Faulty TPS??
Thread Starter
Supreme Member

Joined: May 2002
Posts: 1,333
Likes: 1
From: Texas
Car: 1991 Z28 Convertible
Engine: 350 TPI
Transmission: 700R4
Axle/Gears: 3.23 with Eaton posi
Faulty TPS??
Jeez...one thing after another since having the engine replaced. If you are knew to my woes here's the story:
Put in a 350 in place of the 305. My timing was too far advanced, I had a broken ignition rotor, my afpr was set at like 60psi. This was all when I got the car back. I found all these things after trouble shooting hesitation under load, some rough starts, and dying when coming to a stop [infrequently].
I set the timing to 6, replaced the rotor, and dialed back the fuel pressure to 44 psi.
Checked my TPS sensor (speed density) and found it to be a at .610v. I adjusted that to .710v. I checked it at WOT and it would read as high as 1.xxx. Isnt it supposed to increase to 4v under WOT? I was doing this with the car in park and turning the throttle lever at the TB.
Put in a 350 in place of the 305. My timing was too far advanced, I had a broken ignition rotor, my afpr was set at like 60psi. This was all when I got the car back. I found all these things after trouble shooting hesitation under load, some rough starts, and dying when coming to a stop [infrequently].
I set the timing to 6, replaced the rotor, and dialed back the fuel pressure to 44 psi.
Checked my TPS sensor (speed density) and found it to be a at .610v. I adjusted that to .710v. I checked it at WOT and it would read as high as 1.xxx. Isnt it supposed to increase to 4v under WOT? I was doing this with the car in park and turning the throttle lever at the TB.
Senior Member
Joined: Sep 2005
Posts: 709
Likes: 0
From: Middleboro, MA
Car: 1988 Pontiac trans am/gta
Engine: 350
Transmission: 700r4
Axle/Gears: 3.23's
Isnt it supposed to be set for .54 No throttle?
Should be near 4.5 volts WOT and if u see any 0.00 in between closed throttle and wot its time for a new one
Should be near 4.5 volts WOT and if u see any 0.00 in between closed throttle and wot its time for a new one
Thread Starter
Supreme Member

Joined: May 2002
Posts: 1,333
Likes: 1
From: Texas
Car: 1991 Z28 Convertible
Engine: 350 TPI
Transmission: 700R4
Axle/Gears: 3.23 with Eaton posi
.54 for maf and .71 for SD right?
I'll recheck it again. I couldnt get it past 1v on wot. I'll check for any 0.00 reading
I'll recheck it again. I couldnt get it past 1v on wot. I'll check for any 0.00 reading
Thread Starter
Supreme Member

Joined: May 2002
Posts: 1,333
Likes: 1
From: Texas
Car: 1991 Z28 Convertible
Engine: 350 TPI
Transmission: 700R4
Axle/Gears: 3.23 with Eaton posi
This is where I got mine from.
Tech Articles - Adjusting Your TPS
I dont know.
Either way, can you monitor the voltage while in park and revving via the throttle at the TB?
And do you really need to adjust IAC on an other wise stock engine?
Tech Articles - Adjusting Your TPS
I dont know.
Either way, can you monitor the voltage while in park and revving via the throttle at the TB?
And do you really need to adjust IAC on an other wise stock engine?
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