84 CJ7 Rough Idle

May 10, 2006 5 Replies

OK! I know everyone is thinking idle tubes...but wait!



Here is what is happening:



Had a coolant leak and it was a busted head bolt. Got that problem fix and then did the Nutter bypass. All was well and good for 2 weeks. Then all of the sudden it started to miss.



I noticed that the distributor was never tightened back down after the bypass (it was 'tight' but it wasnt 'tight'). So I grabbed the handy-dandy timing light to reset the timing hoping the timing had slipped.



Put on the timing light and no light. Thought maybe the light went kaput so I borrowed a buddies. Again, nothing. I had checked #1 plug for spark just a day previous, and there was spark...but not a lot. Took the coil to be tested. All within spec. Distributor was recently replaced as were wires & plugs. Wires all test ok. Removed all plugs and cleaned them.



I was thinking that it may be ignition module blew after the nutter bypass. Any way to check...or any other ideas to pursue?



PK



LOL!

If you check # 2 it also will maybe only flicker and you might get a light on #3.

That is a classic symptom of those freakin idle tubes!

I chased the whole freaking ignition system on an 85 a couple years ago for that exact thing.

The clip on timing lights won't see the signal on the bad or no spark on

1, 2 and maybe 3 because the idle tube that feeds those is blocked. I know the carb is sideways, but the two barrels on the carb like to feed a half an engine each.

Mike

86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail >

I checked the m*********on valve too inside the spark plug plumbing. It was stuck too.

Yes.....

Damn near drove me nuts. I swapped everything including distributors. It was also a couple weeks after a carb clean. Some more junk was hiding.

It was a thread I started a couple years back on this group on an 85 with strange spark.

The engine was idle running on 3 1/2 cylinders.

Mike

pkaser wrote:

Join the Discussion

Have something to add? Share your thoughts — no account required.

Didn't find your answer?

Ask the community — no account required