SES light on and power loss

[ba96ta]

My brother has a 93 Caprice with the L05 engine and about 145,000 miles. recently his car has been lossing power when he starts getting on it and the SES light comes on. When he starts it its fine then starts acting up after he has been driving it. The engine doesn't miss just feels rally underpowered like it was towing something heavy, especially at higher rpm. He recently changed his fuel filter so its not that. I am thinking its the fuel pump. Any replies or suggestions would be greatly appreciated Thanks

Joe

[maximus]

Does he drive the car hard? 145,000 is somewhat high mileage. the engine may be worn, but i dont know

[LM13]

Originally posted by ba96ta
My brother has a 93 Caprice with the L05 engine and about 145,000 miles. recently his car has been lossing power when he starts getting on it and the SES light comes on. When he starts it its fine then starts acting up after he has been driving it. The engine doesn't miss just feels rally underpowered like it was towing something heavy, especially at higher rpm. He recently changed his fuel filter so its not that. I am thinking its the fuel pump. Any replies or suggestions would be greatly appreciated Thanks

Joe

maybe he needs a tune up?
one of the spark plug wires might be shot

[ba96ta]

The problem comes and goes his car runs smooth when this happens just has no power. I'll tell him to check his plugs and wires and possibly his coil. thanks for the reply

[DR2000]

Yeah, I'd start from the wires too. Once one of my wires burned through (old age) and sometimes it would work, sometimes it wouldn't. But usually when I really got on it the signal would get through, and was acting up under no load.

[stompah]

145,000 miles so many things could be the problem. First of course as mentioned a basic tune up. Then elimination starts.


1. Is it the engine itself. A compression check is required and could be done when swapping plugs. I doubt it could be a bad cam or lifter but hey its possible.

2. Ignition. Is the distributor working properly and giveing the proper amount of advance? Most everything else should be covered by the tuneup.

3. Fuel delivery. Anything from a weak pump to an injector being dirty or worn.

4. Could be the computer and sensors. Are they all present and working?


It doesnt have to be checked in that order. Thats not the only possibilities but just a starting point. Its possible that the car is running on 6 or 7 cylinders.

[capriceman]

Is the engine hard to start when it's hot?
Could be a leaky head gasket.
To check if the lite is faulty, try the do it yourself diagnostic test.
Find the ALDL, computer connection under the center dash, take a short wire, put one end into the diagnostic test terminal, the other into the ground terminal, turn the key to the run position.
DON"T START IT. The computer doesn't like that.
If the SES flashes a 12, the diagnostic system is working.
It'll flash once, pause, flash twice. It'll repete 3 times.
If it flashes other codes, then the computer recorded a problem and is trying to tell You about it.
Or You could get a scanner at the parts store for like $30.00

[ba96ta]

It was the O2 senser. Thanks for the replies