J-Rat

iTrader: (2)

Believe it or not, I have had better luck with the lamp Method... My .02

Tofuball

Allright, on the S5, am I testing the bottom (narrow) to be 1K-5K? What do I do with the top TPS? And what wires should I grab the resistance off of for the top one, and what is it's range?

My bottom one goes happily from 1K-2K and then when the hammer leaves it, it goes infinite.

Tofuball

Ah, comon now

(Bump)

RETed

There is nothing you can do with the full-range side.
If you want to check it, it should read ANYWHERE from 0 to 5k-ohms.
There is not set ranges where it's supposed to be.

How is your meter set?
The narrow range should read from 1k-ohm to a maximum of 6k-ohms.
If you got the "range" of the DMM set wrong, it'll look like it went to infinity.


-Ted

AJatx

iTrader: (1)

Ted, sometimes people refuse to listen.

Think about the TPS, it's like a POT where the mechanical arm or coil position will determine the impedance which in turn changes the output voltage to the ECU.

If the impedance is NOT within factory specs, then don't use the TPS.

Besides, I rather test the component the best possible before taking a swag and risking engine damage on a road test. You take the road test after you've personally verified all components are within spec and the wiring for each component has proper continuity and impedance.

If you can't operate a multimeter and understand it, please take it to a mechanic.

J

BOFHMike

Damn it, spent good time adjusting my TPS, and just relalized, I should have checked the fast idle cam first. Even through I tested my tps with the engine warm, some of the idle problems I'm having may be due to a maladjusted FIC. Oh shucks, back to the garage....

jjwalker

Just if it helps anyone, the relief solenoid needs to be ON at idle, at full operating temperature. The 2 LED method will tell you this and the resistance method will not.

BOFHMike

I have not adjusted the FIC or BAC yet, but I have replaced my TPS. With the TPS adjusted to 1k ohms the car runs well. (no hesitations, very even accelerations) BUT on the flip side, decellerations are bad. Low idle is gone completely. When she warms up it will not stay at 800, just drops down to 0 unless I put a slight amount of presure on the gas. I think it may be the BAC, Hopeing it's not the ECU.

I was having a lot of problems adjusting the TPS though. Warmed up the engine for 20 min and I would set the TPS to between 950 - 1k, started the car again, let it idle for about 5 min, then checking the adjustment. It would keep dropping to 500 - 750. Adjust it again to around 950-1k, and back to 500-750 after another 5 min idle. Went through about 6 cycles of this before it finally quit.

If air is in the water line to the thermalmax would it delay the cam movement to where it would take more then 20 min of engine warming before the cam was in the right position???? If so, how would I go about bleeding the line?

BOFHMike

Just a note... the FSM's sugest using the Lamp method followed by the resitance method to fine tune. (4a - pp 34 )

HAILERS

Ah bull. The manual sets the TPS using a couple of LED lights and has a provision for checking the TPS by observing the resistance of the pot.

The word APPOX is used in both paragraphs and if one reads the CONTROL UNIT section you can see the INPUT to the ECU from the TPS should be APPROX 1vdc. Just backprove the output wire of the TPS connector with it fully connected together and, with a hot engine, make sure the output reads APPROX 1vdc.

BOFHMike

After reading a BUNCH of posts relating to bad idle conditions from you and Script7, I can respect your input. I will have to check that section out more closely.

Easy_E1

iTrader: (3)

I need to do this. My car idles like crap. I do have the FSM. And I have seen it done when I was in SoCal a few weeks ago.
'87 TII. Any other pointers on this model would be appreciated.
I'm a noob when it comes to this car.

BOFHMike

Start by reading https://www.rx7club.com/2nd-generation-specific-1986-1992-17/video-still-crappy-idle-no-response-idle-adjustment-657023/ If you still need to adjust your TPS, come back to this thread. You may save yourself a LOT* of hassle. The guys go through a lot of trouble shooting an provide great diagnotic tips. It's 11 pages of worth while reading and will give you insight on systematic troubleshooting.

Easy_E1

iTrader: (3)

Thanks.

BOFHMike

Good reason to use more then one method of TPS adjustment while working on a 20+ year old car. I recently replaced my tps and only used the resistance method to set it, but still no low idle. Tonight I tryed the lamp method. I started with both lamps on and I adjusted until only one lamp lit. I was about to unplug the TPS to backprobe it and check the voltage and then resistance, but as soon as I grabed the plug, both lights turned back on. HUH?????? let go of the plug and one lamp went off again. Moved the plug back and forth a few times and the lamp would turn on and off. Yep, broken wire to the TPS (I can actually see copper). Since it was on the engine harness side of the connector I would have never caught it using only the resistance method. Now I hope I have enough wire slack to install new spades and connector.

BOFHMike

Follow up to my last post. After repairing the broken wires related to the TPS, I used all three methods to adjust my Tit. First resistance, then lamp, then voltage. Voltage and lamp were close to each other, resistance is several* turns off. Not sure what to make if it. I'm going to see what my idel does tomorow after I'm done with several other electrical clean ups.

I'm about to search the forums, but I'll ask here - Has anyone found a way on a NA to adjust the idel screw that works against the Thermomax? I can see the screw, just not sure how to reach it with a driver.
-=mike=-

HAILERS

Remove the throttle body and follow the instructions in the FSM.

BOFHMike

Yeah, I was trying to avoid any more dis-assembly. Every time I pull something off I find one more bandaid from the prior owner. Just noticed the steering column bezel was held in place with wood screws....

I'm determined to get this 7 running and back to a daily driver, so if it means one more dis-assembly, then so be it......
Thanks!

Seoul Seven

sorry to bump an old thread, but i had a question,

i just tried aaron cakes method and now my idle bounces 1100 to 1500.? My Car is NA S4

i feel like i did something wrong. Cause for my meter to read 1.000 ohms the screw was almost all the way tightned. When looking at the TPS plug with the hump face up, there are 3 prongs. One ontop and two lower. I adjusted so that the top and right one read 1.027 ohms. Couldnt get spot on but close enough i figured. If i tested the top and left one it read around 3.450 ohms. can someone clear this up? i cannot get my tps and idle set...

satch

iTrader: (1)

The ECU wants to see 1 volt on the Green/Red wire that goes from the TPS to the ECU so just back probe the G/R wire at the TPS plug w/the red meter lead and the other meter lead (black) to a ground such as the negative battery terminal or alternator housing and with the multimeter set to DC volts set the TPS to 1 volt and do this after the car is fully warmed up and the key to on with no accesories turned on. Also be careful not to press down on the adjustment screw when turning it or it will cause the voltage reading to fluctuate.

Seoul Seven

to 1 volt? ok. ill try ttat. but whats the difference from 1k ohms that aaron cake suggests?

satch

iTrader: (1)

I stick to the method/value that the ECU wants to see per the FSM so I'm not familiar with other methods.

arghx

iTrader: (3)

The ohm value required to reach 1 volt changes as the sensor ages. Basically there is higher resistance on older sensors. The ECU is looking for volts, not ohms. I use ohms to check if the sensor is bad or not but I use volts to actually adjust it.

Aaron Cake

iTrader: (1)

1K, not 1 Ohm. Very big difference.

Also, the car needs to be fully warm or the cold start cam disengaged. Otherwise the throttle blades are held open.

Seoul Seven

1k? so...i probably shouldnt have it tightened down all the way huh..

will it reach 1000.00 ohms? mines read 3.345 ohms when i tested it before i started messing with it.