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nerd racing

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Posts: 4,219

#1 [url]

Feb 17 09 7:24 PM

our cars don't have map sensors, so you can't check that

Our cars have MAF sensors, the big one on the air box.

"In a perfect world all the geeks get the girls"

1995 Ford Aspire 3 Door Black, (B8 F-series)---> RIP
1997 Ford Aspire 3 Door Teal ---> Sold '08
1996 Ford Aspire 5 door Green ---> Parted wouldn't hold her oil
1994 Ford Aspire 3 door Red ---> Former BP, V6 Swapped... Rusted Out...
1995 Ford Aspire 5 Door Blurple --> Sold '11 No Room...

1989 Ford Festiva L 4 Speed Carby Model --> Soon to be an Abomination!
1990 AWD 5 Speed Mazda Protege Black -->(BP GTX Trans) Daily Driver/Donor Waiting to Happen... Soon to be BP+T


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#3 [url]

Feb 17 09 11:10 PM

You can't effectivly check for voltage outputs...all the sensors connect to the computer and you are liable to cause more damage than good. Most problems with one of these will give a fault code. However if you want to check the TPS I have included ops check and adjustment. What makes you think you have a problem with one of these?


The checkout and adjustment proceedures for the TPS are:
1. Disconnect plug from TPS and connect a digital ohm meter between terminals A and B of the sensor.
2. Turn the throttle lever to the Wide OPEN Throttle (WOT) position and check the resistance reading on the multimeter. The reading should be approximately 5K ohms.
3. Turn the throttle lever to the fully CLOSED position and check the reading on the multimeter. The reading should be below 1 ohm.
4. If the resistances are not within the specifications, adjust the TP sensor as follows:
- Loosen, but do not remove, the TP sensor screws.
- With the throttle lever in the closed position, adjust the TP sensor until the multimeter reads below 1 ohm.
- Turn the throttle lever to the WOT position and check the resistance. The resistance should be approximately 5K ohms. If the TP sensor cannot be adjusted to specification, the throttle body must be replaced.
5. After the TP sensor resistance readings are to specification, tighten the TP sensor screws to 1.6-2.3 Nm (14.2-20.3 lb in) .
Connect the TP sensor electrical connector.




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#4 [url]

Feb 18 09 9:17 AM

here is what happened coming home from work car stalled idling tried starting car nothing sprayed starting fluid on filter fighted with car got it started got it home. stalled twice pulled plugs cleaned they smelled of gas and wet checked the dist cap nothing saw nothing car starts drives some completely dies when loaded if i let off gas it re idles check engine light on for 1-2 years about 10,000 miles for more

I will check the tps i am leaning to the maf

Can i have the resistance for the coil(s) i was told they are in the dist

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#5 [url]

Feb 18 09 12:33 PM

you can check any sensor without damaging it.

You can check the resistance on the sensor by unplugging it, TPS, for example, hook a meter up, turn the throttle from idle to wide open, and resistance should change slowly and steady, without jumping around all crazy.

turnign the key on, the wiring harness going to the sensor should be putting out 5 volts, maybe 12. depends on the application.

then you can plug the wiring harness back into the sensor, take a meter, (carefully) and tap into the wires, and turn the key on, should be getting voltage, and turn the throttle, and voltage should change, one way or the other, slowly and steady, bit by bit, without jumping around.

Only exclude is the oxygen sensors, as the oxgygen passing over the sensor generates voltage, those need to be tested with great care.

Some sensors you can do outside the car, like with a temp sensor, use a LIGHTER, not an acetylene torch) to change the heat, and should read difference resistance, or if connected to the computer, change the voltage.... etc etc.

but do it if your familiar with digital meter work. And you can damage the meter if done wrong (testing resistance on the circuit if voltage is present).

good luck.

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#6 [url]

Feb 18 09 3:20 PM

QUOTE (nerd racing @ February 17, 2009 07:24 pm)
our cars don't have map sensors, so you can't check that

Our cars have MAF sensors, the big one on the air box.

actually if hes an aussie, and has a WF festi he actually does have a MAP sensor not a MAF, like I do

user posted image

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bluesneaky

Executive Member

Posts: 490

#7 [url]

Feb 18 09 3:45 PM

QUOTE (MJG @ February 17, 2009 11:10 pm)
However if you want to check the TPS I have included ops check and adjustment. What makes you think you have a problem with one of these?


The checkout and adjustment proceedures for the TPS are:
1. Disconnect plug from TPS and connect a digital ohm meter between terminals A and B of the sensor.
2. Turn the throttle lever to the Wide OPEN Throttle (WOT) position and check the resistance reading on the multimeter. The reading should be approximately 5K ohms.
3. Turn the throttle lever to the fully CLOSED position and check the reading on the multimeter. The reading should be below 1 ohm.
4. If the resistances are not within the specifications, adjust the TP sensor as follows:
- Loosen, but do not remove, the TP sensor screws.
- With the throttle lever in the closed position, adjust the TP sensor until the multimeter reads below 1 ohm.
- Turn the throttle lever to the WOT position and check the resistance. The resistance should be approximately 5K ohms. If the TP sensor cannot be adjusted to specification, the throttle body must be replaced.
5. After the TP sensor resistance readings are to specification, tighten the TP sensor screws to 1.6-2.3 Nm (14.2-20.3 lb in) .
Connect the TP sensor electrical connector.

Nice quote from the SM manual but it dont work. fordaspire/angryfire.gif

35 years in electronics and I can tell you there aint no 5k single turn potentiometer made that you are going to read that low end resitiance on. It will just apear as a short.

I tried and tried and tried to make the instructions work (despite my electronics background) but it just doesnt. I'd love to say go by the manual always but on this one I am 99.9% sure its a typo that is repeated over and over. You just cant do what they call for. I even tried diffrent TPS's and diffrent cars. By the time the pot reads under 1 ohm you cant set the high end requirement.

One thing for sure that is rock solid advice, before you move that TPS - Mark it! That way if I am right and the procedure to set it is bogus you can at least put it back where it started from if it is not the problem. fordaspire/banana.gif

Ziggy 1 --- '95 white 2dr, 5sp, a/c added, 252k, 43 top mpg (still got 'em)
No Name --- '95 teal 2 dr, 5sp, 98K, bad clutch, sold it b4 I named it
Ziggy 2 --- '95 white 2dr, 5sp, a/c 147k split rear seat, 49.3 top mpg (deceased, mortally injured in towing accident 2008)
Kermit --- '95 teal 2dr, 5sp, a/c 103k, upgraded interior package - the daily driver now
(Had 2 1988 Festivias in the '90's. Over 200k on them too)

All pulled "Trapper" the '89 kamparoo camper on the back roads I should'a been drivin' my jeep on (4x4 aspire??)

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bluesneaky

Executive Member

Posts: 490

#8 [url]

Feb 18 09 3:47 PM

PS:

I got a handfull of TPS's still left in my garage from this learning experince...

Ziggy 1 --- '95 white 2dr, 5sp, a/c added, 252k, 43 top mpg (still got 'em)
No Name --- '95 teal 2 dr, 5sp, 98K, bad clutch, sold it b4 I named it
Ziggy 2 --- '95 white 2dr, 5sp, a/c 147k split rear seat, 49.3 top mpg (deceased, mortally injured in towing accident 2008)
Kermit --- '95 teal 2dr, 5sp, a/c 103k, upgraded interior package - the daily driver now
(Had 2 1988 Festivias in the '90's. Over 200k on them too)

All pulled "Trapper" the '89 kamparoo camper on the back roads I should'a been drivin' my jeep on (4x4 aspire??)

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#9 [url]

Feb 18 09 11:09 PM

wtf? that makes no sense...
i tested the one on my z71, my dakota, the aspire, along with my other 10 cars....

meter will read all the way down to 1 ohm easily.....

mine reads near zero, and 4.98k at the extreme other....

if you take the return spring off it's alot easier to try and fine tune the position at the extreme's... i did some rigging and used a mechanical clock to sllllowwwllly turn the sensor so i could see if there were spikes/jumps in the resistance, making sure it changes smoothly.

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#12 [url]

Feb 20 09 8:08 AM

if your using a DECENT digital meter, you should be able to read 0.1 ohms easily.
If you short the meter leads it MUST read a near zero, otherwise whatever reading you get when shorting the meter leads, add that to your final reading, since your leads are adding resistance to the circuit...

and don't be using the $3.99 ones from harbor freight. please use a decent one, 50-60$


when i go up to the shop today i'll take the pictures of me taking the reading of the TPS on the car i'm pulling the gear box out of....

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bluesneaky

Executive Member

Posts: 490

#13 [url]

Feb 23 09 4:59 PM

meters read 1 ohm easily, thats not what i am talking about. 5 k pots will also go to 0 ohms easily too. its the procedure that is goofed. I will document when I finish the trip I am on if someone else doesnt beat me to it.

Ziggy 1 --- '95 white 2dr, 5sp, a/c added, 252k, 43 top mpg (still got 'em)
No Name --- '95 teal 2 dr, 5sp, 98K, bad clutch, sold it b4 I named it
Ziggy 2 --- '95 white 2dr, 5sp, a/c 147k split rear seat, 49.3 top mpg (deceased, mortally injured in towing accident 2008)
Kermit --- '95 teal 2dr, 5sp, a/c 103k, upgraded interior package - the daily driver now
(Had 2 1988 Festivias in the '90's. Over 200k on them too)

All pulled "Trapper" the '89 kamparoo camper on the back roads I should'a been drivin' my jeep on (4x4 aspire??)

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#14 [url]

Mar 3 09 5:02 PM

also if it is warm out it starts better than below freezing

it will drive okay (not right) untill the car warms up

also i do have a hole in the exhaust the the resintator but disconnected

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bluesneaky

Executive Member

Posts: 490

#16 [url]

Apr 3 09 3:45 PM

EXACTLY!!!! Thats my point.

You are reading it correctly and everyone else and the SM is WRONG. ( i know pertty bold of me but I also am pretty sure of myself on this)

It is a misprint that is carried over to the haynes manual as well. And with all the fancy meters people are getting with auto ranging they arte not reading thier meter right.

All the whopdala about reading below 1 ohm is sensless crap (sorry guys but on this one it is) And like I said I've been doing electroncis way to long to be wrong on this one.

The thing will not go to bellow 1 ohm while on the car. Aint no way! And even itf it did a single turn 5K pot has no senesitivity below 1 ohm, that would be nuts. that is esentialy a dead short in relationship to 5k on a single turn pot. (and this is not even a full 360 one turn pot even)

If the manual read below 1k it would be something you could set but it can not be set to below 1 ohm. I challange anyone to do it.

If you set it to below 1k things begin to be beliveable. However 2 years ago when I got ziggy#2 i did extensive work trying to get it to preform equal with Ziggy #1 on the exact same road and the exact same conditions. #2 got crapy MPG compared to #1 and I was determined to get at least the same as I had in #1 since they were identical cars. Heck if anything #1 should have gotten slightly less given ring wear with the high miles and #2 with low miles.

I checked brake drag, front drive train, air filters, spark plugs, wires, types of gas, timing, and on and on. Nothing made a diffrence. I even took the a/c belt off thinking it could be adding drag. Still no diffrence.

So I started swaping parts I couldnt check like the MAF, temp sensors, O2 and so on. Still #2 got way less MPG. I changed the TPS (marking it's placement in the swap) still no change.

Nothing made #2 get good MPG. Finaly I read all I could about the inputs to the computer. I started disconecting inputs one by one then replacing them from the computer on #1 trying to get it to match #2. Nothing worked. I did learn a whole lot about how the computer processes the info it gets and how it effects the engine's running though.

The major thing I found was that although the intputs to the computer help it fine tune the engines running it would not prevent it from running decently enough given only one failure of any one component. It also demonstrated that things like the O2 sensor are slow to react devices on the OBDI aspires. Likewise with MAF and temp.

Basicly there was not much left that could instantly effect the fuel mixture having eliminated the MAF & o2 with the slow reaction. The only thing left was the TPS! It gives an instantanious reading electricly of precisely where the throtle is and hence is the major player in determnining how much fuel is to sent to the engine based on that instantanious amount of air reaching the engine at that point in time.

So I tied to set it by the book and no luck. Just what you have run into. I tried and tried to do it by the book since both books said the same thing! Anyway I gave up doing it by the book and went with my own deduction that it was a misprint and should read 1K.

Wow did it make a diffrence!!!! fordaspire/460.gif All of the sudden the MPG jumped! I was able to dial in just what I wanted. This is the golden nut to turn to get MPG up. If you tweak with this and distributor postion just a little off what it calls for you can jumpstart the MPG without getting to predetonation or too lean of a mixture.

I was unsure of posting this at first becasue there was a chance I was running to lean and was going to pay with a burned valve so I kept quiet. But after a total of 2 years and 50,000 miles (a good part of that pulling a trailer) I can safely say the mixture was not too lean and I did not burn a valve.

If you are getting lower than 38MPG (w 5sp of course) and have done the normal remedys to no avail I would highly recomend you look to this adjustment. Some monkey may have been into your car before you trying to set it to below 1 ohm and left it as low as he could get it rather than where it should be.

I welcome comments and challanges on this topic.



Ziggy 1 --- '95 white 2dr, 5sp, a/c added, 252k, 43 top mpg (still got 'em)
No Name --- '95 teal 2 dr, 5sp, 98K, bad clutch, sold it b4 I named it
Ziggy 2 --- '95 white 2dr, 5sp, a/c 147k split rear seat, 49.3 top mpg (deceased, mortally injured in towing accident 2008)
Kermit --- '95 teal 2dr, 5sp, a/c 103k, upgraded interior package - the daily driver now
(Had 2 1988 Festivias in the '90's. Over 200k on them too)

All pulled "Trapper" the '89 kamparoo camper on the back roads I should'a been drivin' my jeep on (4x4 aspire??)

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bluesneaky

Executive Member

Posts: 490

#17 [url]

Apr 3 09 3:53 PM

QUOTE (AtomicAlero @ March 31, 2009 05:59 pm)
i tested the tps between all contacts and did not get anything under 1.1 K ohm and nothing cloase to 5K ohms and the voltage peaked in the middle

PS

if you want to see the 5k go between the outer terminals with the plug off the TPS. You should see the 5k then. The center terminal is the wiper of the 5k pot.

BTW, You should not be reading voltage but ohms. do the test with the engine off and plug off the TPS.

My final setting for TPS in closed postion was 1.4k This with the timing tweak gave me the 42-48 MPG (44 advg.) with no long term effects. I was intrested in MPG upmost and low end torque for pullingwithout damaging the engine in anyway that woud effect its long term life span.

Sneaky

Ziggy 1 --- '95 white 2dr, 5sp, a/c added, 252k, 43 top mpg (still got 'em)
No Name --- '95 teal 2 dr, 5sp, 98K, bad clutch, sold it b4 I named it
Ziggy 2 --- '95 white 2dr, 5sp, a/c 147k split rear seat, 49.3 top mpg (deceased, mortally injured in towing accident 2008)
Kermit --- '95 teal 2dr, 5sp, a/c 103k, upgraded interior package - the daily driver now
(Had 2 1988 Festivias in the '90's. Over 200k on them too)

All pulled "Trapper" the '89 kamparoo camper on the back roads I should'a been drivin' my jeep on (4x4 aspire??)

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#18 [url]

Apr 6 09 6:26 PM

i erased the codes after trying different maf sensor and the check engine light is not coming back on i ran the car for 10-30 minutes and made it mess up. the repair manual i have shows how to test the votlage of the tps with the key on and engine off at closed,1/4, half, 3/4, wot. does that work . I need to fix the car quick

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bluesneaky

Executive Member

Posts: 490

#19 [url]

Apr 18 09 2:11 PM

From the sound of it you are reading the haynes manual for setting the TPS. It is just about as bad as the Ford SM. Haynes has you check the voltage with a volt meter in the first steps then if it doesnt meet spec they magicly toss that meter out the window and start using some unspecified "meter" that only measures continuity as a open or short! What the heck????

The Ford manual never has you check with the ignition on, they do not have you check voltage. It has you check resitance. in a nutshell, 5k for wide open throttle and then the typo of under 1 ohm which should be under 1k in the idle postion.

Haynes manual is bogus because if you account for only continuity when measuring a variable resitor, the "yes/no" point for deciding when there is or is not continuity is dependent on the tester you are using. For example, is 1.8k ohms called no continutity or is it called continuity? Just depends on your particular tester and that is no way to decide. It will vary from one inturment to the other.

The way to set it is using a ohm meter. Rotate the TPS so that you do have 5k from the Ref to Sig as they call it in the haynes manual or center pin to outside pin on the car and then that same test should read 1k or under when you do it with the throttle in the iddle postion. Both tests are preformed with the car off and the conector from the wiring harness removed with testing preformed on the TPS itself.

I personaly have found that a iddle setting of 1.4k and WOT at 5k is fantastic for fuel economy without running to lean.

The TPS is the big kahoona for the engine control unit for deciding how much gas to send into the cylinder via the injector. It only makes sense, if the throttle is closed dont inject much fuel, wide open, dump all it can in and find out where the throttle is by the throttle postion sensor. From the contol units perspective this is a voltage from this TPS of from 5v to about a half a volt. The 5 volts sent to the TPS is varried (or lowered) by the variable resitance of the TPS in what ever postion it is in. This lowered voltage is sent back to the control unit and the amount of time the injector is opened is varried accordingly.

Clear as mud now?

Set it for between 1 to 1.4k in the closed postion and make sure it reads 5k when wide open as well. Thats the place to have it!

Ziggy 1 --- '95 white 2dr, 5sp, a/c added, 252k, 43 top mpg (still got 'em)
No Name --- '95 teal 2 dr, 5sp, 98K, bad clutch, sold it b4 I named it
Ziggy 2 --- '95 white 2dr, 5sp, a/c 147k split rear seat, 49.3 top mpg (deceased, mortally injured in towing accident 2008)
Kermit --- '95 teal 2dr, 5sp, a/c 103k, upgraded interior package - the daily driver now
(Had 2 1988 Festivias in the '90's. Over 200k on them too)

All pulled "Trapper" the '89 kamparoo camper on the back roads I should'a been drivin' my jeep on (4x4 aspire??)

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