1997 - cold uphill quirk

[Joenetworkpro]

Hello great gods of 80 series! I have an odd issue that I would like to sort out.

My 1997 40th has 232k miles and has been a champ.

I just moved, and my neighborhood now has a pretty good 1/4 mile hill to go up to reach the top. When the cruiser is cold and I start up the hill it will lag a little when it shifts, like its not getting fuel. If i press the accelerator hard it moves just fine. This only happens when it is cold. I've let it warm up and I don't see this issue at all. I have remote start, so warming it up isn't a big deal but id really like to figure this out.

The truck runs and drives perfectly in all other scenarios.

What do you guys think?

Any help is greatly appreciated!

 

[JACOBYWESTERN]

Does the lag occur when the transmission shifts between all gears?

 

[Joenetworkpro]

No. Only from first to second and when engine temp is cold. It's odd cause it shifts fine its just after shift I lose power until I punch it a bit then its fine.

When I do that I go above our posted speed limit. In a covenant HOA neighborhood that's not looked highly upon. Lol

When the engine is cold and I'm leaving a flat location this problem doesn't exist. Only when its cold going up my neighborhood hill. Bizzare for sure.

 

[1morebike]

Same problem here, we have a steep hill pretty much at the end of our driveway, when my truck is cold it seems to hate the hill unless I really get on it.

 

[Joenetworkpro]

Im guessing that, like my 97, if you let it warm up for a minute it does just fine?

 

[ShaneD]

I have a very similar problem on my 96, although its noticeable even on a flat road. I have an ultra gauge obdii display on mine and the problem seems to happen right when the engine goes to closed loop lambda control, so I have suspected that maybe the sensors are getting worn and are slow to respond. It hasn't bothered me enough to replace them yet, so I can't say for sure that is the issue.

 

[Joenetworkpro]

Which sensors do you think are needing to be replaced?

 

[ShaneD]

Sorry- the lambda/oxygen sensors. That's just my speculation based on what I see on the ultra gauge, I'm not sure that's the issue but I was going to start there.

 

[1morebike]

Yeah once it warms up its better. I'm thinking mine is kickdown cable and I just need to adjust it.

 

[Joenetworkpro]

Look what I found: https://forum.ih8mud.com/80-series-tech/537618-1997-fzj80-stalling.html

Gives us some places to start.

I've got a PM in to him for resolution.

 

[Joenetworkpro]

No response to PM. Any luck guys?

 

[ShaneD]

I'm out of town without my truck, so I can't try anything. As soon as I get back ill check my air intake boot for cracks as the other thread suggests. I wonder if I can unplug the oxygen sensor and drive out of the neighborhood to test that idea.

 

[Joenetworkpro]

You may throw a code but it is worth a shot. I inspected my intake tube that I replaced 80k ago and it looks fine. The fuel filter has never been changed. It has 232k on it. That could be where my problem is at. Let me know what you figure out. My 02 sensors have 232k on them as well.

 

[Joenetworkpro]

New Fuel Filter = Problem solved.

 

[nukegoat]

Yeah, i was going to comment that o2 sensors wouldn't make sense - i believe it runs in open loop mode until it warms up