01 LHS: Engine dies and then fires back up in 1 second

[fosterc]

While driving my 2001 LHS with 110k miles (anytime/anywhere) the engine will die: RPMs will fall, cruise control will turn off, and the warning tone will sound. If you are in motion (even 2 MPH) after less than a second, the engine will simply begin running again. If you are stopped, then the engine will die completely. A quick shift into neutral, prompt restart and back into drive will keep the honking horns behind you to a minimum if you are at a stoplight.
I have logged the events and there is no distinguishable pattern. Acceleration, cruise, braking, idle, warm, cold, early, late, full of gas, little gas, premium gas, whenever… doesn’t matter. There is no pattern in time either. The events can happen as close together as 4-5 seconds, or it may go 10 minutes. Rarely is it longer than 10 minutes.

The check engine light goes on when it happens and immediately goes off when the car begins running again. There were no codes stored in the OBDII system (except for a faulty key about 200 starts ago…)

After research, I began to suspect the camshaft and crankshaft sensors. Being uncertain however, I took it to a Five Star Dealership Service Center, where they (for $45) confirmed it was the camshaft and crankshaft sensors. After recovering from the nearly $500 quotation for repair (where they would credit my $45), I elected to change the $80 worth of sensors myself. All went smoothly, and sure enough after about 3 minutes on the road, it did it again; same symptoms as before.

I am suspicious of the faulty key code. I have an aftermarket alarm system installed with the remote start feature. The system comes with a chip mounted near the ignition switch to simulate the presence of the key. Occasionally, the remote start won’t work. This happens more frequently in extreme temps (especially when it is very cold and you want the darn thing to work). Right now in the Midwest, temps are very mild (highs in upper 70s and lows in mid 50s). I considered a failure of the alarm system’s starter kill, but when the alarm system kills the engine, the warning tone will not sound.

Could a failing ignition switch cause this? Somebody also suggested something in the throttle body. There, of course, is the possibility of the ECM. I am at a loss, and will appreciate any help I can get.

[robc45]

the crank sensor is not properly gaped. .03 to .07

[machineman]

I had a similar prob with a leBaron. Stemmed from disconnecting the distributer wire every night to theft proof it! Bad dist. wire would heat up and have too much resistance after long driving. Leave it an few minutes and it would start again. Might be a wire problem

[sub006]

Try puttting it in neutral at every stoplight. If you can keep revs around 700 it shouldn't stall. If it gets down around 500 rpm watch out.

[taillight]

It sounds like something id disconnerting. The remote start is the first thing I would disconnect.

[jwd_lhs]

After some searching on Google, it seems this is a commonly reported problem for the LHS. I had a similar issue today, but not while moving. While stopped at a light, the engine rev'd slightly while not touching the gas (cruise was off too). When I put it in park it reved up a bit more and then when I pulled it back into drive it died. It fired back up and went back to normal. This car was bought used and is at 101,767 miles now.

I had an issue on my Jeep Wrangler where it would die suddenly (all electrical) while driving. After pulling over and waiting about 5 min. it would crank back up and run for fine for a few weeks. All of my sensors were fine, crank sensor and neutral safety were working, it turned out to be a faulty safety cut-off relay in the underhood fuse block. I swapped it with my headlamp relay since they were the same type and problem went away. I replaced both of them right after that and no problems since.

I'm buying a Haynes or Chilton's manual for this car since I'm not familiar with it yet.