Do I take a voltage reading on it? If so, what should it read? Can I do any adjustments on it? Thanks.

 

ttt for ya. curious as well.

 

With the TPS, I am normally looking for an intermittent signal from the worn TPS.
So, I use a scan-tool (Tech-1A/AutoXray) that takes a "snapshot" of sevral frames of data while I am smoothly moving the pedal from minimum to maximum throttle -- this can be done with the key on and without the engine running.
Then, I graph the frames of data to see how smooth the graph is responding.

Tom Piper

 

Thanks. I need to get the equipment to scan and tune my car. It's a 96. I'm thinking tunercat, but can't decide between converting to obd1 and having cheaper (supposedly) equipment + no after-cat 0s sensors, or leaving it obd2 and getting the tunercat package that is supposed to include all the cables I need. But, that's another thread. I'll do a little research and post my question when I have a little more info.

 

Easy. With the key on, engine off, use a voltmeter and probe the blue wire. Should be around .7 volts. It should increase with throttle position to about 5 volts.

 

Thanks. I can do that tomorrow. I'll post my results and we'll see if that has anything to do with my low rpm stumble. It's most obvious if I'm going 45mph in cruise control. If I could find my vacuum gauge, that would be a world of help.

 

I got to test it today. .4 volts closed, 4.4 volts fully open. I was moving the throttle by hand at the throttle body, so I can't be sure how smoothly the voltage climbed.
What do you think?

 

That doesn't sound like bad voltage readings. Closed throttle voltage will be around .5 to .8 volts. Full throttle voltage will be approx. 4.5 to 5 volts. Specs in my Haynes say 4.5 or greater = full throttle. So yours is pretty close to spec.

I had a slight stumble at light load/low throttle a while back that progressively got to be a bad stumble under the same conditions. Drove me nuts trying to find it. Checked some of the same things you are. Turned out to be bad connection in the ignition wiring harness. I was using an Accel 300+ ignition box and thought that might be at fault. Unplugged it and reconnected ignition in OEM configuration. Problem went away. Just for fun I plugged the box back in and problem was still gone. Just a bad connection I guess. You might check that. Good luck.

 

Sounds like a good thing to check. I'm new to LT1s, though. Can you tell me exactly where it is? The only time I get to look at it is after dark, so I can't really just poke around looking for it. A guy could die of old age before he found it that way.

 

Ok, trying to do this from memory. Since I had the Accel box I had some extra harness connections that you won't have. But I think you'll want to check the coil pack wiring harness connection ( I didn't catch what year you have. So if it's a 96-97 you'll have only one. If it's a 93-95 you'll have two connnectors.) I'd also check the connector going to the ignition module. You'll find all of this bolted to the front of the engine on the right cylinder head as you are facing it. Hope this helps a little.

 

Sure it helps. Are you kidding? If I can get back to the work center tomorrow during lunch when it's light I'll check those.

 

Well, I finally got to check all of my connections and nothing helped. I did manage to get the hard start problem I've been having fixed. While we went out of town, I gave the car to my mechanic to have some things done, and I mentioned my starting problem. It turned out to be the coolant temperature sensor. It was reading extremely cold and feeding the engine way too much fuel. Now if I could just get everthing else fixed so easily. Soon I will get to replace my shocks. I can't wait to ride in it after I do that.