invinciblejets

I own a 1990 vert.. I'm having issues with misfiring seems to be random tho it started out when the the car reach operating temp it would misfire for the first 5 mins of driving the would go away and be fine.. that started maybe three weeks ago.
Since then it's gotten much much worse so now it runs fine during first ten mins of driving then after that it just starts misfiring like crazy everytime I touch the gas....

I've replaced since this incident:
Plugs
Plug wires
Air filter
Fuel filter ...

So I'm kinda lost and now thinking it's a fuel issue rather than my initial thought of spark.....

Could tps have somthing to do with it from what I read tps and misfiring don't seem to go together..

Maybe a ground??

Thanks in advanced..

invinciblejets

Can someone dumb down the tps adjustment for me?....
I have multimeter....what prongs do I put to what wires?

I can only find adjustments directions for the s4 3 pin connection my s5 has 6...

satch

iTrader: (1)

Green/Red for voltage reading and negative battery terminal for ground. Same as S4.

invinciblejets

Thank you satch ...Will report back shortly

monty11ez

The easy way to check it on an S5 is to take a look at the green 3 prong plug near the air box. Put your positive lead in the bottom. Use the negative lead to check the left and right side sockets. Turn the ignition to the on position. The right slot should be around 12V and the left should be some very small value. If both are practically zero tighten the adjustment screw. If both are 12V then loosen.

invinciblejets

Thanks will try the air box one.........the tps green/red wire I can't probe right or somthing just says zero....

invinciblejets

Still reading zero no matter what?

satch

iTrader: (1)

Are you placing the meter probe into the back of the plug and making sure it is snug. And the plug needs to be plugged in and w/key to on.

invinciblejets

Wont I destroy the rubber plug around the wire?

satch

iTrader: (1)

Rubber? It should be plastic. If you don't place the meter into the back of the plug then how would it be possible to measure the wire?

invinciblejets

Sorry I really have no clue I'll try it

ghost1000

iTrader: (1)

I somewhat remember looking for a 1v reading at the TPS while runing and connected at idle but its been awhile. If its temp related I would start looking for vacuum leaks. Spray around the intake with WD-40 and c if it clears up.

Check the vacuum lines and the maps. Sometime returquing manifold bolts will fix the problem but don't go too tight, that's really a temp solution.

invinciblejets

Still nothing...... getting zero.. so maybe tps is dead???

Forgot to say I checked vacuum and compression

satch

iTrader: (1)

Are you sure you have the key to on?
Are you placing the red meter lead to the G/R wire of the TPS w/the TPS plugged in?
Are you placing the black meter lead to the negative battery terminal as the ground source for the meter?
Do you have the meter set to DCv?
Can you properly get a voltage reading from the car battery to prove that the meter is not only working, but to prove as well that you know how to use the meter properly when taking a votage reading?

invinciblejets

I know the dmm works and yes I'm sure I was thinking of cutting the wire right at the plug testing then putting it back it plug..

And every time I test it says zero.. but It makes a noise like when your connecting the battery terminal and it zaps and crackles a little.. maybe a loose ground Somewhere?

satch

iTrader: (1)

Why are you connecting the battery terminal? The Brown/White wire (two of them) at the TPS should have 5 volts or so w/key to on. Does it? And do you have the key to on? I think I've asked this three times and counting. And just simply shove the meter lead into the back of the plug like everyone else. And is the TPS plugged in or not?????????????????????????????????

invinciblejets

I was comparing the sound to the battery terminal....... I did not do anything with battery terminal but put negative lead on it....

I've done everything you have said as you said and it did not work...

I know ask what does It mean when tps reads nothing!?

invinciblejets

Sorry for stealing this pic for example

All of the wires where they go into plug have rubber grommets I absolutely destroyed mine shoving the positive lead from dmm in there still with no reading

satch

iTrader: (1)

Look at the first diagram in the link provided and focus on the top left where it says Throttle Sensor and tell me those are the wires in the diagram which you provided a pic of. That's not the TPS plug for starters that you have pictured. Secondly, do you know what the sensor looks like? The wires coming out of the sensor are short in length and should lead to the proper connector.

https://www.rx7club.com/2nd-generati...wires-1013741/

S5 TPS pic:

http://www.mazdatrix.com/86-92Electrical-Engine.htm

invinciblejets

I don't understand are you saying plug In the pic I provided is not the one you stick the + probe?

satch

iTrader: (1)

Yeah!

invinciblejets

Which plug then that only one attached to tps?

satch

iTrader: (1)

I provided a diagram which indicates what the proper wire colors are. The wires coming out of the TPS are the exact same colors that should be plugged into it. G/R goes to G/R, B/G goes to B/G, Br/W goes to Br/W and so on. I can't be your eyes such that you need to do this yourself.

invinciblejets

So this need to test the green /red wire on the plug on main harness that plugs into tps not other way around?

satch

iTrader: (1)

A G/R wire from the Emission harness plugs into a G/R wire from the TPS. Either wire can be tested as long as the proper G/R wire from the Emission harness is mated to the TPS. I'll let you figure out the rest.