Rough idle and stuttering from 800 to 2000rpm (1 Viewer)

[Travish325]

I am having a very annoying issue with my FZJ80. When the truck first starts up the idle is ok but when I go to take off the truck will stutter and have no power from about 800-2000. The engine feels like it is stumbling with a huge misfire but after I get over about 2000 rpm it runs ok. Once it is warmed up this issue gets better but then the truck idles super rough and low, around 200ish rpms and I can feel it missing. I did have a big exhaust leak right off the manifold but I fixed that and it's still messing up. I also just did spark plugs, wires, and cap and rotor about 3k miles ago and it was running great after that until now. I have looked for vacuum leaks but I don't see anything obvious. Any ideas will be appreciated.

 

[stlbill]

Check the fuel filter sock and make sure its not clogged. I had a similar thing going on with mine and turned out to be rust in the tank clogging the sock.

 

[Travish325]

Check the fuel filter sock and make sure its not clogged. I had a similar thing going on with mine and turned out to be rust in the tank clogging the sock.

How do I do that? I've heard the fuel filter is hard to get to on these.

 

[flintknapper]

How do I do that? I've heard the fuel filter is hard to get to on these.

The 'fuel filter' is underneath the intake plenum and not too fun to get to, but fuel pump filter/sock is in the gas tank connected to the fuel pump itself. You can access it by removing the second row seats, lifting the carpet and then removing an access plate there.

But I doubt the 'sock' is your problem. If it were....you'd likely have fuel starvation at all engine rpm.

Check for vacuum leaks first, especially the air intake hose from the air filter to the throttle body.

 

[baggar11]

I had an injector die on me in a full open position. It was dumping way more fuel than needed, especially at idle. In higher rpms, wasn't noticable. Maybe take them out and get them inspected and cleaned.

 

[blkprj80]

Check your throttle position sensor too.

If you can feel it missing when it's warmed up, you should be throwing a misfire code. Is the CEL on?