FZJ80 Cranks, No Start after HG Replacement (1 Viewer)

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Nov 16, 2020
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Hi all -

I'd be deeply grateful for sage advice. After completing a head gasket replacement on my 1997 LX450, the engine turns over and sounds like it is about to start (machine gun sound) but never actually starts. It last started about five months ago. I've tried searching for similar issues so I have listed the symptoms below.

CEL ON
Fan turns slowly
New Diehard Gold Battery (tested)
New Denso Spark Plugs
Reman Sequoia alternator (photoman upgrade)
Reman Denso starter (tested)
Red Battery light on
Fuel comes out of fuel return line
Removing gas cap doesn't lead to any hissing sound (i failed to de-pressurize before beginning the HG job)
Throttle intake won't open so starter fluid doesn't help

I've also attached a photo and a video.

Any advice on where I should turn to next? Many, many thanks.
IMG_20210914_183043.jpg


 
Hi all -

I'd be deeply grateful for sage advice. After completing a head gasket replacement on my 1997 LX450, the engine turns over and sounds like it is about to start (machine gun sound) but never actually starts. It last started about five months ago. I've tried searching for similar issues so I have listed the symptoms below.

CEL ON
Fan turns slowly
New Diehard Gold Battery (tested)
New Denso Spark Plugs
Reman Sequoia alternator (photoman upgrade)
Reman Denso starter (tested)
Red Battery light on
Fuel comes out of fuel return line
Removing gas cap doesn't lead to any hissing sound (i failed to de-pressurize before beginning the HG job)
Throttle intake won't open so starter fluid doesn't help

I've also attached a photo and a video.

Any advice on where I should turn to next? Many, many thanks.
View attachment 2786475


In your video, the CEL is ouot of view. Is the CEL light on when the key is turned to the RUN position? If not, then the ECM is not in a state to allow it. You MUST track down why.

Could be MANY things, but lets start there.
 
Your battery may test fine, but does it have enough charge to actually start the truck? Is the distributor in the correct alignment?
 
In your video, the CEL is ouot of view. Is the CEL light on when the key is turned to the RUN position? If not, then the ECM is not in a state to allow it. You MUST track down why.

Could be MANY things, but lets start there.
Many thanks for the quick response.

Yes, the CEL light is on when the key is turned to the run position.

 
Your battery may test fine, but does it have enough charge to actually start the truck? Is the distributor in the correct alignment?
That was my concern, as well. I had this issue with the Yellow Top that was last in the truck and I thought it was too depleted.

I bought the Diehard Gold battery today from Advanced Auto Parts, had it tested before I accepted it, and put it in the truck this afternoon. It was manufactured in July 2021.
 
Your battery may test fine, but does it have enough charge to actually start the truck? Is the distributor in the correct alignment?
The distributor rotor was set facing the first spark plug at the 1pm position with the engine at top dead center. I have seen others place it toward the 11am position. Should I adjust it?
 
The distributor rotor was set facing the first spark plug at the 1pm position with the engine at top dead center. I have seen others place it toward the 11am position. Should I adjust it?


Yes, that's most likely why it won't start. You are one tooth off. It should be about the 10:00-11:00 area. Mine was a little short of 11:00.

You will have to set at TDC, remove distributor and reinsert until correct.
 
Yes, that's most likely why it won't start. You are one tooth off. It should be about the 10:00-11:00 area. Mine was a little short of 11:00.

You will have to set at TDC, remove distributor and reinsert until correct.
Thank you - I will try that and report back.
 
I marked this gear with blue paint on mine when the marks on the shaft align. This gear is two teeth over when in the correct position. This photo is actually one tooth on the shaft off (corresponding to 4 teeth on the smaller gear.0
20210517_150208.jpg
 
As stated above be sure your CEL is on when the key is turned to the on position.

Your lights will come on (and some go off as below).






Next, when cranking the engine (for 4-5 seconds) you should see a small amount of tach needle 'bounce' if current is going from your igniter to the distributor. NOT SEEING THAT ON YOURS. Check connections at dizzy and igniter.




Your distributor could be 'off' a tooth or two or even 180° out....but we need to establish the other two things first if you don't hear it trying to fire.
 
Thanks, all. I've adjusted the distributor rotor as noted and it now starts! However...

It immediately goes to 3000 RPM with slight smoke coming out of the passenger firewall side. Video below...

 
Last edited:
Thanks, all. I've adjusted the distributor rotor as noted and it now starts! However...

It immediately goes to 3000 RPM with slight smoke coming out of the passenger firewall side. Video below...


Is your throttle cable adjusted within spec?
 
Is your throttle cable adjusted within spec?
Excellent point. It was not. I've adjusted the cable. After the first start up, I received engine misfire codes P0300, P0301, P0302, and P0304. I cleared the codes and turned off the car.

After the next start, the codes did not come back. However, there was a very rough idle with the truck vibrating until it stalled.

I've already replaced the fuel filter, fuel pressure regulator, and had the fuel injectors cleaned, so I'm not sure what it could be. Thank you again for all the help - unfortunately, I'm at a loss.

 
Excellent point. It was not. I've adjusted the cable. After the first start up, I received engine misfire codes P0300, P0301, P0302, and P0304. I cleared the codes and turned off the car.

After the next start, the codes did not come back. However, there was a very rough idle with the truck vibrating until it stalled.

I've already replaced the fuel filter, fuel pressure regulator, and had the fuel injectors cleaned, so I'm not sure what it could be. Thank you again for all the help - unfortunately, I'm at a loss.


Remember, your battery was disconnected. It has to "relearn" so it will cycle through some of its settings during the first minute op operation. Let it run a bit and do this 3-4 times to see if it fixes itself.
 
Also, have you set your timing?
 
Remember, your battery was disconnected. It has to "relearn" so it will cycle through some of its settings during the first minute op operation. Let it run a bit and do this 3-4 times to see if it fixes itself.
Thank you. I've now run it for a bit and no more engine codes and it no longer stalls. However, it runs very, very rough and RPM goes up and down below 1000rpm. It's so rough that the actual engine shakes...

 
Thank you. I've now run it for a bit and no more engine codes and it no longer stalls. However, it runs very, very rough and RPM goes up and down below 1000rpm. It's so rough that the actual engine shakes...


Check your plug wires to make sure they are on the proper cylinder in the proper order.

Check to make sure you have on all your vacuum hoses. That acts like a massive vacuum leak.
 
Check your plug wires to make sure they are on the proper cylinder in the proper order.

Check to make sure you have on all your vacuum hoses. That acts like a massive vacuum leak.

Thank you - honestly, I wouldn't be surprised. I foolishly rushed through putting back together the upper plenum. I'll re-do that part and report back. Greatly appreciate it.
 

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