Topic: Not running good when cold

[sharpxmen]

Sharp,

I will need to get a volt meter.  I was in constuction before, my auto tools are limited to wrenches and sockets mostly...

you should have one anyway, it's about $10 for a digital one which would do the job

as far as the plugs go, what gap are you running there, seems a bit big (from the picture)

[k]

you should have one anyway, it's about $10 for a digital one which would do the job

as far as the plugs go, what gap are you running there, seems a bit big (from the picture)

.050 t0 .055    Jacobs recommended up to .065 when I installed the system years ago.  Never had a problem with it and the old plugs have been in the Jeep since 2003 or longer... too bad Jacobs isn't around anymore, though I am hearing good things about Performance Distributors.  You just don't want to shock yourself.

[k]

wow 3 of them look like they got way to hot. discolored and warped ends

try the old plugs again maybe you got bad ones

might not have gotten the right ones either...  supposed to use plain copper plugs; the system is too hot for plantiums or iridiums.  These might not have been just copper...

[k]

try this (PCM temp sensor is on the thermostat housing)

came up with 1300 - 1315, which I guess checks out as I have a 180* thermostat.  Might change it out back to stock temp though.  Also, replaced the cap with one that has brass terminals (old one was aliuminum and showed some weird wear patterns), and a new rotor to go with it.  Seams to run a lot better.  I will let it cool down again and take it out in the morning.

[sharpxmen]

came up with 1300 - 1315, which I guess checks out as I have a 180* thermostat.  Might change it out back to stock temp though.  Also, replaced the cap with one that has brass terminals (old one was aliuminum and showed some weird wear patterns), and a new rotor to go with it.  Seams to run a lot better.  I will let it cool down again and take it out in the morning.

you should check the impedance at cold as well (or at the engine temperature you experience the issue - that's where you want to make sure is within specs).

[k]

K.I.S.S. principle was in effect.  No. 3 plug looked worse than the rest when I did a compression check, so I popped the cap and had a look in there.  Both the # 3 terminal an rotor were heavily pitted.  A new cap and rotor later, and we are running strong again.  Think I found the core of the problem, versus trying to fix all the symtoms that kept popping up.   Thanks for the ideas and help!

[sharpxmen]

glad you figured it out but

[k]

glad you figured it out but

but?  That sounds like a loaded statement

[sharpxmen]

but?  That sounds like a loaded statement

hmm, 1/2 my post went away

It should have read - but this sounds like something that should have been "visible" when warm as well, hope there's nothing else hidden.

[k]

hmm, 1/2 my post went away

It should have read - but this sounds like something that should have been "visible" when warm as well, hope there's nothing else hidden.

The old cap had aluminum terminals.  From what I know of aluminum, it can expand and contract a bit as it heats and cools.  Once warm, it might have been just enough for the Jacobs Ignition to still jump the gap, which would also explain part of the loss of power once it did warm up.  (it wasn't backfiring or spitting once warm, but you could notice a loss of power.)  I will just have to keep an eye on it for now.