1G TPS Adjustment Question

[dspecv]

I just ran the datalogger, and the TPS reading was at 7.84 during idle. I've read that this should show at 10% during idle, and was wondering how I go about adjusting this? I've searched previously and was unable to find anything about adjustments on the TPS, or would I just need to buy a new one?

 

[steve]

What car do you have (Please update profile). The spec is different between 1G and 2Gs.
In both cases you loosen the two bolts holding the TPS and rotate it.
On a 1G you rotate it until you read 0.5v or 10% output.
On a 2G you have to adjust it by where the internal IPS switches while using a feeler gauge between the pully and stop screw.

Steve

 

[dspecv]

Sorry about that, I was having trouble with my computer logging me out when I was updating my profile earlier. I have a 91 GSX, so am I going to need to remove the throttle body when I adjust this, or can I do it while the car is running.

 

[steve]

I have a 91 GSX, so am I going to need to remove the throttle body when I adjust this, or can I do it while the car is running.

The car doesn't need to be running but getting at the two bolts so you can loosen them and turn the TPS can be a PITA without removing the TB or the fuel rail. Once they are loose you can just rotate the TP until the logger reads 10%.

Steve

 

[alex99gst]

The car doesn't need to be running but getting at the two bolts so you can loosen them and turn the TPS can be a PITA without removing the TB or the fuel rail. Once they are loose you can just rotate the TP until the logger reads 10%.

Steve

I tried tonight to get it off since I just got a code 14 reading and after trying for a good hour and losing 3 sockets and a philips head thing I got so mad I smashed the tube light thing I was using to get some light on the valve cover and now I have an engine bay full of glass shards. Way to go Alex.

 

[dspecv]

, I can't wait to start on this thing then.....

 

[joosdawg]

I tried tonight to get it off since I just got a code 14 reading and after trying for a good hour and losing 3 sockets and a philips head thing I got so mad I smashed the tube light thing I was using to get some light on the valve cover and now I have an engine bay full of glass shards. Way to go Alex.

dang dude your nuts! dont hurt your car on account of yourself trust me.

 

[steve]

, I can't wait to start on this thing then.....

It's a whole lot easier if you remove the fuel rail but you need to make sure that you have new o-rings for the fittings and injector insulators for the head before you start and then discover you need then to put it back together. Or at least I find pulling the fuel rail easier than pulling the throttle body replacing those gaskets.

When your done adjusting the TPS don't overtighten the lower bolt. I just leave it tight enough that it resists me turning the TPS with the top one loose and then tighten the top one that is easy to reach.

Steve

 

[alex99gst]

It's a whole lot easier if you remove the fuel rail but you need to make sure that you have new o-rings for the fittings and injector insulators for the head before you start and then discover you need then to put it back together. Or at least I find pulling the fuel rail easier than pulling the throttle body replacing those gaskets.

When your done adjusting the TPS don't overtighten the lower bolt. I just leave it tight enough that it resists me turning the TPS with the top one loose and then tighten the top one that is easy to reach.

Steve

So removing something is necessary I assume? Either the fuel rail or the throttle body?

 

[AgntorangeDSM]

i just found it easier to remove the TB when i did this about a month ago.

 

[steve]

So removing something is necessary I assume? Either the fuel rail or the throttle body?

I have yet to find a way to unscrew the lower bolt holding the TPS in place without removing one or the other, so that seems like a fair assumption.

Steve

 

[joosdawg]

i actually just did this today and found a way! its not easy and it takes just as long as trying to take off the rail or TB.

I used a stubby 8mm wrench and got it to turn very very slowly at a time but worked. Had to take the line from the PCV off and the injector harness but then i had enough room, barely. I would just suggest taking something off too because I don't even know if I had the correct torque tightening the bottom bolt :/.