Problem with Defi Bf Thermostat Connector Into a FC Water Pump thermostat hole."Help"
 

The "threads" appear to be different from both ends of the water pump connectore does anybody have any references into finding another place to connector the "DEFI thermostat switch" or swaping the wire into the OEM thermostat connector..

the defi sensor thread is 1/8PT and another adapter is 1/8NPT, what does that mean...? what is PT and NPT and what does a conversion adapter look like...?

might need to find an adapter that fits the defi thermostat but screws into the stock hole... i know for some (cant remember if im right or not) but some autometer gauges come with thread adapters to allow stuff like the oil pressure sensor to fit into the stock hold... check your local hardware store

PT and NPT are in reference to the thread pitch...or something. AFAIK those are imperial threads. Check for adapters at plumbing shops...most hardware stores probably won't carry stuff like that.

Now this may be an assanine question...but why are you replacing that sensor with the Defi BF one? Im pretty sure that water temp sensor goes to the ECU. Keep in mind I dont know what a BF thermostat connector does :)

plumbing shops... any links to plumbing shops

what is the thread size for the OEM tempature sensor..? 'Autometer' see's to have an adapter but i can't find the link for what i need to buy...??? anybody know the Defi is 1/8pt and the OEM is...?

ok i think i got it.. i Looked up "AUTOMETER.COM at the FAQ and it tells me for all "Rotary applications for Water Tempature switch is "1/8" NPT to M16x1.5" for the Adapter. Is this correct..

http://hp.autometer.com/products/acc..._adapters.html

this is the "Metric Adapter chart"

http://hp.autometer.com/techtips/faq..._adapters.html

i believe thats what your looking for right there

I think you removed your waterthermosensor. If I'm right you should put that back in immediately. It sends or receives (I forget) signals to or from the ECU and your car will feel like limp mode if you do not have it installed.

Yeah, I was about to say that.

Good call.

Just drill another hole in your waterpump housing and put your sensor there.

If you don't want to buy a Tap/Die kit. Take your WP housing to a maching shop. They should be able to drill the hole and tap for you for a resoanable charge.

James

If you have a 1/8" NPT adapter for your DEFI sensor just take out the stock sensor out of the location on the block next to the oil pressure sender under the oil filter pedestal and put it there. The stock sensor hole is threaded for 1/8" NPT and will fit right in with your adaptor. Only thing you may have a problem with is fitting it in there since space is cramped. Might depend on how long your sensor and adapter are.

^^ I agree...


And get that sensor back in. Without it, your gas mileage will go to shit, and your car will run like shit. That sensor sends a signal to the ECU. It tell the ECU how hot the motor is so that the ECU can regulate the A/F mixture based on the temp. At least that's what I was told....

yes, coolant temp sensor is the most critical engine sensor along with air mass

dont replace it with a gauge sender

dman
 

So if i connect either 10: water themosensor connector or 11: water thermoswitch connector (A/T, Trubo) im gonna have problems with the ECU no matter what... im just trying to find the Least problems to Instal this DEFI thermoswitch... If i have to Drill where should i drill at..? it suck that these two thermoswtichs need to be feed through the ECU... :(

Well if you wanna do it properly you're gonna have to go through a bit of crap for this. The best way as mentioned before is to drill and tap another hole in the waterpump housing. Probably close to the location of the thermosensor you pulled out there...
They sell 1/8" NPT taps anywhere...and the recommended drill bit for that is 11/32.

so those thermoswitchs need to be connected anyways

hey.. what about splicing the OEM thermoswitch sensor cable TO the DEFI cable switch.. would that work instad of removing the pump and drilling a hole...?

Naw each sensor is calibrated for a different purpose. Trust me i tried something similar to this ;)

Just wondering why you dont try what I recommended? I mean the stock gauge isnt all that accurate anyways and if you have an aftermarket one you dont really need it. Although the s4 temp gauge is superior to s5 when you have an aftermarket gauge you dont really need the stock one in my opinion. No drilling required, about as easy as it gets. Plus I feel the stock location is the best since that is probably the hottest point in the coolant system.

you know whats weird.. my thermosensor was broken off for like.. atleast a year, once i replaced it, i saw NO changes in my car's gas mileage, idle, temp, anything..

Are you serious...? then i should have no problem getting an adapter and leaving one of the thermosensors plugs dissconected from the ECU...

i wouldn't..

its there for a reason, and does do something for sure... im just saying :)

you could try if you wanted.. but i wouldn't recomend it.

There is always a chance....that your car was having bad gas mileage before this happened to ;) So, there was no change.

What year is you FC? Turbo or non? Current gas mileage?

James

i have never calculated my milleage..

but, at $101.9 (current cost/Liter of gas)driving to work 6/7 days a week, through heavy traffic, about 30 minutes each way, i pay max 45$ a week.


its a NA, 1986, GXL model, with 137,000 KM on engine.