97 LX450 Crank strong but No start (1 Viewer)

[hobbes]

Thanks for all the help on this, Satchel. OP has limited mobility, so its probably easier for me to run by and check the voltage across the IGN fuse. I can work backward (fusible links) or forward (ECM pins) from there. That'll probably be all the time I have for awhile.

If the fuel injectors aren't getting power, would a side symptom be a fuel odor? Excess fuel being pumped into the evap? That doesn't really make sense to me...

 

[satchel]

Yeah I was wondering about what would cause the fuel smell too. My only thought is that if the injectors are not firing, that all the fuel being pushed is going right back to the tank and building more pressure than normal, causing more to purge through the charcoal canister?

 

[hobbes]

Yeah, maaaaybeeee. When I pulled the fuel return hose off the pressure regulator, it was a strong stream. But I have nothing to compare it to, so that's a relative statement. I couldn't find any obvious leaks.

It's funny, I've had my 80 series over 15 years. Done all my own maintenance. I've never had to troubleshoot a no-start other than an obvious starter contact. So I'm not really versed at any of this...

 

[lumbee1]

Did you check continuity across the fusible links? I popped a new fusible link when I was searching for a short. The CEL light says the fusible link is good but I would double check.

 

[hobbes]

Did you check continuity across the fusible links? I popped a new fusible link when I was searching for a short. The CEL light says the fusible link is good but I would double check.

I did not. I assumed the solid CEL with the key on meant good-to-go there.

 

[hobbes]

Still broke. Latest update:

1. The ECM voltages highlighted in post #17 all checked good.
2. Correct voltage was on both sides of the IGN fuse.
3. Continuity was verified across all the fusible links.
4. Voltage was checked across 50 amp fuse (AM2?).
5. There's a single wire to a connector running up besides the alternator (looks like it goes to the injectors). Good voltage.
6. Pulled the dizzy cap. Aftermarket, but looked ok. Rotor looked okay, but hit it with a wire brush.
7. The connector on the wire from the coil to the dizzy was broken on the coil (and aftermarket). I replaced it with my trial spare (OEM).
8. Pulled the number 2 spark plug wire and tested the spark w/ one of those visual spark plug testers. We saw a flash.
9. Scangauge still shows no codes, TPS good, and fuel pressure.

OP wants to do a compression check. I'm tepid on the idea. The truck turns over fine. Even if compression was bad, it would run (s***ty).

I saw something in the manual about a VSV under the intake. Any chance that could be it? No way to get to that thing w/o pulling the intake.

Coil pack? Could it be bad even if we seen a spark?

Bad gas? I doubt it. Fuel is only 3 weeks old. Even crappy gas with water should run on some level.

What if the timing belt jumped a cog? The Scangauge shows 5 degrees w/ just key on, same as mine. But I know that's just the electric signal, not the physical location.

IOW, I'm out of ideas.

Edit: the truck does have an alarm system. But if we can see spark...

 

[SUMMIT CRUISERS]

I would check fuel pressure. If possible at the fuel rail. A good stream may be 20 psi but spec is close to 45 to 50. If you got spark and fuel, even if the timing was off, the truck would at least pop and backfire. That’s why I’m thinking fuel related.

 

[ppc]

No timing belt on a 1FZ-FE. The timing chain is not going to slip. Highly unlikely there is a mechanical issue along those lines as the OP stated the engine was running fine before shutting it off. That all points to an electrical issue of some sort.

 

[satchel]

Sounds like the spark side of the equation is good, so for now I would focus on the air/fuel as stated by others above. It's possible if the fpr isn't holding pressure or you are losing pressure for any number of reasons, that the injectors don't have enough pressure to fire. As for the air part, I have no idea how the throttle body on the cruiser works but I'm assuming there is some sort of idle air control valve that lets air through when the blade is closed at idle. I guess it's possible that is clogged or not working otherwise. Maybe try opening the blade while starting just to make sure plenty of air is getting in. Idk, just spewing crap out of my fingers at this point...

 

[hobbes]

There is an IAC. No codes, but I can read up on the test procedures. Same for fuel pressure.

 

[Hankg550]

One day i came home turn her off and the next day she just cranked and cranked but didn’t start
Things i have changed since this Fuel Filter, TPS, and next is the fusible Link i had to PB Blast the screws so that’s happening tonight any way prior to this i checked the codes and 4 codes came up crank sensors which i think i have had disconnected along time ago and closed TPS so i changed that and still nothing i changed the fuel filter and still nothing after the fusible link what are some other approaches i should do ? Please help thank you

I was working on my 300zxtt radio and have to move the gear selector to drive or lower to access. After finishing I tried to start the car up. Would not start. Forgot to move the gear selector back into park. Tried to start the car up and cranked good but no start. Charged my battery fully and afterwards started right up again.

 

[hobbes]

Thanks! We can add that to the list. It “looked” in park, but that’s easy enough to verify. It’s not the Park safety switch. When those go bad there’s no cranking.

 

[OffRoadLife]

Sounds like the spark side of the equation is good, so for now I would focus on the air/fuel as stated by others above. It's possible if the fpr isn't holding pressure or you are losing pressure for any number of reasons, that the injectors don't have enough pressure to fire. As for the air part, I have no idea how the throttle body on the cruiser works but I'm assuming there is some sort of idle air control valve that lets air through when the blade is closed at idle. I guess it's possible that is clogged or not working otherwise. Maybe try opening the blade while starting just to make sure plenty of air is getting in. Idk, just spewing crap out of my fingers at this point...

Someone in here it’s the said that they changed the ignition coil and that was their problem even though we’re getting spark I don’t know how to test the ignition coil itself but I got some information today about checking the timing chain tensioner as well as the timing by taking the distributor cap off and turning the key to see if the distributor moves if it does the chain is connected if it doesn’t the chain came off but he said it’s really unlikely that the chain came off he’s never heard I’m a change coming off I talk to that guy on YouTube who redid Land Cruiser engine that everybody saw I got a chance to talk to him today briefly

 

[hobbes]

We know the distributor moves since we had spark on #1 and #2 plugs. I'll shoot you a PM.

 

[OffRoadLife]

This guy gets a standing ovation if i could stand holy bananas he got it to start amazing

 

[hobbes]

FIXED!

Rookie mistake on my part. On initial survey I noticed the high tension lead from the coil to the dizzy had a broken clip on the coil and the rubber boot was ajar. I had taken the NGK wire off and replaced it with my known good OEM trail spare to ensure a good lead and connection. What I failed to do was clean out the connection where the lead goes into the coil. So while we did have spark (we were seeing that in our tester on three different plugs, and I shocked myself for good measure ), when coupled with some dirty and fouled plugs, it just wasn't enough to get the combustion going. Testing the coil today (it was good), I noticed how much dirt and oil was in the connector. Once we shot the coil connector with some brake cleaner and cleaned a few plugs, it fired on the first bump of the key.

On my first day troubleshooting we kept getting a smell of fuel when we tried to start. I think the engine was flooding and the OP has a known bad EVAP canister. So I think the EVAP canister was overwhelmed. I "think" the VSV should stop that, but perhaps that's bad.

Thanks to all who offered suggestions. I've been driving my 80 over 15 years, but honestly never had to troubleshoot anything other than starter contacts. Just PM stuff. I learned a lot going through the ideas of the posters. Thanks again for the help.