Hlvo13

howdy all, I've been struggling with my 89 formula and its running ruff im getting the the throttle position sensor code and ive already put a new sensor in it. the sensor is putting out enough voltage so im at a loss any ideas, im starting to truly get desperate.

no new tires

Did you reset the ECM yet?

Hlvo13

yah I disconnected the batter, reconnected it, then fired it up the second you turn it on that code pops up

vetteoz

iTrader: (13)

Which code ; high or low ?

Be aware
A code is for a fault SOMEWHERE in a system ;NOT that the sensor of that system is actually faulty.

You have to work through the fault diagnostics for that code ; could be a power , wiring or ground problem .
Which is why you identify the actual problem 1st before throwing $$$ at it in the hope it goes away

no new tires

How long did you leave it unhooked for. It needs to be a unhooked for a few minutes to reset.

rusty vango

yeah ,like hey there might be something wrong .but were flintstone tech so .we really don't know. ok. enough with the "humor" EVERY PART of your TPS system needs to be looked at. twice. its the bane of our beloved 3rd gens . enough to drive you bat poo. I know but good luck

vetteoz

iTrader: (13)

And the system diagnostics on the latest cars are no different.
They only indicate a problem seen in a system , with a flow chart on how to identify the problem
They don't tell you what is actually wrong and give you the part # needed to fix it

paulo57509

After you installed the new sensor did you bother to adjust it to specs with the throttle closed?

You only mention it's putting out voltage.

Hlvo13

What do you mean?

IROCThe5.7L

https://www.thirdgen.org/forums/tech...ml#post5747674

2nd post from the top.

86T/A_Ram_Air

The last couple of TPS' I have seen new are of the non-adjustable variety.

no new tires

all you really need to do is "center it out" on the bolts.

(it needs to be straight up and down with no angle)

rusty vango

uh, no. you HAVE to adjust it for .5v at idle and the voltage should go up smoothly to near5v at WOT

vetteoz

iTrader: (13)

Really handy having newbies handing out potentially wrong advice

Need to state what year you are talking about ; not all are the same.

85 - 89 have to be set to a certain V value as stated above
90 - 92 are non adjustable and the ECM uses a different method to set the base value

no new tires

New account, Iv been a member for 7-8 years and I know what im talking about.
88 IROC-Z
My car ran wrong and threw a code when it wasn't centered. But then again my car is a little "weird" from the factory...

TTOP350

iTrader: (8)

This is correct.

Hlvo13

I thought I had, it's an 89 tpi 5.7

vetteoz

iTrader: (13)

I suspect ( actually I know ) if you read the TPS section in your FSM it will say different

The procedure is well documented on here and other online sources

https://www.thirdgen.org/tpimod2

http://www.iroczone.com/2009/10/adju...on-sensor-tps/

tonys91rs

iTrader: (17)

I had been having issues with my 305 tpi as well. it idles fine but a little gas ad it studders and pops. I switched out the tps for another one and adjusted it as it read in the articles provided above. No effect. I came across this thread and read that 90-92 are non adjustable. I have a 92 tpi. could this be why im still having the issue? I thought all tps were basically the same?

vetteoz

iTrader: (13)

They are but are setup differently

The '730 ECM used in the MAP cars uses whatever voltage it sees when the key is 1st turned on from the TPS as it's base value ; hence the non adjustable TPS on those engines
The MAF cars require the TPS to be set to the prescribed value

tonys91rs

iTrader: (17)

I need to switch back to a non adjustable tps in my car. I have the 730 ecm and map. what should the voltage be at turn on, or how do I test this type of tps to see if its correct or defective. im not getting any codes on it, before or now

86T/A_Ram_Air

It doesn't matter what voltage is at. The ecm uses whatever voltage its at on startup as its base reference. As long as the voltage goes up smoothly its good

Hlvo13

i just remembered the first problem this car had was the engine coolant fan wouldn't shut off. it lead to the battery dying, then the ignition relay went out, then the fuel pump would randomly not work so I replaced that, and now its something in the throttle position sensor's loop. could any of this be related? could it be the manifold air temperature sensor? or the coolant temperature sensor? im only getting the tps code

jazzdadss

What code is it?

Hlvo13

43 I believe,

jazzdadss

May need to double check, I show code 43 is for Electronic Spark control.

jazzdadss

I show code 21 for TPS Voltage High and code 22 TPS Voltage low.
Mitchel 1 refers to it as a 5.7 PFI. Even though it is TPI.

Hlvo13

I show that 43 can be tps, knock, or low voltage, but for the low voltage what should I do? also those small Bluetooth code readers worth anything? the like 20 dollar ones that you connect to a smart phone or laptop?

jazzdadss

If you have a fax machine I can send you a flow chart?

Hlvo13

I don't but can you scan it in and email it? that would be really helpful

jazzdadss

I have no scanner sir. Sorry.

Hlvo13

its fine maybe I can find it on google, what should I look for?

jazzdadss

Pics from my phone.








Hope this helps.

Hlvo13

thank you this should really come in handy

Hlvo13

So quick update I got the new tps and dialed it in and the check engine light when off after I reset the car. It runs fine up until about 1800rpm then it misses like crazy and the tac jumps to 7000rpm. Then when it gets to about 2100rpm the tac drops to where it's supposed to be and the engine runs fine, I took off my distributor cap and there is buildup in it along with black carbon marks on the center also the rotor is pretty worn. The shaft itself is pretty rusty but turned alright. Could the cap be the issue? It is also running pretty rich from the smell

TTOP350

iTrader: (8)

Sounds like you need a tuneup.

Hlvo13

Yah I might aswell