Jump to content

TPS question ... Of a different sort.


Recommended Posts

So, I picked up a 92 XJ and in the back just so happens to be two 2.8L GM V6 boat anchors (extra scrap weight value I guess).

So I start looking at what I can scavenge from them, alternator, throttle bodies for future projects ... Wait a minute ... That GM tps looks awfully familiar ...

Unfortunately my stock TPS died (old AMC manual version) and got hacked during the HO head/TB conversion. But the GM tps' on the 2.8's looks and feels just like the old AMC/Renix tps... Even the same arm actuators. The plug orientation is different, but if it fits and works the same.... They are only $28 on rockauto... 1988 Camano 2.8L tps is what I have two of.

Am I loosing my marbles or is it just possible I can bolt these on?

Link to comment
Share on other sites

Tried it, got an idle of 2500rpm, and if I relaxed the sensor, a no start. So much for the cheap and easy ... It was too good to be true. Unless the junkyard throwaway sensors were junk, since my stock sensor did the same thing when it went out. But I doubt it.

Link to comment
Share on other sites

I think I found it,

 

GM sensor -

A - ground

B - SIGNAL

C - 5V reference

 

Renix -

 

A - Positive 5V reference

B - ground

C - SIGNAL

 

SO... Assuming I have this right, I just need to re-arrange the wires in the connector and the cheaper GM sensor ... That is roughly $100 cheaper ... And readily available ... Is a doable thing.

 

Makes sense why my idle went off the charts now.

 

Gonna try this when I get the chance.

 

In other news I got my ebrake working again, made me feel better after round 1 cheap tps fail.

Link to comment
Share on other sites

Hope it works out. In the pits at FSAE Lincoln last year we though we had some issues with our TPS, and we couldn't find our spare. We went to the pit next door, and their spare bolted up and plugged right in. Slight recalibration (we always recalibrate for new sensors) but it worked great, even though ours was off a '90's GM truck and theirs was for a 2000's Suzuki. Like I said, TPS's are pretty similar in form and function.

Link to comment
Share on other sites

Yeah, the issue is the way the Renix reads voltage, and the way it is wired internally it seems. It may read voltage (climbing) the same as the GM sensor, but the internal pinout of the sensor is different making them a direct swap incompatible.

And Suzuki and GM have had a long relationship over the years, I would suspect a considerable compatibility there.

From my research a simple wire swap should allow use of the 86-91 2.8L TPS (86-87 are physically the same as the Renix, 88-91 point the connector straight up but function the same).

I'm making and quickly adapter harness right now.

 

If it works, and 87 s10 tps is a direct swap with a simple wire rearrange on the plug.

And they run $21-32 on rockauto, vs $118 for the Renix manual version and $60 for the auto.

Link to comment
Share on other sites

So ... The crossover harness ...

 

 

WORKS PERFECTLY!

 

SO ...

 

The GM 2.8L TPS (and pretty near all GM engines) from 86-91 (and possibly later as GM TPS still work the same) will work to replace the 5spd renix sensor.

 

Use the 86-87 S10 version for a correctly angle plug, 88-91 will have the plug straight up.

You will only need to rearrange the wires in the plug once and it's a direct swap.

 

Picture of my hacktastic adapter harness in a minute. Just have to let the phone charge.

But I did drive around the block and back again.

Link to comment
Share on other sites

I have the tools, I made the harness as a tester, I didn't want to rearrange the connector before I proved function. Hell, I didn't even adjust the TPS or even add the second spacer, it's just quickly popped in place. Idle is better than my current Renix TPS.

 

Now that I have proven it works, I'll rearrange the wire order in the stock connector and on the Renix side of the adapter harness . And the harness will now become a test/adjuster harness.

I didn't want to futzing with it too much if it wasn't going to work.

Link to comment
Share on other sites

The two TPS' side by each.

 

The conversion harness to test it all.

 

Stock wires re-arranged in the plug to GM pattern.

 

The old adapter harness reset for use as a test dongle. The wire nuts simply cover the wire leads used to test and adjust.

Link to comment
Share on other sites

Because it's on an HO throttle body.

I did an HO head (92) and manifold (99 intake) back in October-ish.

Been driving around for the last day, the GM TPS even got rid of a hesitation when starting in first, always thought it was another unrelated issue.

Link to comment
Share on other sites

The TPS for an auto trans is plug n pray for a manual trans. Just has an additional plug. I work at a Carquest auto parts, and the computer did not even show a listing for a manual trans. Auto trans TPS prices that I have seen have always been significantly cheaper. 

Link to comment
Share on other sites

yes, but the GM TPS is cheaper still  ... and a bazillion times more likely to be found in a Wrecking Yard (how many 2.8L manual trans cars/trucks left the GM factories between 1986 and 1991? Compared to 4.0L Comanche/Cherokee's from 87-90?).

 

Last check the Auto trans sensor was ~$60 on rockauto, the GM sensor is $21 on rockauto. Only takes a quick wire swap to work, and is completely reversable.

 

If I had an auto .... wouldn't have even crossed my mind, but I just happened to have a manual, and happened to get saddled with these two 2.8L efi engines in the back of my parts XJ so .... now there is a source for 5spd manual TPS's compatible with the Renix system.

 

FYI - the sensor next to the GM takeoff is an auto TPS that used to reside on my engine until I tried the GM sensor (AMC on the left, GM on the right). it had a flat spot on take off, and when I got it the wiring wasn'f sealed properly (hence the RTV) ... since I had these two sensors, and the inkling to try ... I have now put just over 500kms on it without even a hiccup, flat spot, hesitation or burp.

I just wanted to share my findings was all, and add another JY source for parts (the original Delphi sensor is still going to be the more reliable one).

Link to comment
Share on other sites

  • 2 weeks later...

Just an update, another 1000km's with zero issues and a better idle. Going to start looking for these when I JY crawl now.

Just to clarify, the only modification needed is to re-arrange the wires in the stock plug. Simple as that. I still have my renix TB I can mount one to and snap a pick if anyone is remotely curious.

Link to comment
Share on other sites

  • 1 year later...

So, Just a long term update. This GM TPS has been working for the last 1.5yrs now. Recently picked up a spare for $25. So pretty much cheap and easy.

Going to start looking at compatibility for 2.5L (pre 92 so renix TBI) next. Looks like I should be able. To utilize the same GM TH32 with a simple wire swap again.

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share

×
×
  • Create New...