3fe surge/ sputter

[Nick80]

Hey guyssss, I’ve been looking for a thread for the last few months that’s close to the symptoms I’m having but I can’t find one. So! I’m making one.
Out of the 4 vehicles I have right now, my Toyota is the least reliable haha. It also get the most attention.
The problem is (as best as I can describe it) a sputter and surge before cutting out completely.
It’s completely random. It can happen on acceleration, while at consistent speed, or dead stopped at a light.
Most of the time it will just restart. Other times it won’t restart right away. Some times it will happen 10-15 times while driving other times, it will happen once an be fine the rest of the day.
The thing I have noticed is that it has started happening more. Multiple times in a drive (again, some drives it happens a lot and some less). Now, she starts in the morning with no problems at all and will warm up and idol fine. It’s when you start driving.
THINGS IVE DONE
I’ve checked fuel pressure at idol and woth some rpm and it’s within spec. I can’t see while I’m driving and I haven’t been able to recreate the problem in the driveway.
I’ve checked the fuel relay and the efi relays and replaced both with known good relays.
I pulled the entire intake system off including the TB and checked for a leak. Nothing was found. The TB got a good clean and a new gasket.
The AFM looks like it might have been tampered with at one point due to some silicone on the black cap on top although I’ve seen this on many older yotas.
I did clean the AFM gently and made sure it’s free moving without taking it apart.
So at this point it could be lots of things still. No codes have been thrown. Anyone have things to check? Does this sound familiar to anyone?
Let me know!
Thanks!! I
Nick80

 

[Marco Lau]

I think you might have mentioned it in your OP.

"The AFM looks like it might have been tampered with at one point due to some silicone on the black cap on top"
I would start there.

 

[Nick80]

I think you might have mentioned it in your OP.

"The AFM looks like it might have been tampered with at one point due to some silicone on the black cap on top"
I would start there.

Expensiveeeee even for an old one haha. Any suggestions? Get a known good old one or do the maf conversion?

 

[jonheld]

When it doesn't restart after stalling, is the check engine light on with the key in the ON position before you crank the starter?
No CEL = no start

Have you replaced the set of 3 fusible links off the positive battery terminal?
They're known to become intermittent.

 

[Nick80]

When it doesn't restart after stalling, is the check engine light on with the key in the ON position before you crank the starter?
No CEL = no start

Have you replaced the set of 3 fusible links off the positive battery terminal?
They're known to become intermittent.

I’ll have to check that! And no I haven’t replaced much of that stuff. I’ve got everything to do it. I will and report back!

 

[Nick80]

FIXED!
Well, ladies and gentlemen, after going through almost everything I can think of, from fusible links to air Plenum to throttlebody and fuel pump to efi and fuel pump circuits. I have finally figured out what was causing my Land Cruiser to be the most UNRELIABLE vehicle that I own.
The airflow meter on these Toyotas are known to be pesky and can throw fault codes and cause issues without throwing fault codes. Plenty of forums talk about this particular early measuring system. In my case, the meter is in good working order, which I started to have my questions and doubts about. As I was replacing a couple fusible links and checking a couple of the other ones with the vehicle, running to see if there were any inconsistencies, I bumped the connector to the airflow meter and the vehicle sputtered then died instantly. When I say, I bumped, it was a very slight tap hardly noticed it on my sleeve kind of bump. I repeated this test multiple times and the vehicle would sputter and die and have a hard time restarting, unless I slightly lifted the connector. Overtime, the rubber gasket on the inside of that connector gets dry and cracked, and the purchase on the clips themselves holding the connector to the main body of the meter, starts to get loose. To prove my theory that this was in fact, my problem, I added some electrical tape to the outside of the connector to take up a little bit of extra gap, added a very small amount of dielectric grease, and then zip tied the connector in and slightly up. I’ve been driving the vehicle around with zero issues.(knock on wood.) for a few days now. My problem used to show at least once every single drive. I am confident this issue is solved and a new connector is on the way from the dealer right now. I hope this helps a few people out!

 

[Marco Lau]

FIXED!
Well, ladies and gentlemen, after going through almost everything I can think of, from fusible links to air Plenum to throttlebody and fuel pump to efi and fuel pump circuits. I have finally figured out what was causing my Land Cruiser to be the most UNRELIABLE vehicle that I own.
The airflow meter on these Toyotas are known to be pesky and can throw fault codes and cause issues without throwing fault codes. Plenty of forums talk about this particular early measuring system. In my case, the meter is in good working order, which I started to have my questions and doubts about. As I was replacing a couple fusible links and checking a couple of the other ones with the vehicle, running to see if there were any inconsistencies, I bumped the connector to the airflow meter and the vehicle sputtered then died instantly. When I say, I bumped, it was a very slight tap hardly noticed it on my sleeve kind of bump. I repeated this test multiple times and the vehicle would sputter and die and have a hard time restarting, unless I slightly lifted the connector. Overtime, the rubber gasket on the inside of that connector gets dry and cracked, and the purchase on the clips themselves holding the connector to the main body of the meter, starts to get loose. To prove my theory that this was in fact, my problem, I added some electrical tape to the outside of the connector to take up a little bit of extra gap, added a very small amount of dielectric grease, and then zip tied the connector in and slightly up. I’ve been driving the vehicle around with zero issues.(knock on wood.) for a few days now. My problem used to show at least once every single drive. I am confident this issue is solved and a new connector is on the way from the dealer right now. I hope this helps a few people out!

I think you might have mentioned it in your OP.

"The AFM looks like it might have been tampered with at one point due to some silicone on the black cap on top"
I would start there.

BINGO!!! congrats..