I replaced my TPS last night.

Anyone know what the low/high readings should be ? I managed to eek out a .70 and 4.49. I don't know what the factory idle and WOT readings should be ?

It seems to run much better with the new unit. The tip-in and downshift/idle characteristics have improved. It accelerates now without any jerky hesitations of old.

thx,
RP.

 

I believe the nominal # is .56volts at idle. The '90+ TPS sensors are not adjustable like the '85-89 units are. You can, however, drill the holes out to make it adjustable.

 

.56 ? I am off by a country mile then at .70. That can't be too good for the setup or does it matter all that much ?

How and what do you drill ? I can practice on my old unit.

thx in advance,
RP.

 

Drill holes to make it adjustable??? WHAT!!! Richard, do not drill any holes as that is totally not necessary. The minimum should be .57 and 4.5 at WOT. They don't have to be exact, but as close as possible. If anything you wanna worry about the min more as this effects your off-the-line performance. With it at .70 you are starting off waaaay rich and that will only bog you down. I'm surprised your not getting a code thrown actually. Just keep playing with it, adjusting up and down...and in and out. The i&o will help you adjust your max and the u&d will help you fine tune your min. I managed to get mine to at .57 and 4.43. Of course it's a little easier with the laptop and scanning software.

 

Yeah, drill holes. The '90+ versions have next to no adjustability. rather than slots they have holes that are just big enough for the screws. You will want your TPS to be adjusted to .54-.56 at closed throttle. That can't allways be reached due to production tolerances.

 

I would think if the sensor was made that way for a reason. I doubt that the factory drilled holes when the car was put together to adjust it. There's gott be a way to adjust it with making mods like that.

Palric: Your welcome to take a trip out to Hamilton on the weekend if you want and we can see if we can get it adjusted.

 

Hey IROCKER muchos gracias for the offer but AcceldZ is right -- there is butt squat little adjustment in this thing.

No kidding I get a fraction up and down and NO in and out. I can tell immediately what Paul is saying you can see on my TPS where they used to be 'drilled out' or can be drilled out -- if you know what I mean -- and now have molded plastic.

There must be a diff between the '87s and '90s (mine is a '91) ?
I'll try it on my old one first.

IROCKER if you are running at 4.43 does that not hurt your WOT ? Curious, I thought 4.5 was the signal to the ECM to disregard the O2 sensor ????

thx all,
RP.

 

WOT is between 90 to 100%, so anything above 4.05V the ECM will kick into power enrichment mode.

I still think there has got to be a way to adjust it better than drilling. I'm not trying to call Paul a liar, that's not what I mean. There has just got to be a way.

 

The only way to make the 1990+ TPS sensors truly adjustable is to elongate the bolt holes on the sensor. It's a standard practice at GM dealerships. That's where I learned about it.

 

Now that's just plain stupid!!! Design and make a part that requires adjustment to function properly, but forget to design it with the adjustment capability...that makes a lot of sense. Ya gotta wonder what goes through the minds of some of the engineers!

Could you order the TPS from a early third gen? I have a spare one if you wanna try.

 

Hey IROCKER thx for the offer but the new one is in as of last night with elongated holes. I was able to get:

low -- .57v
high 4.41v

and it seems to drive pretty good. I was able to get the low read or idle down to .48v but that pushed the WOT down to 4.28 and I wasn't sure if that was OK ? So I dialed it back and so far so good.

AcceldZ & IROCKER:
To clarify -- there was a way I could get the original un-modified and virtually non-adjustable TPS to read below .70v and that is to back off the throttle plates by unscrewing the adjuster. This drives the actuater bar on the TPS vertical (up) which pushed it down volt-wise and I could get the .57v I needed for idle and as much as 4.38 for WOT. The thing is the throttle plates were backed off so far that they were binding on the throttle bores and the car was totally IAC driven at under 1000rpms. This made for some 'jerky' stopping and poor driving and I did not like it.

thx all,
RP.

 

I have a 91 Z-28, how do you check the voltage on the TPS? Thanx

 

Here's the easiest to follow article i've ever found...............

http://www.sethirdgen.org/tps.htm

 

dont forget to check if the increase in voltage is linear..The voltage should go up gradually as you throttle..It might be up to spec ojn both ends but have flat spots or misses in the middle..Make sure your IAC and timing are wertup right before you do the TPS as these things affect the curve..

Daz

 

I agree with Daz...you don't want any flat spots as the TPS goes to WOT. AS for the voltage... It sounded great where you had it to begin with. Was it running rough at those setting of .70-4.49??? IF so like Daz said the timing, and the IAC could be causing you some probs. I too agree with Irocker. I would not drill holes in that thing. Like I said the original setting you posted didn't sound all the bad. IMO

Keiran

 

Holy ****, the only way to make the '90+ TPS adjustable is to elongate the slots. This is not some backyard ghetto rig solution. It's what GM does to make the '90+ TPS sensors adjustable. Not that it matters anymore but .7 is about .05 higher than the supposed "performance" setting. Messing with the idle screw and IAC settings is a great way for a noob to make his/her car undrivable.

 

Calm down...deep breaths. I won't say another word. In my eyes this topic is closed.

 

In other words you're wrong.

 

Yeap! That's it. I don't want to argue so.......good day

 

Hey Paul howsitgoin ?

Funny this post has been resurrected from the long dead. I drilled out my TPS for adjustment early last summer, then adjusted as per your suggestion and never looked back. The car runs great.

adious,
RP.

 

maybe I should clarify my ghetto rig...let someone depress the pedal while you check the voltage..make sure its the increase in voltage is linear..I dunno if I read it wrong or what I said was misinterpreted but there goes that...Either way IAC and timing should be set before TPS PERIOD..

Daz
13.72@st thomas

 

everytime you change TPS,IAC and timing idle RPM changes..that means you just set your minimum idle on the wrong RPM..Youre not messing anything up if its set right...The timing should be the same as whats in the chip..So that should be set first,the IAC might not be giving the proper amount of air..everytime you touch the idle screw you change IAC/TPS or vice versa

Daz

 

As I remember your car was stalling because of improper TPS setting when we were at St.Thomas...ANd you set it too high too compensate or else would stall(sets a code 14 second runs)..One of the things I did to fix it was readjust minimum air then the TPS..Thats when you got your 13 second runs

Daz

 

I agree....I'm not exactly sure what Acceld is talking about. I think he meant to type boob instead of noob for one. I use a scan tool for most of my settting(Snap on) as for setting the IAC it is pretty simple. If you do it right, even a "boob" can do it. Either way Daz is right..you should always double check IAC and the timing before moving on to the TPS. Sorry if I jumbled up what someone else may have said. Didn't realize this topic was that old...wow. WHat do ya know eh?? I still can't see a GM dealership drilling out the TPS unless someone clarified that the shop would not be responsible. I never siad it wouldn't work, nor did I try to say it was a "ghetto rig" Just didn't want you to screw it up, by accident. Don't really matter though cause it is already done, good job and glad it worked for you.

Keiran

 

Actually, no........It was stalling and not starting because I have 2 injectors that are stuck open when hot. It did run better after you played with it though. You should hear it now

I got my 13 second runs by leaving the car in second and waiting until I was about 200 feet out of the hole before punching it.

Paul
13.70@st thomas with 28ci less than Daz

I want a run next summer you little ****

 

Actually, no............I was referring to PaveTim as a noob because he obviously doesn't have much experience with TPI, no offense.

You don't drill anything vital on the TPS sensor. You simply elongate the slots to allow for more(any) up and down movement. The MAF TPS sensors and SD TPS sensors are mechanically/electronically the same. It's the casing that's different.

And it's not "ghetto rig"........that would be like a chevelle from a Nelly video. It's "ghetto rigged"........like the Daz mobile and my POS.

Kieran, you are a class A *** talker. Congrats

 

Least you could do was spell it right>>.KEIran...LOL

You know what Acceld...I am probably one of the nicest guys you'll ever know, that you wished you didn't. LOL! J/k.\

Seriously I am a nice guy...but the devils advocate!...Sorry

 

Heheh, I should have known that.......one of my best buddies from back in the day was named Keiran. I'm sure you are a nice guy. So am I.

 

I know...we are all nice guys...sorry and girls. Winter blues are starting to get us down...LOL!

 

you mean 12,000 dollars more right?

I forgot my other run was a 13.67..lol..$2500 on a homemade 383 aint bad..Youre TPS voltage was too high which was verified by the code set..guess how it was fixed?reset the IAC..pouring moree $$$ into it huh??ill run you anytime..$5000 on the motor and it runs 13's?gotta be wrong somewhere there..Albeit the TPS..lol..Oh yeah..I have no excuse for having a faster car than you..hehe



Daz

 

Un hunh, and how did that home made 383 turn out? Have all of the peices re-entered the earth's atmosphere yet?

I spent more than $5000, that's for sure but my engine will take alot more than it's getting. My times this year sucked. The whole summer sucked. I have at least 2 injectors that don't close when hot. The noise it makes when I start it is unreal. I spent stupid money on everything and then bought $50 injectors It never had any codes stored. It was cutting out on the highway because my new y-pipe was hitting the road. When that happened it would flash the red light of death but it wouldn't store any codes. Don't tell me all that messing with the IAC did anything other than give me a 1200rpm idle. We never even found a proper driver to turn the idle screw.

I'll see you and that big block at the track next year. That's if you can keep it together or avoid having that rolling violation impounded.

 

Daz, I swear to ***, you're the only one that's any fun on this board anymore.

Thanks,
Paul

 

Ahhh! Now I'm jealous...I thought you liked me Acceld! LOL!

 

ahh back to the kABOOM..Its theFluidamper not going with the Scat crank..sorry if I said $5000 I meant $8K(ouch)..And where did you get the big block idea?..hmm more **** talk from a guy who spent $$ to build on Edelbrock heads..hahahaha..My guess is you need another $2K to get to 106mph..I guess the Lingenfelter book really sells..

Daz

 

hard to be friends to a guy who spent less and have faster timeslip(s)and tries to help when the high dollar emission legal(or is it?)cant break 14's...damn it I hate winter..lolol..just come down here winter and well do a stripgathering or something..All this car work/mods I have in line is driving me nuts

Daz

 

Yeah, my heads are **** I've run well over 106mph. My engine was not healthy in the last parts of the summer. Where are you getting your $ figures? You put a fluidampr on a crank that they specifically told you not to use one on? That looks good on you. I expect that the lingenfelter book does sell well, what the **** does that have to do with anything? Oh wait, he must be wrong because his parts and engines cost a little more than others.

Daz, you're ignorant. That may be why you're so much fun. Keep playing your stupid little "mystery engine" games.

Now you go.

 

Yeap winter blues have set in...Ain't it obvious????

 

My 2.4 and 2.3 60 footers may have been hindering performance..........but i'm not sure. What was your excuse for the **** times? I can come up with alot more for myself.

 

Do you want some more ?????

 

Eye of the tiger man...bring it on!! LOL!!

I've worked with smart mouthed mechanics for over 15 years. I can keep up with the best of them.....

Speaking of which... Did you ever hear this one?? Bear with the spelling...

What do you call a menanite, on the side of the road with his arm half way up a horses arss????????


A mechanic!! LOL!!! HA HA HA. Hope you laughed at least????

 

Holy Krap.... don't make me moderate this one

Can I get in on the ET vs investment game?

$2,000 including car -> 13.9

(that figure does not include the 4th gen seats because I sold them to IROCKER)

PS: I'm going to run 12's this summer for another 1K

 

Jay, I have already hijacked the **** out of this thread. It doesn't need to be hijacked in another direction.

In other words, your $2000 13.9 second car makes me angry. Very angry.

I'm gonna sell averything and give up. I need a Honda or maybe a Hyundai. Kia is making wonderful product now a days. How much is a new Sorrento?

 

Lock us out???Oh plz don't. Money vs Et's..Ouch... I suck then..I have over $10,000 approx. in my car now, car itself is worth about $3000 of that... to many new GM parts add up. And I only ran a best of 16.01 @ 87 mph this year. 1 run and put a hole in my rad. The one wheel peel got me a wopping 2.4 60' due to spinning from 1st to 2nd badly...Posi will be in next summer and my vacum leak will be fixed. I'll try to keep up with you 13 second folk.. Or maybe beat that???who knows?? LOL!!!! Night all!!! It's been fun!


Mine's on the left.


Keiran

 

Lol... if I had picked up a 3k stall and a decent intake I know it would go 13.5 as is.

As for you're car.... GET SOME DECENT TIRES! you could easily knock 8 tenths or more off you're ET just by planting a 2.0 60'

 

Kaz, I would have burned that.........but then i'm a very small man.

 

Dude, I hate to tell you.... but even if you account for the bad 60'er your MPH is weak like 305 styles. There is something wrong with you're car.

 

Yeah I know..Car was running like crap..Turned out to be a intake leak on one of the runners. Fixed it and will be back next year. Much faster I hope LOL! G night!

 

I dont make excuses..I raced it as is end of story
As for my reasons you seem to ask them all the time..hmm wonder why?bottom line you lose..lol.."BTW nect time learn how to adjust the TPS yourself..,,lol Dont even know if your idle screw takes a torx,a robertson or a flat screwdriver ahahahhaa..I wont ask for a REASON on that one..lol

Daz

 

Sometimes failure is the only way to get better. As for the time slip...that was the first run since she actually first started. No prior runs , no prior setup. 16.1 isn't all that bad since I had no set up time to play with... Next year...next year. I don't embarass easily. Lets roll!!!! AH SH*t it's snowing...OK next year...LOL!

 

Ya ha ha!! I am menonite!