I have a 93 LS, and the engine is making a knocking sound. There's alot of smoke on start up and while driving. The smoke is a greyish color. I'm looking at replacing the engine. My question is does it matter what year I get the engine out of? I mean can I use an engine from 90-92 LS in my 93 LS? Any help would be greatly appreciated.

 

I know the 1990-1994 should be identical. 1995 they made a couple changes.

 

if u have a 93..get a 93 engine. the 94 has some stuff that was added on but it might work. 90-92 is totally different. 95+ fuggedabouit.

 

how many miles were on the engine before it started knocking?

 

I have never heard of one of these engines "going bad" like that, but I guess its possible. Nothing lasts forever.... however are you sure its not the fan bearing? Mine went out and it sounded like a rod knocking, but it wasnt... it was the fan. The smoke could be from a faulty valve on your PS pump. Grasping straws, but maybe some hope.

90-92 engines are totally different from the 93 engines? I never knew that. Whats so different about them?

 

http://www.lexls.com/info/lsgenerations.html

scroll down to half way...more than 50+ additions were added from 92 to 93. both engine and trim related.

 

is it just the smoke or is it the knock as well that's bothersome. you might be able to fix the smoke with the additives for a little while longer.

 

i've heard of these engines lasting over 500,000 miles. so i would check all possibilties before takin on the trouble, not to mention expense, of a swap

 

I know. Me too. Thats why I thought it was odd to hear it was knocking. I dont know the miles of the engine though... the OP has never mentioned.

 

How many miles on the car, and are you burning oil? Maybe coolant?

Rob

 

Sorry I'm just getting back to you. Thanks for responding. The car has 171,000. While driving the car home from work the car overheated, I couldn't see the temp gauge because the instrument panel has blacked out. When the car overheated there was this loud noise and a very thick cloud of thick grayish smoke came from the tailpipes. It was so much smoke that the cars behind me couldn't see 2 feet in front of them. Every since then the engine overheats and there's a knocking and the car runs really bad.

I noticed that you guys said that I couldn't swap the engine from a 95 or better. That sucks because a friend of mine gave me a 96 LS400 with 78,000 miles on it that runs and drives but it has a Certificate of Destruction.

Any other suggestions?

 

Where there is a will there is a way, an engine out of a 96' probably could be made to work. You would have to swap over EVERY sensor/electrical component from your 93' engine to your 96' engine since it won't just drop in and plug up. If I were to go this route I'd probably swap over the intake manifold and attached components from the 93' to the 96' engine as a start. I've never done this so take my advice with a grain of salt... In my expertise with cars, I would say that it could be done if the only thing you swap in from the 96' is the long block itself.

 

swapping single components prolly won't work, the WHOLE drivetrain, incl. Engine, Transmission, Harness, Body Harness, and ECU will need to be swapped, you'll also be going from OBDii to OBDII, which is a PITA wiring wise.

 

If he only used the long block out of the 96' I think it could work. He would need to use the electrical components from the 93' including the wire harness and ecu etc. This type of thing has been done numerous times with Hondas and Nissans. Not saying it won't be a PITA, but if he's got a free 96', a dead 93', and a whole bunch of time, I bet it could be done.

 

wonder if 93 cylinder heads fit on a 96 shortblock?

A 96 has a different cam but is not VVti, correct?