Mine did this and I found out it was the timing belt that needed to be changed.
id change the coolant temp sensor
I have same problem.
if you got an automatic depending on what gear it is you may need a 2800 or 3500 rpm stall in your torque converter call a transmission shop if that's it they will help you
it has a pass 2 key antitheft system.most likely cause would be the key lock in steering coulm
EGR Valve ans sensor went out at the same time. Replaced them and it's good to go.
Possibly a defective torque converter lock-up solenoid. Disconnect the solenoid and see if that cures the problem. If so replace the solenoid.
The most common reason for a vehicle to run rough when it is cold is bad spark plugs or bad spark plug wires. Change the spark plugs and spark plug wires.
check your fuel pump, it may be working fine, but have a loose valve in it. also check your fuel tank, an old trick to play on people is to drop lots of plastic tape in their tank, it stays forever & sucks down onto the fuel line, temporarily blocking it, the vehicle stalls, then after it sits, starts again.
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If the boat idles fine and revs fine in neutral in the water and idles fine on the trailer, however has no power when you stick it into drive and give it some throttle a common problem with some of these early Mercury V6's is in the stator. The only way to fix this is to replace the stator.
My 89 jeep Cherokee surges at idle and sometimes stalls but runs fine once you are going what could cause this?
Probably a bad idle air control valve.