of reading threads on my mud. I took the off the passenger side...

forum.ih8mud.com

I understand you found your problem already.

No need to remove camshaft sensor for checking. Simply disconnect the connector and measure resistance. Resistance specs is in the diagnostic section of the FSM.