rotarybeat1287

iTrader: (16)

hey,
i was wondering if any of you have disabled the cold start assist mechanism for your FC's. mine works fine and dandy except for the fact that it will start and run without it just fine. it's just picky of when it wants to work. i am curious if any of you don't use it, disabled or have removed it. its a really annoying thing to deal with leaving for school in the morning and other places where i need to be quiet. im not a fan of fogging out the entire parking lot either. lol. any input on this will be great. thanks guys.
-allen

Turbonut

iTrader: (1)

There was a TSB (1990) instructing dealers to remove/disconnect the system as it proved to be useless.

spot_skater

Rip it out... then again, I'm pro- removing things unnecessary to make the engine run...

2713ddddavid

iTrader: (1)

I think he means the 3000rpm startup (he refers to not wanting to wake up the entire neighborhood).

If its the 3000rpm startup try putting your car in 1st gear and keep your foot on the clutch when you start. That will bypass the 3000rpm spike that you get for the first 20 seconds. Its still going to idle up some what if the thermowax is operating correctly

If you are speaking of the cold start assist, which is NOT the 3000rpm start up, then what turbonut posted is the info you are looking for.

rotarybeat1287

iTrader: (16)

i would but my car is an automatic. lol. but i thought that was the cold start assist thing. where it jumps to 3k rpms. thats what i dont want.

2713ddddavid

iTrader: (1)

Stand facing you car with the hood up. On the bottom of the radiator on the drivers side facing the engine you will find a sensor with two wires. I think its there on the automatic 7s. Try unplugging the wires and see if that stops the 3000rpm startup. (it should)

The "cold start assist" is a USELESS system that injects a small amount of a antifreeze/water solution into the intake if the outdoor temperature is below a certain point. The container for this solution is located on the passenger firewall in the engine bay. You should remove this container and securely cap off the port where it feeds the intake. If there is no container located on the passenger firewall then it has most likely already been removed per the above mentioned TSB.

The "cold start assist" and the "accelerated warm up" (3000RPM start up) are not the same thing, the latter is emission related, the former is just a stupid, useless idea.

rotarybeat1287

iTrader: (16)

thanks for clearing that up. ill look into doing that and see if it helps.
-allen

Aaron Cake

iTrader: (1)

We are talking about three different systems here...I don't understand how this is so confusing as it has been covered many times.

The sub-zero assist is the tank of coolant on the firewall. It's useless. Remove it.

The "cold start" (thermowax) is located on the throttle body. It holds the throttle open at 1500RPM while the car warms up and gradually drops the idle as the coolant increases in temperature. Some people remove this but I don't know why as it makes driving a cold car a royal pain in the ***.

The accelerated warmup system is the AWS solenoid that is responsible for the 3K startup. This was originally done to light off the cats quickly to control emissions. You can safely disable this system by either removing the AWS solenoid or simply jumpering the harness connection at the bottom drivers corner of the rad (thus bypassing the thermoswitch).

jgrts20

MY car just starts at 800rpms, I want my car to startup at 1500 as explained up above "Cold start" I dont care to much about the accelerated warmup(not working anyways). Ive just recently change my TB, what did I miss(maybe) causing the "cold start" not to work?

Chris

NZConvertible

It's confusing because people keep using the wring names to describe the systems, including you!

It's the sub-zero start assist system, and is the only thing that assists the engine to start other than the BAC valve.

The thermowax is not cold start, it's cold idle (or fast idle). It does nothing useful during starting.

jgrts20

So could I have a bad BAC valve or is it the water thermo valve causing my problems? refer to:https://www.rx7club.com/2nd-generation-specific-1986-1992-17/help-water-thermo-valve-supposed-sucking-air-654278/

Thanks NZ, when you said BAC valve it dawn on me that I never reconnected it after installing the throttle body. My problem has been solved, just went out and connected it and valla it works.

Thanks
Chris

jrosado5

SO what is wrong when the 3000 RMP thingy only works to about 1800-2000 RPM? It sounds like it wants to work, but mine does it low? Is it really necessary? Can it be removed? What are the consequenes? I kind a like it because it gets the juices flowing faster in the engine!

Can someone also please explain thermowax operation to me? What does it do? What goes wrong with it? Does it malfunction over time? Symptoms of malfunction? Replacement, ect.

Force Fed

It's a piston assy w/ wax under the piston. The wax expands w/ heat and pushes the piston up, disabling the fast idle at the proper temp. If it doesn't work (like mine I think) it just never comes off fast idle.