User: What is the part number for the cold weather drivability tsb replacement ecu
Assistant: The part number for the cold weather drivability TSB replacement ECU for the Toyota Celica ST165 is 89661-20361. This ’89 ECU was issued by Toyota in a Technical Service Bulletin around February 1989 to address cold driveability problems. It has gray connectors instead of the yellow ones found on the ’88 ECU and is considered an updated replacement part that works fine with the wiring and sensors of the earlier models. It is somewhat rare but is the official Toyota listed replacement ECU for both ’88 and ’89 years aimed at improving cold weather driveability.
So if you are looking for the specific TSB replacement ECU to improve cold drivability, you want the Toyota part number: 89661-20361.
This has been discussed by enthusiasts and confirmed as a TSB-related update ECU in the forums and parts discussions【4:7-12†alltrac-forum-posts_23.txt】.
User: What production date did the wiring harness update take place
Assistant: Based on the information from the forum discussions, the wiring harness update for the ST165 related to cold weather drivability and other improvements generally took place around late 1988 production. References to cars built up to approximately VIN number 2490, with some users noting harness and ECU differences in cars produced from late 1988 into 1989.
For example, users mentioned the newest ST165 with VINs around 0008883 being from December 1988, with differences in harness and connector colors between the ’88 and ’89 ECUs noted as well. This suggests the harness update happened in the production run near or shortly after December 1988, correlating with the ’89 model year update ECU part number 89661-20361 issued in a 2/89 TSB.
Therefore, the wiring harness update took place around the end of 1988 production, roughly December 1988, coinciding with the release of the updated ’89 ECU that addressed cold weather driveability issues【6:1-2†alltrac-forum-posts_08.txt】【7:7-15†alltrac-forum-posts_23.txt】.
If you want to identify if your specific car has the updated harness, you can check the production date sticker by the driver’s door latch and the connector colors on the ECU harness. The updated ’89 harness typically features gray connectors instead of the yellow ones found on earlier ’88 models.
User: How much horsepower does a sard ecu add to a 3rd gen 3sgte?
Assistant: The SARD ECU for a 3rd gen 3SGTE is generally a remapped or tuned ECU designed to work with higher flow injectors (like 550cc SARD injectors) and better fuel management. However, the actual horsepower gain from just swapping to a SARD ECU alone is not clearly quantified in exact numbers in the sources available.
From user reports and forum discussions, fitting a SARD ECU usually accompanies fuel system upgrades (larger injectors, fuel pump) and sometimes turbo upgrades. The ECU tuning and fuel mapping allows for safer increased boost and richer fueling, which can add noticeable horsepower beyond stock, but it is not a standalone fixed HP gain.
Users mention needing the correct injector type (SARD injectors) because the tuned ECU is mapped specifically for those, and running different injectors can cause starting/lean issues. Thus, the horsepower gain depends on the overall supporting modifications like injectors, fuel pump, turbo, and tuning.
Typical stock 3rd gen 3SGTE engines make around 210-240hp. With minor bolt-ons and proper tuning (including SARD ECU), power up to around 300hp is considered attainable, but that involves more than just the ECU upgrade.
So, in summary:
– The SARD ECU itself is a base for tuning and managing upgraded fuel systems.
– Horsepower gain depends on other supporting modifications.
– It enables running larger injectors and higher boost safely for power in the 280-300hp range.
– Pure ECU swap alone is unlikely to increase power significantly without accompanying hardware changes.
This is reflected in forum discussions where people report needing the matching SARD injectors and making other fuel system upgrades alongside the SARD ECU to realize power gains. There’s no specific fixed horsepower number attributed solely to the SARD ECU in the available data【12:7-13†alltrac-forum-posts_25.txt】【12:3-10†alltrac-forum-posts_25.txt】【6:1-15†st162-forum-posts-merged-04.txt】.
If you’re looking for a measurable power increase, the ECU upgrade is part of an overall package including injectors, fuel pump, and boost levels, not just a standalone HP boost.