Throttle Position Sensor Enhancer?

Snake oil- The TPS tells the cars computer what position the throttle is at so the car can adjust the Injector pulse appropriately. It generally reads a

1-5 volt reference signal-- 5 being wot. Increasing the voltage in or out of it will set a Code; and possibly burn out the computer. Don't mess with it.

I had read on a grand prix forum that (on newer GTP's, I can't speak for the older generation like mine) the maximum voltage that the TPS will put out is 3.2 to 3.4 volts, and that the WOT should actually be at 4V to use the full engine potential. Are they wrong in saying this? It seemed plausible but I had my doubts too. Anybody else have any opinions? If the consensus is that these are a waste of time, are there any other inexpensive mods worth looking into?

Thanks.

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I'd have to get into the manual to verify the exact numbers for the tps, but it takes the cpu 5v voltage and converts it into a percentage for the CPU to do its calculations; changing the upper end voltage wouldn't do much unless the car could only read a percentage of 85% due to the original TPS being bad. I can see no real effect for a performance TPS. I'll check the books at work tomorrow.

Measure your TPS at full throttle. Check to make sure the throttle blade(s) are wide open. If they aren't and you're not at 5V, you might be able to grind the throttle stop for a bit more power at full throttle.

Ray

I'm basically at the idea that it's not a good idea and is generally a waste of money. Can anyone suggest anything else for a performance mod that is fairly cheap and doesn't require much or any physical modifications to the car? I'm a little strapped for cash and just a beginner in the mod game, but I'd love to learn. Thanks in advance.

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It's good you gave up on the tps thing for your 95 GP. Voltage above 4.8 would set a problem code and likely burn out the ecu.

IMO, the best thing you can do is save up about $500 and then take it to a "tuner". Have them install and program a new chip. Keep the old one to put back in for yearly safety / smog inspections.

Forget the cold air intake - you won't notice any difference unless you race at wot. Keep the throttle body clean instead.

Nitrous.

Before you blow me off... hear me out.

I have a 2001 Trans Am. On it's first outing at the drag strip it ran a

13.8@102mph. By driving better, I got down to a 13.4@104mph. A set of drag radials knocked it down to a 13.23. An intake lid was a tenth down to 13.12 and a 100 shot of Nitrous has given me a 12.185@111.8mph. I've never had the valve covers off and the car has no other performance mods.

I had to make two small holes in the trunk area for the bottle hold down bracket and I used an aftermarket intake lid because you have to make two holes in it (and it's worth a solid tenth.) Otherwise I could return the car back to stock in about two hours.

Cost... under $1000 US.

the downside: My stock clutch barely made 30,000 miles. When the bottle runs dry, the fun is over. Also, I can't use the nitrous on the street, because it'll break the tires loose at any legal speed when it starts spraying. ;)

Name me another mod for $1000 that'll knock a full second off your times. If your car is supercharged, I'd look into pulleys for more boost.

But be warned... more power = more breakage.

Ray

I don't think I want to put NOS in my car, it's getting up there in age and mileage. Anyway, I definitely need something though. It's supposed to have 210HP but right now I have a hard time even breaking the tires loose. I don't really have any mods yet other than removing the MAF screen (don't want to get int a debate about that though), and the only real maintenance I have done is a change of all fluids and all of the filters (including fuel) as well as the plugs, and new mufflers are coming. What should be the next step to get it back to at least its original glory? I've used some 'Restore' engine restorer to try to regain some compression and I have some BG 44K on the way to clean the fuel system in case I have badly clogged injectors. Anyone know what would be the next most common cause(s) of lost power and how to fix? I absolutely love the car but I'm almost embarrased that it can barely hold its own against a Cobalt LS that's supposed to have 65HP less.

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Also, I should say that it has been checked and is not putting out any error codes.

One more thing, does anyone know how much horsepower and torque could be gained by having dual Magnaflow mufflers installed vs. OEM-like replacements?

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