tps?
wrightz28
10-11-2005, 03:10 PM
alright, I'm flat on my face on this one.
victim is my 85 305 tpi.
problem is out of nowhere, driving along the engine began sputtering and the harder you pressed on the gas the more it fell on it's face.
immediately I thought it was a fuel problem. changed the filter and pressure tested and everything seemed to be in order. nope, as soon as put into gear same crap.
check the entire ignition system out, not the prettiest but I have seen worst, so average mid life on it. and spark is nice and blue, plugs and wires are not but 3 moths old, and none of the wires are burned either.
But the motor will start and then fall dead in a matter of seconds.
so i try the maf out as they are prone for this behavior. the first times, yes it would start, run like crap then eventually die. and run rich.
now if I disconnect the maf and tps it will idle all day long and not burn your eyes out of their sockets.
after this discovery, I found that there is a flat spot in the tps at about 3.3 volts in sweep.
dosen't throw any codes, and i would think the darn thing should still idle since the flat spot is at what 2/3 throttle, no?
if any body out there has had a similar issue with a tps behaving like this please say so, I've never seen this. I've always seen with a flat spot, the car will ilde unless the spot is at the low voltage, closed butterfly end. $59 is a bit of gamble right now, Car is getting tucked away for winter but i'm stumped here
victim is my 85 305 tpi.
problem is out of nowhere, driving along the engine began sputtering and the harder you pressed on the gas the more it fell on it's face.
immediately I thought it was a fuel problem. changed the filter and pressure tested and everything seemed to be in order. nope, as soon as put into gear same crap.
check the entire ignition system out, not the prettiest but I have seen worst, so average mid life on it. and spark is nice and blue, plugs and wires are not but 3 moths old, and none of the wires are burned either.
But the motor will start and then fall dead in a matter of seconds.
so i try the maf out as they are prone for this behavior. the first times, yes it would start, run like crap then eventually die. and run rich.
now if I disconnect the maf and tps it will idle all day long and not burn your eyes out of their sockets.
after this discovery, I found that there is a flat spot in the tps at about 3.3 volts in sweep.
dosen't throw any codes, and i would think the darn thing should still idle since the flat spot is at what 2/3 throttle, no?
if any body out there has had a similar issue with a tps behaving like this please say so, I've never seen this. I've always seen with a flat spot, the car will ilde unless the spot is at the low voltage, closed butterfly end. $59 is a bit of gamble right now, Car is getting tucked away for winter but i'm stumped here
FormulaLT1
10-11-2005, 05:36 PM
You know the TPS is adjustable , right?
wrightz28
10-12-2005, 10:05 AM
Yes, and it is set at .54 volts closed and sweeps to 4.5v at WOT as should be.
Min. idle speed is correct as well as IAC function.
Min. idle speed is correct as well as IAC function.
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