Hi.. i have a 94 z28 6 sp with LT1 350 engine. My engine was rebuilt in July along with new rad etc. Has been running great until last week, where one of the lifters had a problem. Brought it to my mech,
they contacted the company who did the rebuilt, sent it back to them, they did something??? (took 2 days) got my car back and now when i accelerate in 1st gear it chugs badly (especially up a hill - looks like i dont know how to drive!),, as well as when i shift to 2nd. It does it when I am decelerating as well to the point in 1st, that it sounds like it is going to stall. I brought it back to the mech and they test drove with me, said that because
the computer was disconnected it had to learn the way i drive and adjust and if it still happens after a few days to bring it back. The engine aslo seems to chug rattle when I accerlate in 3rd or 4th, while giving it a lot of gas,,,The enging does not sound at all the same as when i brought it in for the lifters. I asked if the rebuilt company would have completly changed my engine to a different one. they said no, that it was not enough time to do it.

any advice on the chugging and what my mech said to my computer learning the way I drive!

I love my car!

 

that doesnt make sense...a computer doesnt learn how you drive, and if it was disconnected i dont see how you could of started it up or driven it, and if it was a bad lifter you wouldnt need to send the entire engine back

 

Is the check engine light lit?

 

dont hold me to it and im far from a mechanicbut it kind of sounds like fuel problem although i dont see how thats possible considering they didnt mess with that. It also sounds like ur getting fluid in the engine. My personal opinion and advice is to take it to a local Chevy Garage and get them to run a diagnosis test and check for compression for leaks and blown seals. Im hoping this might be a little helpful....

 

Hi.. thanks for your responses.....when i brought the car to the mech shop (they pulled out my engine, sentit to be rebuilt and reinstalled it back in july), they told me the company who rebuilt my engine requested to see the engine, so they drove it to them to fix the sticking lifter. So they did what they needed, disconnectng the computer, the batterie, taking apart he engine to fix,, put it back together hooked the computer and battery and sent it back to mech and then to me. My friend said maybe they missed connectng a hose and sounds like a vacumm thing. ...... and he said that the computer needs to relearn,,from being rebooted, but not they way I drive....

 

Hi.. thanks for your responses.....when i brought the car to the mech shop (they pulled out my engine, sentit to be rebuilt and reinstalled it back in july), they told me the company who rebuilt my engine requested to see the engine, so they drove it to them to fix the sticking lifter. So they did what they needed, disconnectng the computer, the batterie, taking apart he engine to fix,, put it back together hooked the computer and battery and sent it back to mech and then to me. My friend said maybe they missed connectng a hose and sounds like a vacumm thing. ...... and he said that the computer needs to relearn,,from being rebooted, but not they way I drive....

 

I had a near exact same situation after I had my engine in my 87 rebuilt. About 6 months later it made the sounds you're talking about..a chugging...missing...sound. Changed the distributor and it worked again for a while, then started back up again...it was a bad ECM causing electrical probs with the distributor. It was a gremlin for a while with several mechanics before they got it right.

Just coincidence that it started shortly after the rebuild.

Hope this helps

 

HI.. thanks for your reply,,,, did you experience this as well? i also notice that when I am accelerating in 3rdat approx 2/5 rpms, 50 - 60 k the engine sounds like a washboard...the car does accelerate, (doesnt seem or sound as if it has the power it used to), but when i shift to 4th and drive at a steady speed, the washboard sound goes away. A friend looked at it and said the valvesshifters sound to loud and they think there may be a crack in a hose as well, another suggestions based on the sounds of the engine is the timing may be out..... AND its -7 and the car wont start at all this morning!