1986 v6 auto.Have no fuel to start car, traced it to bad ecm.Order new one from Advance auto Cardone 77-7170. Car starts and runs.But at a stop light car will idle down then stall and die.Also after installing new ecm car shifts hard and lacks power then accelerating. Have changed idle air value. No differance.Need help

Does the engine high idle when first started? If not you might still have an issue with the IAC. If the engine high idles when started and slows down when warm the IAC is working.

Did you use the chip from your old ECM in the new one? If not it's worth a try. Disconnect the battery when doing it.

MAKE VERY SURE the notch in the ECM chip stays pointing in the same direction as the old one

[This message has been edited by phonedawgz (edited 12-29-2010).]

Old chip was used. Car idle does go up idle then comes down as car warms up.Also map sensor is new.

Check to make sure the Service Engine Soon light comes on, key on, engine off. Then check for ECM trouble codes.

code 33 map sensor. have installed new one. drove it with no difference.

Code 33 is MAP pressure high. Is the vacuum line attached to the MAP sensor? Do you have full vacuum on that line at all times?

yes line is on map sensor. yes there is vacuum. engine has lack of power. put brake on and accelerate causes engine to backfire and stall out. will look at it more in the next few days. Thanks for your help.

DId you disturb the timing from when it ran good? Did you set the timing correctly if you did?