Throttle Position Sensor Problem?????

[JJAB]

Gentlemen, I have a 2001, cable driven 5.3 pushed by a 700r4. Here is my problem. At idle, the motor would surge up and down. Driving it, if i turned left or right, or tried to go faster than 40mph, the motor would cut out. Initially, I thought i had a fuel pressure problem or a vacuum leak at the intake. Both the fuel pressure doubt and intake gasket leak doubt has definatley been addressed and "fixed". Today, when I crank it up, the motor wil idle up and down and or when I accelerate the motor in park, it pops at low rpm as if it is starving for fuel - THIS IS WITH THE TPS PLUGGED UP!! If I unplug the TPS, the motor revs awesome. But when I come off of the gas it will die if the TPS is not plugged. HELP HELP!

Also, this is with a new TPS sensor and the only code I am getting is P0650, which the check engine light code.

[Clyde65]

PM Clienbarger, he is in Ft WOrth and can help if you cant get an answer quickly.

[clinebarger]

John, My username is clinebarger....Had to rib you a little.

JJAB, Unplugging the TPS sould set a TPS code, Does it?
How are you retrieving codes? Do you have a scan tool?
You checked the grounds on the back of the engine?

[JJAB]

I am using obII scan tool. Yes, I have double and triple checked the grounds. I put a call in to a tuner and the advice was to ohm the tps wires to see if the ohm are dropping. Thing is, there are three wires going to the TPS plug, im assuming one is a ground, And I do not know what the ohm should be on each wire. Also, when I find out what each wire's ohm should be, do I properly connect the TPS plug, accelerate the engine and check if the ohm are dropping. Please help me out. THANKS!!

[clinebarger]

There is a easier way,
The TP voltage should read about .50 to .78 volts at closed throttle & increase to near 5 volts a full throttle.

If the scanner is reading 0 volts....Do this test.
Unplug the TPS...Jump the 5 volt reference (Grey) wire to the Signal (Blue) wire with a paper clip, The scanner TP voltage should read 5 volts.

If it does, Ohm the black wire to a ground, The meter should read around 0 ohms if the ground is good.

[68GMCCustom]

Ooooh oooooh....clinebarger.......

Do you have one of these for an LS series MAP sensor? if so...thanks in advance, if not thanks for replying.

[clinebarger]

Originally Posted by 68GMCCustom

Ooooh oooooh....clinebarger.......

Do you have one of these for an LS series MAP sensor? if so...thanks in advance, if not thanks for replying.

Here you go.

[68GMCCustom]

Cool! Thank you sir!

[JJAB]

Clinebarger, I have not done the test you told me to do yet, but let me ask you; with the TPS plugged, it seems as if the car only allows you to accelerate the motor up to around 1000 to 1500 RPM, then when you come off of it, it begins to surge up and down. No codes are present until the TPS is unplugged.

The customer was so excited about driving the car, he hasn't brought it back to me to perform the test.

[clinebarger]

The most common proplem with doing ANY fuel injected swap is clogged fuel injectors, So if the engine sat around for awhile before the install You might want to clean the fuel injectors.