Spark Plug Gaping
draggon58368
11-07-2004, 01:13 PM
Alright guys I did a search for spark plug and gap together and sepratly and came up with nothing. I am doing my first tune up on this My 88 cherokee since I bought it and I don't have a haynes or chiltons. My next resource is always a fourm of somekind. So who can point me in the right direction for the gap on my 4.0? I am going to go and finish up the oil change and AMP install I will be back to check in an hour or so.
rotorfloat
11-07-2004, 02:07 PM
The specs should be on the underside of the hood, on the right hand side (this may be peculiar to canadian vehicles though...).
At any rate, the gap is .035"
An old mechanic told me that engines idle smoother if you increase the gap just a 'smidgen'. I run at about .040", but I don't notice anything from .035"
On my old comanche, I pulled the stock coil and installed an Accel 'Super Coil' (well, if it says super, it must be good..), along with cap and rotor, platinum plugs. With that setup I was gapping at about .060" with great throttle response and more pull at low rpms. I got greedy and upped the gap to .080", but the contacts in the cap burned away after about 6 months, leaving me stranded one day. A new cap and back to 60 thou and it lasted me until 'retirement' (crusher).
At any rate, the gap is .035"
An old mechanic told me that engines idle smoother if you increase the gap just a 'smidgen'. I run at about .040", but I don't notice anything from .035"
On my old comanche, I pulled the stock coil and installed an Accel 'Super Coil' (well, if it says super, it must be good..), along with cap and rotor, platinum plugs. With that setup I was gapping at about .060" with great throttle response and more pull at low rpms. I got greedy and upped the gap to .080", but the contacts in the cap burned away after about 6 months, leaving me stranded one day. A new cap and back to 60 thou and it lasted me until 'retirement' (crusher).
Automotive Network, Inc., Copyright ©2026