Chevrolet Repair: Spudder on cold start and going up hill slowly, correct temp, sensor readings

Question
I own a 1988 Cheverolet Silverado and I just had a new engine installed by a mechanic. It is hard to start when it is cold and spudders quite a bit. When going up hills slowly it will spudder and act like a vehicle does when it is vapor locking. I would appreciate any answers on this. I have taken the truck back to the mechanic that installed the motor and he ran a fuel system check and said he couldn't find anything wrong. Thanks

Answer
one more thing to check....make sure that the o2 sensor readings are good. You could also just disconnect the o2 sensor and see if that makes a difference. if that helps you need a new one.

Mark





Hi Donald, this is a hard one to answer without driving it. I would first check to make sure that the coolant sensor is reading the correct temp. I have seen these sensors send a reading to the computer when it is cold telling the computer that it is like 180 deg. This will make the engine start hard and run poorly because it is running lean. Also fuel pressure needs to be around 10 to 13 psi. If you haven't put on a new fuel filter do it now. Be sure the engine timing is set correctly because that will really mess things up too!

Sorry I can't give a better answer

Have a Nice Day                Mark