Q: Engine swap ls400 Lexus 1990 to 1993 1UZ-fe

asked by on March 23, 2018

Hello im swapping s 93 ls400 1UZ-fe into a 1990 ls400 could you give me any advice as far as the swap?

My car has 26000 miles.
My car has an automatic transmission.

The engines themselves, that is the blocks and cylinder heads, are identical in both model years. So, they are a direct catalog interchange, have identical castings and so forth. However, the computers for the two years do NOT interchange. That raises the distinct possibility that engine management controls, including any and all electronic components and sensors, from the 1993 model year engine will be a mismatch for your existing 1990 engine computer. You will either have to check the part number of each and every such carried over component (actually not hard to do using on-line Toyota catalogs) to confirm exact catalog interchange or simply just carry over all components from the 1990 engine to the 1993 engine. It is also possible that components other than the long block are not identical such as manifolds, the throttle body and so forth. Basically, the engines are interchangeable but you will simply have to pay close attention to the components and controls attached to the engine so as to avoid computer issues. If you need assistance with your engine replacement, YourMechanic professionals in certain locales can assist with that. Please simply inquire based on your locale. If you have further questions or concerns, do not hesitate to re-contact YourMechanic.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing


Experienced Mechanic?

Earn up to $70/hr

What others are asking

Car fans stopped working
The fans on your car work together together and get the power and control from the fan module on top of the radiator. If one fan is working but not the other then that fan motor would need to be...
My car shuts off while driving and light comes on and I can restart my car could it be alternator - 2006 Saturn Ion
Hello. You should have the battery fully charged (https://www.yourmechanic.com/article/how-to-recharge-a-car-battery) and then check the charging system (https://www.yourmechanic.com/article/how-to-test-your-alternator_2) to see if it is charging the battery. Replace the alternator (https://www.yourmechanic.com/services/alternator-replacement) if it is not charging. If you need help with this, a...
Truck is overheating - 1992 Chevrolet C1500
There are a few things to check over. The water pump produces flow. To check this remove one of the heater hoses (small diameter) going to the heater core. Locate the hose end to a container to check flow of...
My door will not latch closed. 2003 Ford Taurus
Hi there. It sounds like the latch assembly is freezing up. This commonly occurs in cold weather if the latch is old and if there is any debris built up in the latch. In some cases cleaning it out with...
Car overheating, rough idle, hard to start, coolant does not circulate.
Hi There, It sounds like you may have two separate issues going on here that may possibly be related via the coolant temperature sensor (https://www.yourmechanic.com/services/coolant-temperature-switch-sensor-replacement), which is what relays the temperature of the coolant back to the ECU which then...
Car doesn't turn over and the engine doesn't start.
Hi there. When changing out the body control module the Immobilizer system was tripped. Either the system will have to be reset or the Immobilizer system control has to be replaced. If you need further assistance with your engine not...
Breaks
If your brake pedal is going to the floor and you are not losing any brake fluid from a leak then the problem is inside the master cylinder and will need to be replaced and system bleeding of air after...
I have a new 2017 mercedes c300 and wanted to know about switching it over to LED headlights. Is this something that I have to sw
Hi Adam. Thanks for the question today. I believe Mercedes-Benz recommends swapping the headlamp housing when converting to LED bulbs on their C300. However, you might want to contact an MB dealership to get clarification from them, as I believe...
Spark plugs/Coil plugs wont spark and car will no longer start because of this.
The mention of the camshaft position code and the car's mileage make me think of a timing belt problem. If you can see the camshaft you might want to check and see if it is turning while the car...

Related articles

A Buyer's Guide to the 2012 Lexus GS450h
The The 2012 Lexus GS450h is for those who want to drive a hybrid, but would prefer to still enjoy a luxurious and safe ride. Fortunately, as this sedan proves, going the hybrid route doesn’t have to mean you lose...
The Best Used Cars to Buy If You Like to Go Off-Roading
Your Your best bet for off-roading is a 4x4 SUV. Depending on the model that pleases you most, though, you might have to shop around a bit to find a good used one. That’s simply because off-roaders typically become very...
The Best Used Cars to Buy If You’re a Photographer
If If you are a photographer, and you’re considering buying a used car, the big thing to consider is the type of photography you do. Thanks to the advances in digital photography, chances are you’re not hauling around a lot...