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turbo_180
08-23-2005, 03:24 PM
I have been running my car with an SR20 for about 3 months now. It has ran super rich with no power from about the second week into it. Also when i would get into boost i would loose power.

Well last weekend i was at a friends house trying to figure out the problem and he said his ran that way when he put it in. So he unpluged the TPS and it cleared up getting around 26 to 28 miles to the gallon.

So we unpluged mine and it cleared up and im getting 26 miles to the gallon. my question is Should i replace the TPS with a working one or leave it un hooked? If i replace it what is the USDM Equal?

FITZ
08-23-2005, 03:25 PM
What's a TPS?

initial what?
08-23-2005, 03:28 PM
throttle posistion sensor.
and thats all i can answer

ameenIT
08-23-2005, 03:32 PM
IF IT TAINT BROKE DONT FIX IT...

turbo_180
08-23-2005, 03:42 PM
So pretty much as long as its running this way dont change it? I personaly think that i can continue to run with out one my friend has for about a year now and he runs 12psi with no problem. But neither one of us know for sure if it should be replaced.

silverline
08-23-2005, 05:11 PM
you should first test it.. ot closed then watch it rise up to wot.. document voltages make sure they are steady.. should start from .3v - .5 and got up to 4.5-5v

King 240
08-23-2005, 06:23 PM
could be that its gone out, I'd replace it with a new one.
Mine was in incorrectly causing my car to go to shit, once I replaced it bad, running good.
Also check your intercooler piping, fuel injectors, and cracked hoses around the engine. These can lead to the car running like crap as well.

When was the last time you changed your filters (fuel intake and inline).

turbo_180
08-24-2005, 09:10 AM
Everything was just changed the car is running great without it pluged in the fuel pump is about 3 weeks old and i did the fuel filter at the same time. The intercooler was just put on after the TPS was unhooked So i dont think that had anything to do with it...

When i go to buy the replacement what US car used the same one that always makes it easier to buy a new one.

Voodoo
08-24-2005, 10:20 AM
From the voltages Rodney posted...

I'll bet it is the same TPS that the KA24DE uses.. that voltages are the same.

As for running with it unplugged, you can do what ever you want, but the TPS was put on there for a reason; it tells the ECU how much the throttle is open.

turbo_180
08-24-2005, 01:02 PM
word you guys are alot more help than club240 and nico i posted this tread there like on friday and no one has any idea what to tell me and they also tell me that my car will not run with out the TPS but its been running for about a week now so i guess they are wrong. im gong to see if the KA TPS will work if not im going to try a 91 SER one because all the other parts are the same.

silverline
08-24-2005, 01:17 PM
it will run but loose throttle response.. and maybe rich. Also may need to adjust it when you install there is a little play in it so you can do that.. you need to or it will run awfull

Voodoo
08-24-2005, 06:48 PM
Look At the Factory Service Manual... It will tell you how to adjust it.

_al
08-25-2005, 10:07 AM
You need the TPS and you need to reset it per FSM instructions.

http://www.camel-towing.com/docs/-%20FSMs%20-/240SX%201995/EC.pdf
(EC-145 for you S14 95 owners)

1) the voltage when accelerator pedal is fully released is approx 0.3-0.7v
2) the voltage rise is linear in response to accelerator pedal depression
3) the voltage when accelerator pedal is fully depressed is approximately 4v

An S-AFC or PowerFC with Commander is extremely useful when troubleshooting the TPS.

Someone49
08-25-2005, 12:12 PM
al owns...

thats all

datboibrad
08-25-2005, 01:35 PM
From the voltages Rodney posted...

I'll bet it is the same TPS that the KA24DE uses.. that voltages are the same.

As for running with it unplugged, you can do what ever you want, but the TPS was put on there for a reason; it tells the ECU how much the throttle is open.

ka and sr tps are totally different. the rod in it that it uses to read the position of the throttle body is different. not to mention the plugs arnt the same by far

also any car will run without a tps. your motor ecu runs your car off three major readings. MAF/MAP sensor, TPS, and CAS (crank or cam angle sensor)

if one isnt reading 2 out of 3 times the ecu can still run the car just not as efficiently. I no on my integra one of those 3 where always fucked up and i had no problem just didnt run as perfect as it could

_al
08-25-2005, 02:29 PM
ka and sr tps are totally different. the rod in it that it uses to read the position of the throttle body is different. not to mention the plugs arnt the same by far

Incorrect. My SR is using a TPS from a KA ... an automatic KA because it has an output for WOT. You just need to swap out the plugs.

also any car will run without a tps. your motor ecu runs your car off three major readings. MAF/MAP sensor, TPS, and CAS (crank or cam angle sensor)

The ECU uses TPS signal against engine RPM to determine load. An engine will run without it, as it is the prescribed method for adjusting idle and timing, but it's not designed for operation w/o it. Some primitive standalones don't have TPS, and some use TPS as it's only method for metering air. KAs and SRs using the factory ECU function properly with TPS.

datboibrad
08-25-2005, 06:21 PM
Incorrect. My SR is using a TPS from a KA ... an automatic KA because it has an output for WOT. You just need to swap out the plugs.



The ECU uses TPS signal against engine RPM to determine load. An engine will run without it, as it is the prescribed method for adjusting idle and timing, but it's not designed for operation w/o it. Some primitive standalones don't have TPS, and some use TPS as it's only method for metering air. KAs and SRs using the factory ECU function properly with TPS.
well i tried using a dohc ka tps on my sr and it wouldnt work. they where completely different in design. not to mention the KA hadsome other plug on it. then i decided to use the ka throttle body and it made things worse

_al
08-26-2005, 10:09 AM
well i tried using a dohc ka tps on my sr and it wouldnt work. they where completely different in design. not to mention the KA hadsome other plug on it. then i decided to use the ka throttle body and it made things worse

I don't know why it wouldn't work, man. Mine worked without a problem, again all I did was match harness plugs.

91-95 KA TPS is a direct plug in.

If a KA TPS can't be found for some strange reason ...

I called JWT and asked to speak with their engineer. Her was kind enough to look up in his US and Japanese manuals for parts crossovers for TPS sensors. He told me to get a TPS from a 90-93 Sentra SE-R or 200SX SE-R 5-Speed since they share the same Nissan part numbers. So I went to the Junk Yard and picked one up, it bolted on and plugged in and worked great.

Voodoo
08-26-2005, 10:23 AM
ka and sr tps are totally different. the rod in it that it uses to read the position of the throttle body is different. not to mention the plugs arnt the same by far

also any car will run without a tps. your motor ecu runs your car off three major readings. MAF/MAP sensor, TPS, and CAS (crank or cam angle sensor)

if one isnt reading 2 out of 3 times the ecu can still run the car just not as efficiently. I no on my integra one of those 3 where always fucked up and i had no problem just didnt run as perfect as it could

Hmmmm...

Looks like someone needs to do a little research....

What a novel thought...

datboibrad
08-26-2005, 10:38 AM
Hmmmm...

Looks like someone needs to do a little research....

What a novel thought...
sorry i dont sit and read books all day. i go by what ive tried and either did or didnt work. i know hondas like the back of my hand, although Nissan is still new to me, so im having to go by trial and error on most things since the amount of common knowledge on them is very limited to a few people on here :rolleyes

datboibrad
08-26-2005, 10:49 AM
I don't know why it wouldn't work, man. Mine worked without a problem, again all I did was match harness plugs.

well reason i said it wouldnt work is because the TPS from the KA has two plugs on it and the SR one has one. so how does that work out?

also id have to use it with the KA tb cause it wont fit the SR tb because of the throttle rod is completely different. but the KA water lines on the bottom of the tb hit the thermostat housing thing for the lower radiator pipe. they basically go the opposite waysof the sr water lines. can those be twisted with some pliers to turn the other way without causing a leak?

Voodoo
08-26-2005, 11:05 AM
well reason i said it wouldnt work is because the TPS from the KA has two plugs on it and the SR one has one. so how does that work out?

also id have to use it with the KA tb cause it wont fit the SR tb because of the throttle rod is completely different. but the KA water lines on the bottom of the tb hit the thermostat housing thing for the lower radiator pipe. they basically go the opposite waysof the sr water lines. can those be twisted with some pliers to turn the other way without causing a leak?


Only the Auto TPS on the KA has 2 plugs. and you leave the other one unhooked. The Manual TPS has 1 connector.

The second plug on the Auto KA is for the transmission kick-down
I run a Auto TPS on my 5-speed and leave the other one un-connected... no problems in 5+ years.

datboibrad
08-26-2005, 11:09 AM
Only the Auto TPS on the KA has 2 plugs. and you leave the other one unhooked. The Manual TPS has 1 connector.

The second plug on the Auto KA is for the transmission kick-down
I run a Auto TPS on my 5-speed and leave the other one un-connected... no problems in 5+ years.
well wait a minute my KA tps has two plugs but it came off a 5 speed. hmmm would it being a SOHC matter? if so thats probly the problem

Voodoo
08-26-2005, 11:11 AM
well wait a minute my KA tps has two plugs but it came off a 5 speed. hmmm would it being a SOHC matter? if so thats probly the problem

probably

datboibrad
08-26-2005, 11:18 AM
shit so at this point i either need another SR tb which i would rather or find a dohc sensor :(

_al
08-26-2005, 11:26 AM
well wait a minute my KA tps has two plugs but it came off a 5 speed. hmmm would it being a SOHC matter? if so thats probly the problem

Bingo.

91-95 KA TPS is a direct plug in.

I'm using the TPS from my 95 KA, but it's from an automatic. I believe I used the VG plug because it was prettier and I have an extra output for WOT built into he TPS for nitrous oxide.

turbo_180
08-29-2005, 03:13 PM
Okay i just did put the new TPS on this past week end the KA did not work at all it caused me to run worse ofs i used a SR20DE TPS from a B13 SER (sentra for those that dont know) it works fine just had to do a little soddering and re pinning but i had a friend help with that. so its running awsome now thursday i ran a 13.8 at 104 mph and a 1.7 60 footer at 12PSI.