Truck dies at low idle after sliders welded on

Hi!

I have a 2004 Tundra Limited with roughly 230k miles on it. It has been running great and is caught up on maintenance for its age.

I had some fabrication work done on the truck last week and had some sliders welded on. Really happy with how they turned out, but driving home from the shop when coasting to a stop or stopped at a light, the truck would go from around 500 RPM and drop to a stall. No CEL or any other lights. I could put it back in park and restart it. Happened a few times driving home and eventually I would put it into neutral when stopped and kept it about 1k RPM and didn't have any more problems.

I replace the alternator this last weekend thinking it might be the culprit and if not, due to the age and mileage it felt like a good idea anyway. After driving around for a bit, I was able to recreate the same problem and the truck died again.


I am going to clean the throttle body and MAF sensor when I get back from work in a couple of days, but it seems like those causing a problem right after being welded on would be a bit coincidental.

Are there any other sensors that could have been cooked from the welding that could be causing this issue? The battery was disconnected and the fabricator came well recommended by everyone I spoke to.

Also, pics of the news sliders because I am really excited about them.

 

What other fabrication work? There is a pretty fat harness that runs down the drivers side frame. Maybe the passenger as well, not sure. But, sounds electrical based on stated work and wire location.

 

It was only the sliders welded on at this point.

 

BTW, I hope my sliders look that good. All I can say, is what you know - if shit went south right after new work - that's a good indication. Get under your truck and trace all wires, looms from the brake lights forward. Look for burns or melts. If you don't find anything, even if you do, code scan. I hope someone else has more.

 

Sounds typical of any battery disconnect of a throttle-by-wire Toyota with a dirty throttle body. Let the idle relearn, or better yet, clean the throttle body, then let the throttle relearn.

Nothing to do with the welding. As much as I personally disagree with weld-on sliders.

 

Wheel & tire package looks great. Are those stealth customs F5 -10 offset?


Make sure the battery is connect and tight since it was disconnect. Also check for a loose ground

 

What @landphil had stated. This is most likely your problem, hopefully. After you clean your MAF & Throttle body take your truck on a 10 or 15 minute drive if it’s still idling lowish, the truck should slowly relearn the proper idle.

 

Joshua, does it stall after initial start up?

 

I had welding done to my frame on the driver's side. Both the fuel supply and return lines run along the frame on the inside. My welder pried them loose and mangled them out of the way, and then shoved them back afterward somewhat haphazardly. Luckily, there was no damage (bends/kinks, whatever), all I had to do was re-secure the lines (he f'd up all the clips).

Maybe your welder also had to good sense to move the lines (so as not to explode) but in doing so caused a kink or other obstruction affecting fuel delivery?

Your ECU will relearn rather quickly after being powered down. My Land Cruiser (same 2UZ engine) was in an auto body shop for ~5 weeks with the battery disconnected, and ultimately coated with auto body dust. When I picked it up it would start, but not idle. I drove home with one foot on the gas (to keep it at ~ 1500 RPM and not stall) and the other foot on the brake. Eventually it relearned and idled/ran correctly. I think a new air filter was part of the solution.

I've since learned that the frequency of engine starts/stops plays a role in how quickly the ECU relearns...more is better.

 

This explanation makes a lot of sense, I would give the TB and MAF a good cleaning when I get off work, reconnect the battery and go for a drive.

As for the weld on sliders, 1st gens don't have a lot of options when it comes to body armor, or really any upgrades

 

Not with the high idle after the initial start. Just while coasting while driving or at a stop with the low idle.

 

How you drove your Land Cruiser home was exactly how I drove home. I am hoping it is TB / MAF related and clears up with cleaning and relearning. I did a very quick look at the inside of the frame and did not notice any obviously burned or melted areas, but will do a more thorough check Wednesday when I am home again.

 

Thanks! Those are the wheels, with Toyo Open Country AT3 in 285/75r17

 

If welding on a car without disconnecting the battery, you can fry the battery, I'd check the battery

This second thing doesn't pertain to welding, but on my 2nd gen, my air filter had slid off my intake pipe and would cause the truck to die at idle, you might want to check that your (if you have the factory airbox) airbox top is properly locked on, and if you have a CAI, that the air filter is secured onto the pipe

 

Check and see if you can smell unburned gas and it will make you eyes burn if near the tailpipe, i had a jeep that would not cut the added fuel for the initial warm up and would not let the engine idle under a certain RPM after it warmed up. It was all due to a bad connection and was solved by taking apart every plug and adding a little dielectric to each plug especially the ECU.

 

When you F them up you can't unbolt them to fix them.

 

Hey everyone, I had a chance to work on my truck today and was able to resolve the problem. I took the throttle body off and gave it a good cleaning, I will post the video below of the process I followed. After cleaning the TB, I let the truck sit at high idle for a bit, and followed a procedure I came across on youtube (shown in many different videos) of getting the computer to relearn idle. I will post that video as well.

TB Cleaning

Idle Reset

Thanks for all the ideas and directions to look into for troubleshooting this problem!

 

And Another happy Tundra!

 

Unless you get Brute Force Fab and select the intermediate bolt kit...