1975-80 Cadillac EFI FIV Fast Idle Valve Choke Heater Replaces GM PN 1606776, GM PN 1617956, GM PN 1628898 and is also known as Bendix PN 1181290 and Bendix PN 1181835

Now includes 2 Amp Fused harness with molded TB Grommet molded from a 3D printed mold and PA12 professionally 3D printed connector.

Car slow to reduce engine idle after start? Do you find yourself shifting into gear at an elevated idle RPM? Your Cadillac has either no fast idle or never reduces RPM after initial start? This is the part you need to restore the proper function.

More of the originals have gone bad than people realize because they tend to degrade over time; many times as the white thermal paste leaks or the internal heating coils degrade. My original lost partial function and was taking 11.5minutes from a temperature which it should have taken around 2minutes. Not wanting to wait for the full 11.5 minutes I typically shifted into reverse and the car would clunk into gear when shifted at an elevated idle RPM. Now that the FIV has been replaced it’s difficult to explain how good normal feels.

The originals have two heating steps. Once the valve is closed the motion trips the switch, by way of the arm, on the external switch providing partial but constant heat. The original never controlled to the ideal heat even as a new part.

These are an improvement over the originals and allow your car to move from fast idle to normal idle in a reasonable amount of time as the Cadillac Engineers intended. The external switch and mechanical arm have been removed and instead an internal temperature sensor monitors the actuator temperature and adjusts the heating accordingly. Heating is only applied when the temperature probe signals the need.

1976 1977 1978 1979 1980 Cadillac EFI Fast Idle Valve “FIV” or sometimes referred to as a Choke Heater Assembly – Or in the GM parts catalog as “Heater” in the “Baffle-Heater-Switch-Valve” section. This is a new part but not a NOS part. It replaces Delco Remy GM PN 1606776, GM PN 1617956, GM PN 1628898 and is also known as Bendix PN 1181290 and Bendix PN 1181835; All w/ EFI (See note at the bottom of the description detailing all model years using this technology EFI).

This valve is installed in the vehicle throttle body and controls air bypass. When the vehicle is cold additional air bypass is allowed which results in an increase in idle RPM until the vehicle is warm enough to run at a slower idle (normally not completely warm but warm enough to run without additional bypass).

This offer is for one NEW (NOT NOS) replacement FIV. The function is the same as the OEM original GM/ Cadillac part but there are some notable visual differences, some control differences and as well as some significant durability improvements.

I tried to sift through the applications to the best of my knowledge. You should verify your application. In 1980 these were only used on the 5.7L (350 cubic inch with California emissions option CA only). If you have a 1976 to 1979 Cadillac and it has fuel injection this should be the correct Fast Idle Valve for your car. 

I own one of these cars myself. If the FIV goes bad you will have issues with idle RPM. The RPM should decrease in a reasonable amount of time which is normally around 1.5 to 5 minutes depending on temperature. The most common original failure resulted in a valve which would no longer close and thus the car would never come down from fast idle or would come down but over a very long time. Often people compensate for the reduced function by adjusting the main idle screw. In all cases the main idle screw should be adjusted after replacing the FIV. If you are tired of long waits with high idle this part will correct the issue and will restore the operation to a normal/reasonable fast idle operating time.

There are a few reasons why the original FIV’s fail and I have attempted to address all known failure modes. The original FIV had a mechanical arm on an external micro switch which allowed a two-step heating; one for closing the FIV and one for maintaining closed (lower heat). I have eliminated the arm and instead an internal sensor monitors and maintains to a precise target temperature which is the same value as the original target value.

A second failure mode of the originals is the thermal paste leaks out. I’ve seen NOS parts where the description mentions that this is “normal”. Ironically that is true but it is due to a design flaw and seeing white thermal paste means at least some of the thermal paste/wax is no longer where it needs to be. The wax seems to serve two functions: The first is it bridges the wax motor/ wax actuator to heat sink gap. The gap is small but for the heat sink to warm the wax actuator efficiently thermal paste was used. The second, less obvious, function seems to have been to ensure the heating unit was able to efficiently heat the heat sink which the wax actuator is mounted. I’ve test original FIV’s which have the proper internal two step resistance but take an extremely long time to achieve the desired wax actuator extension. In contrast the same wax actuator heated directly is able to achieve the intended extension which indicates the internal heating elements have lost the ability to transfer heat to the actuator. To address this failure mode my heating element is attached directly to the heat sink and second I’ve added an oring inside the sleeve which seals on the actuator body. The clearance is also very tight. The o-ring material was selected as the best available for exposure to both gasoline and ethanol containing gasoline. While there is no direct exposure obviously a TB will be exposed to fuel fumes.

I tried to design the most durable valve possible. It took about 2 years of design, testing and sourcing. Due to the low volume nature of the interest in these vehicles I am starting with a professionally 3D printed glass filled nylon housing. The reason the new valve is cream colored is the material selected was simply the best available, regardless of cost, and is only available in “natural” cream color. The parts are laser sintered technology. The heat sinks are machined from solid brass. The o-rings are fluorosilicone due to it’s superior nature when considering the potential for both gasoline and ethanol added gasoline. The internal wiring is copper strand PFA insulated. The terminals are tinned brass.

My original is shown for reference only in some of the photos (Not being sold as part of this offer). You will receive the new replacement “natural” or “cream” colored part.

-The new FIV is technically a "plug-and-play" direct replacement and can plug directly into the factory original harness. However, the new part is polarity specific. Because of that I am now selling the FIV with a replacement wiring harness section including a TB interface grommet and most importantly protected by a 2 Amp fuse.

The FIV DOES have a +/- terminal. In 1979 the Eldorado used a dark blue wire for positive and black as ground. The side closest to the ~45 degree chamfer on the cap is the POSITIVE and the terminal closest to the round body is the NEGATIVE. This replacement part must have the wiring assembled according to the designed polarity. Please verify polarity prior to installing the replacement. Current draw during heating is roughly 0.7 to 1.1 Amps. Once at temperature the new FIV will go into a monitoring mode with a minimal draw until additional heat is needed to maintain the operating temperature. Cadillac designed the FIV circuit as part of the fuel pump system which uses a 20 Amp fuse. If the polarity on the FIV is reversed it will fail the FIV which is why I strongly recommend installing the fused harness, and 2Amp fuse, which I now provide with the FIV.

This is a new replacement but it is not NOS

The following additional application details are based on the coolant temp sensor for the same application. It correctly lists all Cadillac series and years which the FIV should work:

Used on 76 K on cars before VIN 480001* (*before 480001 the coolant sensor had a different style electrical connector but I believe the FIV is the same)

 Used on 76 K on cars after VIN 480000 (See * above)

 Used on 76-77 C,E

 Used on 77 K W/EFI

 Used on 78-79 ALL series W/EFI

 Used on ALL 1980 series W/EFI (350-8)

The assemblies are built and designed in the USA but some of the parts were sourced in other countries due to availability and willingness to work on a relatively low volume application. You may see some indication that the terminals were assembled. This is because the unit is verified to be working properly after final assembly (power applied to the connection using an OEM connector).

Housings - Made in the USA

Brass heat sink - Made in the USA

Terminals - Made in the USA

Actuator - Foreign made

Eldorado Biarritz Seville Sedan DeVille Coupe Brougham 76 77 78 79 80 1976 and 1980