A new month, a new problem.  Here's the full story:

Two days after replacing the mechanical fuel pump on my 87 samurai, I was driving home from work and a vacuum cap under the carb blew off and the car would not idle anymore.  During one of my many stalls on the way home, I was slowing down with the transmission and something just changed in the way it was driving.  The clutch felt like it was engagine a lot sooner than before and out of nowhere i was hearing a popping sound when ever the engine would wind down (or when it would wind up during braking while down-shifting).  It sounds like excess fuel is being burned off.  I didn't notice the wobbly engine until I got home and replaced the vacuum cap.  It only wobbles when it idles.

It doesn't really look like the engine is wobbling too much in the video, but trust me, it's very noticeable in the cab.  The whole car wobbles when idling but it disappears as soon as you give it some gas.
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Is my engine mis-firing? HALP!

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The popping noise at the end began as soon as the wobbling began.  Some guy in a parking lot said it sounds like it's mis-firing, and i'm thinking he's right, but i thought i'd check with you experts first!

I've got a few more questions also:







Thanks a million!!

The first pic is a brake line. Fix it. Cap off ALL the unused vacuum nipples. Then if it still idles ruff. You may have jumped timing.
 If so it's not an expensive or tuff fix. The belt and tension-er is less than $30 at NAPA auto parts.

The first pic is a brake line. Fix it. Cap off ALL the unused vacuum nipples. Then if it still idles ruff. You may have jumped timing.
 If so it's not an expensive or tuff fix. The belt and tension-er is less than $30 at NAPA auto parts.

Thanks man!  could you elaborate a little more on what it means to have "jumped timing"?  I think i know what you're getting at, but i'm not entirely familiar with the term and could really use further explination.

Also, do you know if NAPA stores have well-informed employees who wouldn't mind taking a look/listen to my engine to help me diagnose it?  I've been to several other auto parts stores in my area and they've just been packed with employees who don't know a freakin' thing  Honestly, 1 guy took 15 minutes to figure out which gastket sealant to use for the mechanical fuel pump!  arrrg!

edit: i replaced the spark plugs and the problem is still there.  it runs suprisingly well, but you can tell it's only got 3 cylinders going.  I'm going to try replacing the wires/cap/rotor and if that doesn't fix it, i guess it's on to the timing belt?  Let me know if i'm mistaken about anything please!

The Zuke runs a timing belt . When they get old they can stretch. When an engine jumps time, the belt will get so loose that it will jump a tooth or two , throwing the mechanical timing between the cam and crank off. The timing belt  and tension er should be changed every 70 -80,000 miles.
 I have no clue how well informed a Napa employee is going to be.
You should also adjust your valve lash every 10,000 miles....JMHO ...Boxcar...
PS: A manual is a good investment.....

The Zuke runs a timing belt . When they get old they can stretch. When an engine jumps time, the belt will get so loose that it will jump a tooth or two , throwing the mechanical timing between the cam and crank off. The timing belt  and tension er should be changed every 70 -80,000 miles.
 I have no clue how well informed a Napa employee is going to be.
You should also adjust your valve lash every 10,000 miles....JMHO ...Boxcar...
PS: A manual is a good investment.....

If the timing belt is loose, will i be able to tell just by looking at it?  I'm assuming the timing belt is just behind that plastic peice that says "suzuki" on the front of the engine.  Can the plastic cover be removed without removing the fan housing and fan?  And is removing the fan housing/fan a pretty simple job or does it require any specialized tools?

I really appretiate your patience with me.  I probably seem like i have no business tinkering with a classic 4x4, but i really do want to learn!

I downloaded a complete manual in a .pdf for my suki.  I'll def. consult it when i'm doing the fixes!  I just need help with diagnosing the issues.

I also bought a ton of vacuum caps to seal off all the open ends on the carb., but sadly that didn't fix the issue

ok i think this case is closed.  I put all new vacuum caps on every loose end of the carb and around it and tweek the throttle just a little bit and it seems to be running extremely smooth.

Someone told me that to check to see if all the spark plugs are firing, i should let it idle and pull the wires from the plugs 1 at a time.  If i pull a wire and the engine's timing doesn't change, then that piston isn't firing.  What i want to know is if this test can damage anything and if this test can actually tell me what I need to know.  It sounded a bit iffy to me, but i was desperate and tried it out and it seemed all pistons were firing correctly. 

All I did was increase the idle speed a bit by tightening a screw on the throttle.  Could this just be masking an actual problem?  For example a problem with the timing chain/belt? (87's use a chain right?).

Anywho.  Thanks again for the assistance!

All the 1.3l engines use a belt.  If you don't know when your belt was last swapped out, I would look at putting a new one on.  Record the mileage somewhere so you know when to replace it again.  Depending on your mileage you might also want to look at installing a new water pump.  While it may not be needed your torn into that area of the engine anyway and nothing is more annoying then replacing a timing belt then two months later taking it back off again to replace the water pump.

Pulling a spark plug won't damage anything, just makes your vehicle run a little rough until you put it back on. 

When you bumped up the idle, is it idling at 800 rpm's now or higher?  If you want to make sure your timing is set correctly  you should be able to borrow a timing light from your local auto store to check the timing advance.

Boxcar is right in that a manual is a good idea.  If nothing else, hit acksfaq.com and check out the FSM (Factory Service Manual) online.  I would recommend spending the money on a FSM to keep in the shop.  It's nice to have a paper copy to look things up on.

Would you suggest a newbie such as myself attempt to change the timing belt or should i look for some help?   My sami doesn't have a tackometer so i have no idea what rpm's my engine is idling at.  It sounds like it's idling a little too high now, but i have no frame of reference so i don't know

I'm pretty sure a new timing belt will be my next fix.  Do you know around how much i'll need to spend for all parts/tools?  Just looking for a ballpark figure here, i don't expect anyone to know exactly!