Idle trouble and loss of power 80s series (1 Viewer)

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South Carolina
I used an old spark plug wire boot and held it to seal the number one cylinder with the spark plug removed while turning the motor by hand. You could see it sucking it in and then pushing it out on compression.
And I also lined up the mark on the harmonic balancer with the degrees markings on the front of the motor to find tdc.
 

ceylonfj40nut

Waiting for Barn Time
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Check to see if dizzy is positioned correctly. Pull it out and restab it per FSM.
 
Joined
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South Carolina
Check to see if dizzy is positioned correctly. Pull it out and restab it per FSM.
Done did it. About 12 times actually 😂. I did notice it’s either at 12 o clock (pointing straight up towards the plug) or 10 o clock. That’s all I can get it to do. The FSM shows it at about 11 ? I should take pics and post them to show what I’m trying to say.
 

SmokingRocks

I bought a Cruiser to keep miles off my Cruiser
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Colorado
have you pulled your engine codes..... Slow and steady wins the race when you are diagnosing.

Once you download the file (1994 FZJ80 FSM) and open it up start by going to thie "diagnosi" pdf. Follow this file path to get to there. C:\Users\rnelson\Downloads\1994FZJ80FSM.zip\LC FSM\Engine\Engine\Sfi System

This will tell you how to pull the check engine codes on your rig, start there and report back. Don't buy any more parts.
 

SmokingRocks

I bought a Cruiser to keep miles off my Cruiser
Joined
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Messages
3,432
Location
Colorado
damn, you're right. Always always always pull your check engine codes first. Never pass up the low hanging fruit.

Ah ok, let's crack our knuckles and dive in then...

What we know
  1. You've established your timing is set correctly (or at least within the tolerance which will allow the engine to run)
  2. We know you have spark because the engine will run momentarily
What we DON'T know
These bullet points have inspections or test associated with them. @Tjs23 when you reply with your findings please quote this part of the message and respond to each test separately. The more detailed and organized you are in explaining what you observed the faster we can help you solve this.
  1. Are your plug wires hooked up correctly
    • Verify that you spark plug wires are hooked up to the correct port on the distributor (I've swapped 2 & 5 by mistake and it ran like dog piss)
  2. Is there a massive vacuum leak
    • Physically remove and inspect the rubber intake hose for cracks, check all accessible vacuum lines, replace any & all that show signs of cracking
  3. Is the engine not receiving enough fuel?
    • For sustained operation the engine needs three things: 1) Fuel 2) Compression 3) Spark
      • Since we have eliminated spark as an issue and suspect that compression is fine (much more rare of an issue) then we need to check the fuel system.
        • Fast Check: Have a friend crank the engine while you spray starting fluid into the filter house (you need the AFM and rubber hose on and sealed to have any hope to keep the engine running). If the engine fires and continues to run while you are fogging the intake then your issue is Fuel delivery related.
      • There is a common culprit in the fuel system called the Fuel Pump Relay. When it starts to fail it causes weird symptoms. The fastest way to test for a faulty Fuel Pump Relay is to remove the relay and put a jumper wire between terminal 5 and terminal 3 then try to start the engine.
1971399
1971420

  • IF engine starts and runs REPLACE THE FUEL PUMP RELAY
  • IF there is no change proceedto the next step;
    • Check that fuel is being delivered to the fuel rail;
      1. Disconnect the Fuel Return Hose from the top of the fuel pressure regulator, connect a 3 ft or so length of rubber tubing and run it into a clear water bottle or container
        1971400
      2. Jump Terminal 3 of the Fuel Pressure Regulator connector with 12v directly from the battery (Hotwires fuel pump)
        1971414
        1971421
      3. IF fuel begins to fill in the bottle, your fuel pump is OK
      4. IF no fuel flows to the bottle we will need to trace this back to the tank.

This process will either confirm or eliminate the fuel system as an issue. If it turns out to not be an issue then we will quickly re-verify spark, if that is OK then we will test compression, if that is OK then we will test the AFM and so on and so on. Basically, I'm starting you at the Big Three; Spark, Fuel & Compression as 98% of the engine problems 80's owners see are related to one of those functions. If they all pass then we will dust off the advanced chapters of engine diagnostics.

Just remember one step at a time bud slow and steady will net results, we'll get 'er.
 
Last edited:
Joined
May 1, 2019
Messages
25
Location
South Carolina
damn, you're right. Always always always pull your check engine codes first. Never pass up the low hanging fruit.

Ah ok, let's crack our knuckles and dive in then...

What we know
  1. You've established your timing is set correctly (or at least within the tolerance which will allow the engine to run)
  2. We know you have spark because the engine will run momentarily
What we DON'T know
These bullet points have inspections or test associated with them. @Tjs23 when you reply with your findings please quote this part of the message and respond to each test separately. The more detailed and organized you are in explaining what you observed the faster we can help you solve this.
  1. Are your plug wires hooked up correctly
    • Verify that you spark plug wires are hooked up to the correct port on the distributor (I've swapped 2 & 5 by mistake and it ran like dog piss)
  2. Is there a massive vacuum leak
    • Physically remove and inspect the rubber intake hose for cracks, check all accessible vacuum lines, replace any & all that show signs of cracking
  3. Is the engine not receiving enough fuel?
    • For sustained operation the engine needs three things: 1) Fuel 2) Compression 3) Spark
      • Since we have eliminated spark as an issue and suspect that compression is fine (much more rare of an issue) then we need to check the fuel system.
        • Fast Check: Have a friend crank the engine while you spray starting fluid into the filter house (you need the AFM and rubber hose on and sealed to have any hope to keep the engine running). If the engine fires and continues to run while you are fogging the intake then your issue is Fuel delivery related.
      • There is a common culprit in the fuel system called the Fuel Pump Relay. When it starts to fail it causes weird symptoms. The fastest way to test for a faulty Fuel Pump Relay is to remove the relay and put a jumper wire between terminal 5 and terminal 3 then try to start the engine.

  • IF engine starts and runs REPLACE THE FUEL PUMP RELAY
  • IF there is no change proceedto the next step;
    • Check that fuel is being delivered to the fuel rail;
      1. Disconnect the Fuel Return Hose from the top of the fuel pressure regulator, connect a 3 ft or so length of rubber tubing and run it into a clear water bottle or container View attachment 1971400
      2. Jump Terminal 3 of the Fuel Pressure Regulator connector with 12v directly from the battery (Hotwires fuel pump)View attachment 1971414View attachment 1971421
      3. IF fuel begins to fill in the bottle, your fuel pump is OK
      4. IF no fuel flows to the bottle we will need to trace this back to the tank.
One step at a time bud, we'll nail it down.
 
Joined
May 1, 2019
Messages
25
Location
South Carolina
Ok, let me establish a few things before we go too far.
1) the truck was running poorly before I ever touched it. It would idle rough and have loss of power until I took it down the road a bit. Never had any indicator lights pop up on the dash.
2) I changed the plugs, wires, cap, rotor. This did not help. Idling even more rough and running more poorly. NGK plugs and Carquest wires (I know, I know)
3) I spent a substantial amount of time aligning the dizzy, thinking I had made a mistake there.
4) I have checked and rechecked the plug wires and the dizzy about 10 times.
5) I cannot get the vehicle to fire at all. The motor will turn but no fire now.
 

SmokingRocks

I bought a Cruiser to keep miles off my Cruiser
Joined
Oct 6, 2014
Messages
3,432
Location
Colorado
Do you want to fix this or not? I understand what you are saying, if you want to figure it out then you need to follow my previous post step by step. Otherwise, we are wasting time here and you should just take it to a mechanic that knows what he is doing.

Not trying to be a dick here but I spend a fair amount of time making a very easy to follow method to help you diagnose what's wrong, yet your response sounds like you've tried everything you care to and you are venting that it didn't work. Not surprising that firing the parts cannon at it didn't work, it's gotten me before too, now I know better and am trying to pass that along to you.

These engines are fairly simple don't let it overwhelm you. How do you eat an elephant? One f***ing bite at a time

So what's your choice from here? It's time to put up or shut up.
 
Last edited:
Joined
May 1, 2019
Messages
25
Location
South Carolina
this is what I’ve done so far.

1) I removed and triple checked the air intake hose for any cracks
2) I have cleaned the TB. I triple checked all vacuum hoses going to the TB.
damn, you're right. Always always always pull your check engine codes first. Never pass up the low hanging fruit.

Ah ok, let's crack our knuckles and dive in then...

What we know
  1. You've established your timing is set correctly (or at least within the tolerance which will allow the engine to run)
  2. We know you have spark because the engine will run momentarily
What we DON'T know
These bullet points have inspections or test associated with them. @Tjs23 when you reply with your findings please quote this part of the message and respond to each test separately. The more detailed and organized you are in explaining what you observed the faster we can help you solve this.
  1. Are your plug wires hooked up correctly
    • Verify that you spark plug wires are hooked up to the correct port on the distributor (I've swapped 2 & 5 by mistake and it ran like dog piss)
  2. Is there a massive vacuum leak
    • Physically remove and inspect the rubber intake hose for cracks, check all accessible vacuum lines, replace any & all that show signs of cracking
  3. Is the engine not receiving enough fuel?
    • For sustained operation the engine needs three things: 1) Fuel 2) Compression 3) Spark
      • Since we have eliminated spark as an issue and suspect that compression is fine (much more rare of an issue) then we need to check the fuel system.
        • Fast Check: Have a friend crank the engine while you spray starting fluid into the filter house (you need the AFM and rubber hose on and sealed to have any hope to keep the engine running). If the engine fires and continues to run while you are fogging the intake then your issue is Fuel delivery related.
      • There is a common culprit in the fuel system called the Fuel Pump Relay. When it starts to fail it causes weird symptoms. The fastest way to test for a faulty Fuel Pump Relay is to remove the relay and put a jumper wire between terminal 5 and terminal 3 then try to start the engine.

  • IF engine starts and runs REPLACE THE FUEL PUMP RELAY
  • IF there is no change proceedto the next step;
    • Check that fuel is being delivered to the fuel rail;
      1. Disconnect the Fuel Return Hose from the top of the fuel pressure regulator, connect a 3 ft or so length of rubber tubing and run it into a clear water bottle or container View attachment 1971400
      2. Jump Terminal 3 of the Fuel Pressure Regulator connector with 12v directly from the battery (Hotwires fuel pump)View attachment 1971414View attachment 1971421
      3. IF fuel begins to fill in the bottle, your fuel pump is OK
      4. IF no fuel flows to the bottle we will need to trace this back to the tank.

This process will either confirm or eliminate the fuel system as an issue. If it turns out to not be an issue then we will quickly re-verify spark, if that is OK then we will test compression, if that is OK then we will test the AFM and so on and so on. Basically, I'm starting you at the Big Three; Spark, Fuel & Compression as 98% of the engine problems 80's owners see are related to one of those functions. If they all pass then we will dust off the advanced chapters of engine diagnostics.

Just remember one step at a time bud slow and steady will net results, we'll get 'er.
 

SmokingRocks

I bought a Cruiser to keep miles off my Cruiser
Joined
Oct 6, 2014
Messages
3,432
Location
Colorado
this is what I’ve done so far.

1) I removed and triple checked the air intake hose for any cracks
2) I have cleaned the TB. I triple checked all vacuum hoses going to the TB.

Great. Well, what I can see is that you still haven't gone through the procedure I've laid out. Specifically #3.

If you truly want the help then please realize it's right in front of you. However, if checking the intake hose, adjusting the timing and cleaning the TB is as far as you care to go then it's time to seek a qualified mechanic. (Did you use a new OEM gasket when reinstalling the Throttle body?)

  1. Are your plug wires hooked up correctly
    • Verify that you spark plug wires are hooked up to the correct port on the distributor (I've swapped 2 & 5 by mistake and it ran like dog piss)
  2. Is there a massive vacuum leak
    • Physically remove and inspect the rubber intake hose for cracks, check all accessible vacuum lines including the brake booster line, replace any & all that show signs of cracking
  3. Is the engine not receiving enough fuel?
    • For sustained operation the engine needs three things: 1) Fuel 2) Compression 3) Spark
      • Since we have eliminated spark as an issue and suspect that compression is fine (much more rare of an issue) then we need to check the fuel system.
        • Fast Check: Have a friend crank the engine while you spray starting fluid into the filter house (you need the AFM and rubber hose on and sealed to have any hope to keep the engine running). If the engine fires and continues to run while you are fogging the intake then your issue is Fuel delivery related.
      • There is a common culprit in the fuel system called the Fuel Pump Relay. When it starts to fail it causes weird symptoms. The fastest way to test for a faulty Fuel Pump Relay is to remove the relay and put a jumper wire between terminal 5 and terminal 3 then try to start the engine.

  • IF engine starts and runs REPLACE THE FUEL PUMP RELAY
  • IF there is no change proceedto the next step;
    • Check that fuel is being delivered to the fuel rail;
      1. Disconnect the Fuel Return Hose from the top of the fuel pressure regulator, connect a 3 ft or so length of rubber tubing and run it into a clear water bottle or container View attachment 1971400
      2. Jump Terminal 3 of the Fuel Pressure Regulator connector with 12v directly from the battery (Hotwires fuel pump)View attachment 1971414View attachment 1971421
      3. IF fuel begins to fill in the bottle, your fuel pump is OK
      4. IF no fuel flows to the bottle we will need to trace this back to the tank.

This process will either confirm or eliminate the fuel system as an issue. If it turns out to not be an issue then we will quickly re-verify spark, if that is OK then we will test compression, if that is OK then we will test the AFM and so on and so on. Basically, I'm starting you at the Big Three; Spark, Fuel & Compression as 98% of the engine problems 80's owners see are related to one of those functions. If they all pass then we will dust off the advanced chapters of engine diagnostics.

Just remember one step at a time bud slow and steady will net results, we'll get 'er.
 
Last edited:

SmokingRocks

I bought a Cruiser to keep miles off my Cruiser
Joined
Oct 6, 2014
Messages
3,432
Location
Colorado
2) I changed the plugs, wires, cap, rotor. This did not help. Idling even more rough and running more poorly. NGK plugs and Carquest wires (I know, I know)

Get rid of the Carquest wires... Not joking, Denso's and NGK's are on rock auto for under $50. Everyone who has seriously done work to their 80 here has arrived at the same consensus that Land Cruisers regularly reject / will not work with non OEM parts in many applications.

Stick with OEM, denso, aisin, NGK or your headache will get worse.

Have you actually put a timing light on the engine yet??
 

SmokingRocks

I bought a Cruiser to keep miles off my Cruiser
Joined
Oct 6, 2014
Messages
3,432
Location
Colorado
so I decided to change the button, cap, plugs, and wires while I was at it. I hoped that new plugs and wires would help solve my problems. The plugs really needed changing. They were pretty corroded and fouled. I marked everything to try to get the timing back correct and installed the new parts. Now, the engine runs much worse. It has substantial loss of power and wont even idle without shutting off.


Your problem intensifies here after work you did. This means STOP and backtrack until you figure out the culprit. What brands did you use for the button and cap? just replacing those shouldn't affect the timing of the engine. Have you tried putting the old parts back on to see if it improves?

These are ancillary questions, you still need to follow the procedure I've outlined to move towards the fix as I am beginning to suspect that several unrelated issues at play.
 
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Messages
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Location
Olathe, KS, USA
Your problem intensifies here after work you did. This means STOP and backtrack until you figure out the culprit. What brands did you use for the button and cap? just replacing those shouldn't affect the timing of the engine. Have you tried putting the old parts back on to see if it improves?

These are ancillary questions, you still need to follow the procedure I've outlined to move towards the fix as I am beginning to suspect that several unrelated issues at play.

Did your list include: Do you have a CEL (Check Engine Light) with key on in "run" position, prior to engaging "start?"

If not, nothing will make it run, because the ECU isn't ready.

Check to make sure your CEL is not burned out.
 
Joined
May 1, 2019
Messages
25
Location
South Carolina
Do you want to fix this or not? I understand what you are saying, if you want to figure it out then you need to follow my previous post step by step. Otherwise, we are wasting time here and you should just take it to a mechanic that knows what he is doing.

Not trying to be a dick here but I spend a fair amount of time making a very easy to follow method to help you diagnose what's wrong, yet your response sounds like you've tried everything you care to and you are venting that it didn't work. Not surprising that firing the parts cannon at it didn't work, it's gotten me before too, now I know better and am trying to pass that along to you. These engines are fairly simple don't let it overwhelm you. How do you eat an elephant? One f***ing bite at a time

So what's your choice from here? It's time to put up or shut up.
[/
I plan on following your steps and I am truly thankful that you have spent the amount of time that you have sending me that information. I am more than willing to figure this out.

Btw, I have not pulled the trigger on the “parts canon”. I am listening to the wiser.

I won’t say another word until I’ve exhausted your step by step instructions.
 

SmokingRocks

I bought a Cruiser to keep miles off my Cruiser
Joined
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Messages
3,432
Location
Colorado
Good to hear it, if you stick to the program we'll be here to help you all the way.

Send me a private message if you have any questions, I truly want to help you get your cruiser back on the road again.
 
Joined
May 1, 2019
Messages
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Location
South Carolina
@SmokingRocks
1) I checked the spark plug wires and they are placed correctly
2) I have found no vacuum leaks. I inspected all the hoses I could find and found that all were supple and intact.
3) I checked the fuel pump relay carefully per the FSM. It checks out fine with ohmmeter.
1972049

I did not have anyone to help me this afternoon so I could not spray any starting fluid in the intake.
I put a jumper wire in the fuel relay plug. No change when I tried to crank.
I checked the fuel coming into the pressure regulator by jumping the fuel relay plug. We have fuel. It doesn’t shoot out with force. There is a steady stream.
 

ppc

M Go Blue
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I checked the fuel coming into the pressure regulator by jumping the fuel relay plug. We have fuel. It doesn’t shoot out with force. There is a steady stream.

The fuel comes into the fuel filter, out of filter to fuel rail close to the firewall. The fuel pressure regulator is at the opposite end of the fuel rail. The rubber fuel line attached to the regulator is the return line that goes back to the tank. The "steady stream" is just the excess fuel not consumed by the injectors and not necessary to maintain the proper fuel rail pressure.
 

SmokingRocks

I bought a Cruiser to keep miles off my Cruiser
Joined
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Messages
3,432
Location
Colorado
Hmmm ok so you presumably have fuel. This is a GOOD thing, it means we’ve just ruled out the fuel system as the issue. This narrows it down to no or incorrect timing of spark or no compression

Pull your engine codes, maybe something is lingering in there
 
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