I have a 98 z and just replaced the tps and iac and slotted my tps to adjust it. I can't find any information on what wires to check and what specif voltage i should have. I adjusted it enough to start cold but wanna make sure it's set a bit closer to what it should be.

 

You can either log TPS voltage in HPTuners or use a meter and check the TPS signal wire at the sensor to see what the voltage is.

I don't know what the voltage limit is at idle to kick a TPS signal high DTC.

FWIW, mine is .73v and I've never had an issue. It has a NW102 TB on it.

Is the car stock or modded?

 

Its cammed with 3 inch borla exhaust cold air intake was told its putting out 500hp when I bought it. I put on a new iac and now the idle hunts from 1000 to 1300 and back and forth and when i get into the gas it falls on its face then clears out. Wondering if my ecm tune may have gotten erased sitting all winter without a battery

 

No it didn't. That's not how it works. Once the tune is uploaded to the ECM, it will be there forever.

 

Thats what I thought. Im gonna pull my throttle body and try cleaning it just to make sure. Will dbl check my iac and tps voltage again to dbl check. Just weird how it has no check engine lite

 

Why did you replace the TPS and IAC to begin with?

Why did you have to slot the TPS?

What type of throttle body?

Do you have anyway to log it?

 

A dead battery can definitely corrupt a custom tune. The hunting idle and stumbling are classic signs of a bad tune. Your new IAC is probably fine. The problem is likely the ECM.

You need to get the tune checked. A shop with a dyno can see if the fuel and spark maps are wrong. They can reload the correct tune for your cam and mods. Don't keep driving it like that; you could cause damage.

 

Explain how a dead battery can corrupt a custom tune but not a stock tune? Both are stored in memory.

So has the tune went bad like a gallon of mile or is the PCM bad?

How are they going to reload the " correct tune" if they have never tuned it before?

Please stop talking about things you obviously know nothing about.

 

Are you directing that comment towards me or the gentleman who posted before. I have been a mechanic for 13 yrs and I know not having a battery shouldn't affect the tune. Just curious what could have caused my issues all the sudden with no lite.
like I said before I bought this car from a GM rep in Texas. He had it built.. he passed away a few yrs back and Im unable to find whatball he had done to it. Kinda my own fault for buyi g a built car and not doing it myself. I also only replace the iac motor it wasn't working. The tps is the one that was in the car when I bought it. The shop that did the car slotted the tps to adjust for the bigger cam

 

i was replying to the person that commented before you. I should have quoted him. I'm sorry for the confusion

 

No all good. Just sux for me I was a mechanic for years then lost pretty much every tool I own. So now hoping to find someone to help my issue. Im having a hard time here where I live finding anyone else willing to even hook it up to there scanner so I can atleast get a number reading on things. Ive been looking for a decent program for my laptop and just buy a obd2 connector

 

Are you having issues with it still? If so what kind?

Also, did you get a chance to check the TPS voltage?

 

Tps voltage is .67v my issue now after replacing a bad iac motor vent from the car holding at 3000 rpm to idle hunting from 1000 to 1300. And when I get into the gas it stumbles cleans out and revs good. I have a short video if interested in seeing and hearing it

 

You said the old IAC wasn't working, what exactly was it doing?

Sorry for all the questions, just trying to get an idea of how things went.

 

Well i suspected it was the cause of my initial issue of high idle sticking. When I pulled it to look and the pintle I notice a bunch of carbon build up so tried to clean it and didn't help so replaced it with a new one. The new one don't stick at 3000 rpm but now idle jumps from 1000 to 1300.. so I put the old one back o e just to dbl check and it went rite back to idling high and when I hit the gas it revs and takes forever to drop back down. I just don't understand how I have had the car for 3 yrs never had a prob now ot idles odd and has no lite. Im wondering if i should just replace the tps as well just as a precaution deal to eliminate it

 

In this day and age, it is very possible the new IAC is junk. I've read quite a few threads about people having issues with new IAC motors.

If you had the exact same problem with the new IAC, that would lead to believe something else is the problem but you obviously have a different one.

You putting the old IAC back in and having the same issue verify's that, IMO.

New doesn't mean good.

What brand is the IAC?

 

Ac delco i believe

 

Im also looking at the tuner pro download. Can you recommend if its good or not and and obd2 cable recommendation for my laptop

 

If any part of the flash memory gets corrupted, the PCM won't even boot properly. If the car still runs at all, the PCM's memory is not corrupted.