98 Ls400 Strong Shake When Cold Out

[mades32388]

Hello,

I've had my '98 LS400 for 5 years now (love it).

It seems when it's cold out and I first start driving the car will have a strong shake - it's not usually consistant and sometimes doesn't even happen (usually it does at least a little shake) -- once the car has been driven for a few minutes the "shaking" goes away.

I kinda feel like it's a throttle issue but would love to have suggestions in specific.

This issue started last winter on cold days but once the spring came and weather was warmer the problem went away........I didn't have one single issue for the entire spring/summer season. Now that it's getting cold - the issue came back on cold days. Thing is I can't always duplicate the problem.

Also, the car doesn't seem to idle any higher or lower than normal (that I can tell) and otherwise drives perfectly (no slipping of gears or any other issues).

Thanks,

[McSwine]

My 2000 would shake a little on cold mornings; it was most noticeable right after startup while sitting in the driveway. I replaced my transmission mount and the problem went away.

[mades32388]

The issue for me doesn't occur while standing still. Only when driving.

Any other thoughts??

[cardona6569]

If you have not changed the tranny mount have it checked, it is most likely toasted by the heat at this time. I would also check for a spark misfire and change fuel filter also.

[IS400]

If you have not changed the tranny mount have it checked, it is most likely toasted by the heat at this time. I would also check for a spark misfire and change fuel filter also.

These are supposed to be life time fuel filters. How cold does it get in Puerto Rico? 68? LOL!

A good one to check it dragging brakes when it is cold, especially if you use the parking brake. The cable can fail to retract all the way, especially if you use it infrequently. Just and idea, but good luck!

[eatingupblacktop]

Could be the cold start circuit. Could also be a cyl getting a weak spark under load (HT wires) or an injector sticking until it warms up enough.

[MR. LEX]

Try to check your motor mounts they wear out after awhile.