Rotary_Junkie

K 86 gxl, my original radiator did not have a sensor on top by the cap. i put in a different one from my other gxl and it has a sensor but its broke and no wire connector. so i got a new sensor but where does it go into the wiring harness? and will this make my dummy add coolant light go off? my car has had that light on for 3 years now lol i daily drive. i just added antifreeze for the winter and burpped it so no air pockets and i have the proper amount of coolant. my car floods all the damn time and somtimes im lucky and it doesnt. fixing this add coolant deal, will it solve my flooding problem? seeing as the ecu doesnt know the coolant temp and my car stays in warm up mode and it tends to flood when i park it. i have new injectors but with this cold *** missouri weather im having a hard time starting it. appreciate all the help. Or do i have the wrong sensor in mind? do i want to replace the coolant temp sensor underneath the radiator?


when you think you know all anout rotarys then comes up somthing new lol

RotaryRocket88

iTrader: (7)

The sensor on the top of the radiator is the coolant level sensor. Yes, you need to get one with a non-broken connector, and find the wire from the harness. It normally routes along the passenger-side of the radiator, and comes from the harness somewhere in front of the radiator. The low coolant light needs this sensor.

Hot start/Flooding issues are related to the water temperature sender, which is on the back side of the water pump housing. This is not the level sensor or the temperature switch on the bottom of the radiator. Separate things.

Check this thread for an explanation of how the ECU uses the temp sensor to determine fuel injection on start up: https://www.rx7club.com/2nd-generation-specific-1986-1992-17/looking-car-has-hot-start-problems-499744/

Rotary_Junkie

thanks man. i looked at the other wiring harness that had the sensor and i found the wire and ofcourse my was cut off. and i also changed the coolant temp sensor on the water pump. wont notice if it works till tommorrow. if im still flooding i think im going to buy rebuilt injectors.

i just dont understand why my stock radiator did not have a spot for that sensor. huh? beats me.

also on my other fc on the neck connected to the water pump has a sensor screwed into it. mine that drive does not. weird same cars same years. 86 gxls

RotaryRocket88

iTrader: (7)

Automatic NAs and TIIs have a thermo-switch on the thermostat cover (the neck you mentioned) that is used to switch on the small electric fan.

Rotary_Junkie

got ya on the fan. thanks. change the coolant temp sensor and it still floods. im thinking fuel pressure regulator. lets say my pressure is supost to be 60psi. can it go bad and the pressure go up to 80. i ruled out the stupid short drive crap cuz i learned the 4 yrs ago. also new injectors and coolant temp sens and new ignition coils. so regulator or maybe stronger spark. msd blasters sound tempting. lol dont think its possible but can a rotary actually be out of timeing? the performs amazingly just get it started most of time cuz of it flooding. plz dont redirect me to the unflooding procedure!! i know i have switches in line with the fuses so i dont have to pop the hood.

RotaryRocket88

iTrader: (7)

I don't think you should throw parts at it. If something fails a test, replace it, but there's no reason to blow a bunch of cash on things like MSD boxes. The stock coils are actually very good. FPR? Unlikely, but you can test fuel pressure with a gauge tee'd into the feed line. Specs are in the FSM. Timing? Possible if someone played with the CAS. Check with a timing light.

Double check that thread I linked to. The problem isn't necessarily a bad thermo-sensor; the problem is the ECU's starting fuel map is WAY too rich under warm conditions. That's not a problem you can fix unless you have a programmable ECU (Rtek 2.x, standalone). The best you can do is rig up a fuel cut switch, or a switch for the thermo-sensor to alter starting fuel.

Rotary_Junkie

well i have a fuel cut off switch doesnt keep it from flooding. cas? crank angle sensor? you mean lobe angle sensor cuz there is no crank maybe. im going to play with it. that cld be it becuz i had the issues with my 240 all i had to do was advance the timing. also my cas/las is stripped out so no nut or bolt keeping from moving.

have a code being thrown now. according to it, its either o2 sensor or intake air temperature sensor=which i have no clue where it is.

Rotary_Junkie

please help!!!! bump!!!!! i found out two spark plug wires were bad and changed them. checked the timing. changed thermostat cuz it was stuck closed. and no air in coolant lines. i drove and ran the car 7 times tonight. packed everything up and was ready to leave it didnt start and aparantly flooded. so wtf?! didnt do this last year. shop was 70 degrees and very warm today for missouri. im getting ticked off, my buddys are having fun in the snow and my damn car isnt reeliable for ****! Battery?? Stronger spark?? i got new plugs. higher octane than 87 or 89? is that my problem? air temperature sensor? where is that? injectors have been changed and pressure regulator. but didnt change the injectors underneath-secondary injectors? please help!!!! ive read all this bullshit but nothing has helped.

Rotary_Junkie

also with the link ....doesnt help cuz it doesnt matter if the car is hot or cold it floods/doesnt start so it floods ofcourse

RotaryRocket88

iTrader: (7)

What's this about the bolt holding the CAS being stripped? If the CAS is moving around, it's causing serious changes in timing, which could definitely make starting hard or impossible. Not to mention have a huge effect on performance / potentially blow the engine.

CAS = crank angle sensor, even though there's technically no crankshaft (it's an eccentric shaft).

It's less common, but dirty fuel injectors can drip fuel into the intake, which will flood it under any conditions. Servicing is pretty inexpensive, but you'll have to use an extra set or have the car down for days: http://www.witchhunter.com/.

The injectors under the intake manifold are the primaries, which are used for starting. The injectors on the outside of the intake manifold are the secondaries, which are not used for starting, but they can also leak.

Rotary_Junkie

thanks man. no luck though. my conclusion is i have a loss in compression. i have another motor that i have to put back together and thats my plan. just curious on what my compression read on my 13b and just hook up the tester to the trailing spark plug hole?

RotaryEvolution

iTrader: (30)

use the leading hole(bottom spark plug). remove both leading spark plugs, charge the battery fully, remove the schrader valve from the line leading to the compression tester and get a reading of each peak bounce while cranking the engine over with the throttle wide open. remove the EGI fuse while doing the test.

if at or below 85psi then you found your issue.

Rotary_Junkie

thank you. will be trying that. also i got a great idea. vaccum leak? i dont have the carbon filter black can anymore. ripped that out. can someone give me link on what vaccum lines shld be capped and ones not. also those lil sylanoids with filters, going to make sure they are not clogged.