I have 286K on my 93 240 wagon and see no reason why it couldn't go considerably longer before it expires. The problem I am having with the car developed recently and is exacerbated by the cold weather. The car starts just fine every morning, but as it is about half way to operating temperature (which occurs about a mile from my house if I drive it right away) the engine begins to stumble. I pull into a parking lot or side of the road as soon as the symptoms appear. The car will eventually die out unless I continually pump the accelerator pedal. After several minutes of keeping it running this way, It will reach a desired temperature and run great again. I'm stumped. Any Ideas???

I would give a close look into the computers Engine Coolant Sensor. It could be the connector, the wiring or it could be lazy, if that even could be?

This guy is located on the head under the third intake runner.

The sensor changes its resistance as the temperature changes to tell the ECU at what stage of transition the engine is operating under.

The next thing might be the throttle position switch. This depends on your type of LH system. A 2.4 or a 3.0 as there are two types of TPS's.

Phil

thanks for the response. I will give both of these items a look at this weekend. The temp sensor makes sense to me. I don't understand how the throttle position sensor might fit into the equation being that the problem seems to be tempature dependent, but I will give it a look see anyhow.
thanks again for your response

Hi

You may be correct in your thinking about the TPS not having anything to do with the car stumbling while driving. One would not think that a dirty throttle throat would effect idle as much as it does either but it will.

It will affect the vacuum pull on the FPR of which, controls extra fuel pressure under accelerations. Check that hose to it as well for gasoline. If it leaks gas into the throttle bore the engine will have to burn it off.
In other words, the stumble is called a flat spot of power, until the engine get its cylinders good and hot.

A bad FPR can be the first suspect in flooding or long cranks before starting after sitting.

I did mention that the LH 3.1 has a different TPS. It uses a resistance band and wiper to talk to the ECU. It is possible that there is a worn thin spot in the middle or at the stopping or idling point.
The LH 2.4 just clicks so it's quick to verify.

Since it stumbles in the driveway too, you should put all of these in the realms of "looky-see" maintenance inspections.

The hose behind AMM can also get a pin hole in its side. This will affect drivability and idles.
AMM's are pretty reliable to a point if you have a bad one it runs really bad.

If you wipe out the throttle bore you will have that hose off. Shine a light from the inside out using a tubular light source in a dark area of your play pen or garage. (:)

Enjoy getting to know a simple system and a easy to work on car.
Once you get things touched up, into good working order, these cars pay back nicely.

This site has just about every scenario covered. If not, you can find it or someone that has been down the road and has an reasonable clue or answer.

But it all still takes some sweat equity on the learning curve.

Phil

Do the easy and free stuff first, they are all part of preventative maintenance and should be done on a regular basis.
Dan

Also general maintenance:

Clean the throttle body
Clean the IAC

If LH 2.4 consider a spare "known good" AMM. These are sadly best tested to be "known good" when the warmest months are on us.

Finally, assuming it is an automatic, make absolutely sure you have sufficient transmission fluid. this can only be tested hot which means a minimum of 20 minutes stop and go driving. A leaky tailshaft seal can drop the transmission to a level it bogs the engine while cavitating until it warms enough.

thanks for your response.What exactly does IAC stand for? I will certainly look at these areas of concern this comming weekend. The car is an automatic, but the mid warm-up stumble happens even if the car is warming up in my driveway.

Idle air control...many threads on here about it but if you cannot find one check the FAQ's at the top of the page...it is the exact same procedure for a 240.