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Cold Idle Problem

Hello group,

I've got a '99 XJ 4.0 Auto with just shy of 100k mi. that's developed a problem lately. I've googled all the idle problem links and have done all the T-Body cleaning steps to no avail.

So, here's the problem: Cold starts on cold mornings, slow to crank, stumbles at first, then with a blip of the gas pedal it flattens out and idles fine, remove my foot and it stalls. Start again, it'll crank for a while, and I'll hold it WOT and it'll fire with a strong gas smell. Drive it for a few minutes and it'll smooth out and be fine until it sits again in the cold.

I bought a set of plugs, wires, air filter, rotor and cap to see if that'll help too. I also had my battery tested and it showed that it needed to be replaced, which I'll get to this weekend.

I guess, the questions lies in the idle problem, could it be solved with the battery and tune? Is it likely to be something like the two sensor plugs that are bolted to the TB?

Thanks in advance for all your help!

Josh

Reply to
Josh
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I gather you haven't installed the ignition components yet. They may help.

Earle

Reply to
Earle Horton

That could be the connection on the TPS. I clean the connections on my throttle body with a spray contact cleaner every couple years when it starts doing things like you describe. The best is an electronic cleaner, but WD40 will do in a pinch.

They also don't like low batteries. If it comes back and holds for the day, then I usually suspect the battery cable connections are dirty. This prevents a full charge from getting into the battery.

Mike

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

It sounds like the idle air motor which is one of the things attached to the throttle body.

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Reply to
billy ray

I was thinking that too, but he states he cleaned everything.

Mike

billy ray wrote:

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Reply to
Mike Romain

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