Turbonut

iTrader: (1)

Setting TPS:
Key on-Intially set the narrow range (adjustment screw) .75-1.25 , wide (no adjustment) .25-1.25
Then hook up meter to Check Connector (Positive lead into single, Negative lead alternately into each of the other 2 pins) and adjust until value in only one combination. If both have value, or neither register any volts, adjust accordingly. I assume you could use 2 meters, but my other meter was down at the house, so I didn't experiment.
Results:
'89TII-After playing around with a performance/idle (TPS & BAC) issue thought I would post findings.
After fixing BAC, routine cleaning, resistance, voltage, and TPS adj. to .99 volts, car idled somewhat better, but experienced a detonation in second gear @ 1/2 throttle. Back to garage to replace the TPS. Installed new, even though used, TPS and set narrow to .97, wide range .65. Took the car out for a test. Idle was still high @900/1000 and not as smooth as I would like, but not lumpy, or missing. On way home in fouth, accelerated and had 2 quick detonations @ 3/4 throttle. Once home checked TPS and still the same .99 and .65. I then hooked up meter to Green Check Connector.(Pos lead in single, Neg in each side of double, alternately) and found 10+ volts in each. Meaning both lights on Mazda tester would be on. With meter attached to Check Connector, I began turning TPS adjustment screw clockwise. After about 4 turns, the meter dropped to zero. I checked the other side and it had 10 volts. Tightened everything down, went for ride, idle down to 700/800 and as smooth as could be. A couple of performance test showed no problems.

ilike2eatricers

good write up.

Red 86 rx-7

How can I apply your TPS fix to my 86fc n/a?

Aaron Cake

iTrader: (1)

If you need 4 turns of the TPS screw to adjust things "properly", then there's something else seriously wrong. The proper procedure is below:

Adjusting the TPS is a simple maintenance item that should be preformed at any oil change. The benefits include better gas mileage, better performance and a smoother idle. Adjustment only takes a few minutes if you follow the directions below.

What You Need
· Ohmmeter
· Flathead Screwdriver
· Half an hour

How To Adjust
· Warm the car completely by driving for 20 minutes
· If your car is a turbo, remove the intercooler. Loosen the hose clamps on the inlet and outlet, remove the vacuum line, and then remove the four bolts (I believe 11 or 12MM). Lift off the cooler. Do this quickly so the car does not cool.
· Unplug the TPS. On 89+ cars, you want to unplug the connector leading from the lower TPS.
· Hold the TPS connector so the hump points up. Connect your meter between top connection and rightmost connection.
· Adjust the stop screw until the meter reads 1K (1000 Ohms)
· Plug the TPS back in
· If necessary, reinstall the intercooler. Don’t overtighten the hose clamps
· Drive the car for a few minutes, then repeat the procedure

Turbonut

iTrader: (1)

Well Aaron, I couldn't even remove the intercooler with a 10 mm socket (couldn't resist) and also why deviate from Mazda tester?
This procedure seems similar to adjusting narrow to 1.0 volts and leaving it at that point. You're allowing no compensation for wide variation. Four turns may be quite a bit in your estimation, but the car is perfect, and it only increased the volts to 1.27.

Turbonut

iTrader: (1)

Just got home from work and wanted to explain. I wanted to emulate the Mazda FSM and post for all who wanted to adjust the TPS in this manner, which may be easier for some. If others desire to use the resistance method, so be it.
Sorry I posted it!

*a*jones*

what if my car doesn't hold the correct voltage? when i get it set correctly as soon as i get back from a drive it's out of whack again. is there any way to fix it or do i have to buy another one?

Red 86 rx-7

Some posts In my search say to connect two LED's to a three prong coupler...1 red light 1 green...you want only one LED to light up.. Also ad a jumper wire to some other coupler near the front coil pack?????

RoninAutoBoX

The jumper wire near the front coil pack is to check for ECU error codes I believe. That is only if you get a check engine light.

Red 86 rx-7

I have the two LED test setup for my car My question is should the engine be off or running? 1 light when adjusted right? Sorry I only have 1 multi meter..I noticed when I have the car off Both lights are on...When I start the engine only one is lit when running...Also should I be using LED's with a built in resistor????

NA_VersionFC3S

The car should be off when doing the test. You notice how one of the steps is to remove the intercoller (if you have a TII). So obviously the car should be off.

Tim

RETed

1) Cause the stupid Mazda test procedure doesn't look for "dead spots" in the TPS travel, which could cause hesitations at any RPM.
2) Cause the stupid Mazda test procedure doesn't look for "overly high resistance" at full open, which could cause high RPM hesitations.
3) Cause it's a stupid Mazda test...


-Ted

Turbonut

iTrader: (1)

Your opinion, but if the TPS is bad it will not work properly even after you set to the correct resistance. Is this not correct?
Naturally you need to check the TPS through it's travel if problems persist after initial setting.
At least if I'm having a problem, I can check Green Check Connector without removing the intercooler etc.
Had car out last night, pulled strong as ever, right up to 6500 and 9.5 lbs boost. Felt great. Dave at KD hit the problem right on the nose. He had said the TPS was all over the place after USING THE MAZDA TESTER and he, as usual, was right.
My opinion.

RETed

But when I check idle, WOT, and progressive opening, that eliminates almost all problems that could be associated with the TPS. If it clears all those tests, I would look elsewhere if you're running into problems. Care to show me how using a pair of lights and/or looking at voltage?


Sure, but how do you do that with a pair of lights?


Sure, but I can also remove my intercooler in 5 minutes, and that's not a big deal for me. You can run a telltale on a boost gauge while on the track, but that only tells you what your max boost was - wouldn't a full datalog of your boost levels be a much useful tool? It's a matter of relativity - just because it's good enough for you don't assume it's fine for others.


Anyone who has to resort to a MAZDA TESTER has a problem using a simple DMM - I would seriously worry about that...


-Ted

pistol

Turbonut Pm'd you.

HAILERS

****what if my car doesn't hold the correct voltage? when i get it set correctly as soon as i get back from a drive it's out of whack again. is there any way to fix it or do i have to buy another one?******

The engine has to be HOT. Fully warmed up. If the tps is set.....then you go back to look again an hour later...the reading will not be the same. That's due to the thermowax moving the linkage. Always set the tps with a fully warmed up/hot engine and if your going to check it at a later time make sure the engine is fully hot/warmed up. If you don't the readings will be different. That is normal and to be expected.

Templeswain

I just tried aarons' proceedure.

I have two tps sensors as he indicated for 89+ cars.

The wires that go from the lower tps are black/red
green/red and solid orange.

So I used the DMM, and I get 3000K-4000k. The car likes to idle high around 1200, to 1500.

Turning the screw only increases the resistence, but will not decrease it.....?

Crappy tps or am I doing this wrong?

jacobcartmill

iTrader: (6)

which TPS (narrow or widerange) do i set to 1.000 ohms?

RETed

Narrow (black and green wires) and it's ONE THOUSAND ("1k") ohms.


-Ted

dubrc

last time i checked, it was worth about $260 CDN, so I'd use the resistance test and make sure that it is not working before dropping that much dough. I was able to find one at a wreckers for a couple bucks, but there's no guarantee it'll be in better shape than your previous one.

Molotovman

iTrader: (49)

What connector are we talking about, i dont understand how to do this locationwise.

ViperDude152

another right up
http://www.racingrotary.com/tps.htm

Turbonut

iTrader: (1)

Above post decent except for the part if not 1k ohm replace the tps. The Mazda range is , don't quote me as I don't have the FSM handy, S5 .75/1.25k ohms as a starting point, then adjust the tps via Mazda check connector. In my experience starting at 1k ohms, or as some say 1 volt, then do the adjustment with the Mazda connector the best bet. Also with engine off and meter connected, run the tps through it's range and make certain no low points or spikes. Must be smooth.
Just a FYI-The tps can be adjusted with engine cold as long as the fast idle cam is disengaged. I use a screwdriver to hold it down as it is annoying to remove the intercooler and work on it at times when hot.

Aaron Cake

iTrader: (1)

That page scares me. The test lamp method SUCKS. The ONLY accurate way to set the TPS is via resistance.

JKM

I adjusted mine a few weeks ago following Aaron's procedure. After I finally got it set right, it made a WORLD of difference. Before I adjusted anything the resistance reading was 2k ohms