Truck will not idle after fan belt swap, please help...

[Boxcuta]

Good evening folks,

This is my first post, I've been lurking for a while now. I've searched and come up empty on my strange problem.

Yesterday I swapped out the fan belts. When I tried to go to work this morning, I drove a few blocks to the stop sign, while siting there the truck just died. I started it up again, ran for a few second them died again. It seems to run if I give it some gas. I got home and adjusted the belts again, I thought I may have tightened them a little too much. This didn't help.

A buddy came over to check my work, didn't see any problems. He suggested we drive around for a while, encase the ecu reset "un-learned" proper idle. We took the truck out for about 30 mins on the country roads, it ran and drove fine as long as my foot was on the gas pedal. Soon as you take it off at a stop, the truck dies.

We checked the timing, hoses and fuses, everything seems to be alright. I am completely stumped, I have never had any issues with the Cruiser. One thing that is odd, if I turn the AC on the truck runs fine. Is there a way to adust the idle maybe? I really can't figure this one out...

Thanks for any suggestions.

 

[Offroads4x4]

You may want to check your air intake tube (air-filter to intake manifold) for cracks. This is a common problem with issues similar to your idle problems. It may be cracked allowing air to rush in at idle but suck itself closed when accelerating.

Wrap it in plastic wrap to encase it solid then drive it again to see if that helps.

Just a thought to check out that only cost time and plastic wrap.

 

[CruiseOrlando]

A little brake cleaner sprayed around the air intake & vacuum lines can also tell you if you have a leak. If the idle picks up, you've found your trouble spot.

 

[Boxcuta]

Thanks guys I will check both those, I still find it odd that these would manifest after a belt change. Must be bad luck.

 

[jlg32281]

It doesn't take much to crack an old brittle intake tube.

 

[IdahoDoug]

Did you LITERALLY do nothing but change belts. Didn't check the air filter, engine oil, etc? Nothing at all? Did you disconnect the battery as the FSM may suggest?

DougM

 

[RockDoc]

A little brake cleaner sprayed around the air intake & vacuum lines can also tell you if you have a leak. If the idle picks up, you've found your trouble spot.

DON'T use brake cleaner, use intake cleaner or the like. Brake cleaner + high heat (think combustion, exhaust manifold, welding, etc.) produces poisonous phosgene gas.

More info: https://forum.ih8mud.com/tools-fabrication/347253-welding-warning.html

 

[blkprj80]

I'm thinking no on the brake cleaner as well. Some will eat plastic and/or dry out rubber. I destroyed my poor torque converter bolt access cover a couple days ago. At least I thought it was the brake cleaner spray - the cover was all bubbly when I pulled it out. Before, it was covered in tons of grease, so I don't know how it looked for sure.

The last can of MAF sensor cleaner I had did say that it was safe on plastics. Nasty smelling stuff in any case. Use it outdoors.

Did you knock a plug wire off while you were swapping belts?

 

[js93cruiser]

DON'T use brake cleaner, use intake cleaner or the like. Brake cleaner + high heat (think combustion, exhaust manifold, welding, etc.) produces poisonous phosgene gas.

More info: https://forum.ih8mud.com/tools-fabrication/347253-welding-warning.html

That's not true anymore, old brake clean used chlorine, they have since taken out that ingredient, the stuff we use at work states on the front "non chlorinated" and I spray it on hot stuff all the time to clean off oil, grease etc...

 

[kidglove13]

As others have said about the intake tube but I would also check all of the little vacuum hoses that run around near the front top and make sure one did not get knocked off or is cracked

The symptoms do sound like either a cracked intake hose or some type of vacuum leak

 

[Boxcuta]

Did you LITERALLY do nothing but change belts. Didn't check the air filter, engine oil, etc? Nothing at all? Did you disconnect the battery as the FSM may suggest?

DougM

Sadly yes, that's all I had time for that day. I did disconnect the battery as well. I was careful not disturb anything but who knows...


So I went out this morning checked the air intake tube, also checked air filter, there were no cracks in it as far as I could tell. Air filter was also in good shape. I checked the hoses/vacuum lines. There was one on the right side of the engine that was loose. I was located under the intake manifold (I think, I'm still a newb when it comes to engines.) I will try to upload a pic later today. I adjusted the clip to make sure it was snug.

I started te truck up, it idled around 900 then settled to 6500. I though that was the problem fixed. I took it for a spin around the block, by the time I got home it was idling around 200 RPMs again....

 

[jamisobe]

Depending on the aftermarket belts you may have used there could be an issue with slippage. The Toyota belts are wider than most aftermarket belts and shaped differently in the groove. It's possible that you are getting slippage, but probably not enough to affect idle. Still worth checking.

You could check by putting the old belts back on to see if the problem goes away.

 

[Kernal]

What year/model/engine do you have? Did you wash off the engine or fill up with fuel just before the symptoms started?? Getting a check engine light? Can you post up a couple photos of your engine and the one hose that is/was loose (think you need 10 posts to add photos however).

 

[Boxcuta]

Morning guys,

Sorry for the long reply. Work has been a little crazy this weekend... I have not had much time to work on the cruiser, I plan on going through the engine bay on Tuesday to look for any leaks and such.

It's drive-able currently, I just have to keep the AC turned on. My cruiser is a 94 FZJ80 with the 6 cylinder engine.


Could it be telling me to do that diesel swap I have always wanted?

 

[fj4068]

It only takes a hairline crack to cause a noticeable vacuum leak from with the intake tube. It may be worth the time to remove it entirely, clean it off and gently flex it while closely examining. A common spot for cracks is between the ribs.

If this is the problem, filling the gaps with automotive silicone is one effective temporary repair.

If new is needed, Cruiserdan for OEM parts.

 

[T rex80]

Disconnecting the battery may be the source of your problem. Whenever i disconnect my battery and reconnect, my idle drops to a point where the engine stalls ( never did it when it was new, just in the last 5 or so years), i just use the hand throttle to bring up the idle and it will always resets itself after a couple of days. You could probably adjust the idle if you don't have a hand throttle then adjust it back when it resets.

 

[86tuning]

If it's due to the unlearning of the idle speed controller, the correct fix is to clean the throttle body with some efi cleaner or carburetor cleaner. Use an old toothbrush and scrub off the carbon buildup: the black gummy stuff

 

[neal0124]

I'm thinking no on the brake cleaner as well. Some will eat plastic and/or dry out rubber. I destroyed my poor torque converter bolt access cover a couple days ago. At least I thought it was the brake cleaner spray - the cover was all bubbly when I pulled it out. Before, it was covered in tons of grease, so I don't know how it looked for sure.

The last can of MAF sensor cleaner I had did say that it was safe on plastics. Nasty smelling stuff in any case. Use it outdoors.

Did you knock a plug wire off while you were swapping belts?

The brake cleaner didn't affect the converter access cover. Mine is just like yours. It's subjected to a lot of sustained heat and is made of plastic.