P-0068

hound9164 · Post by **hound9164** » Fri Mar 02, 2007 11:40 pm

P0068-MANIFOLD PRESSURE/THROTTLE POSITION CORRELATION

does anybody know how to fix this? i looked over the older posts on it, but they are from 2004, and i was wondering if a real fix was ever discovered.

how can i reset my computer just to get the damned light off lol?

could the fact that i needed to go out and get new vacuum line, as opposed to the little stub of hose mpx gave me? larger hose needed?

i am kinda lost on all this, and i dont know why the CEL came on today, when i installed the TB last week lol.

kc2005ptgt · Post by **kc2005ptgt** » Sat Mar 03, 2007 12:41 am

well, you can reset the ecu by unplugging the battery and removing the fuel pump relay from under the hood for about an hour... it will go away then, but with this code, it will come back.

Post by **Diablo0** » Sat Mar 03, 2007 2:24 am

Looking at the Diagnostic manual here is a short exert from it on the possible cause of the code...

P0068-MANIFOLD PRESSURE/THROTTLE POSITION CORRELATION
When Monitored: With the engine running and no MAP Sensor or TP Sensor DTC’s set.
Set Condition: The PCM determines a valid range in which the TP Sensor should be, at
a given RPM/Load. The actual TP Sensor voltage is then compared to this value. If the TP
Sensor voltage does not fall within the expected range within a predetermined time an
error will be detected. Two Trip Fault.

POSSIBLE CAUSES
GOOD TRIP EQUAL TO ZERO
HIGH RESISTANCE IN MAP (K7) 5 VOLT SUPPLY CIRCUIT
RESISTANCE TO GROUND IN MAP (K7) 5 VOLT SUPPLY CIRCUIT
MAP SENSOR
HIGH RESISTANCE IN (K1) MAP SIGNAL CIRCUIT
RESISTANCE TO GROUND IN (K1) MAP SIGNAL CIRCUIT
HIGH RESISTANCE IN (K4) MAP GROUND CIRCUIT
PCM
TP SENSOR OPERATION
HIGH RESISTANCE IN TP SENSOR (K6) 5 VOLT SUPPLY CIRCUIT
RESISTANCE TO GROUND IN TP SENSOR (K6) 5 VOLT SUPPLY CIRCUIT
TP SENSOR
HIGH RESISTANCE IN (K22) TP SIGNAL CIRCUIT
RESISTANCE TO GROUND IN (K22) TP SENSOR SIGNAL CIRCUIT
HIGH RESISTANCE IN TP (K167) SENSOR GROUND CIRCUIT
PCM

hound9164 · Post by **hound9164** » Sat Mar 03, 2007 12:43 pm

so far i have seen a few other posts on this. i know the r/t guys have this problem, but some 03 and 04 neons do as well.

as far as i understand it, i should just reset the computer, and hope i dont throw the cel again. supposedly, it dosnt happen until a certain RPM, so if i can figure that out, i can avoid that rpm.

MoxHair · Post by **MoxHair** » Sat Mar 03, 2007 6:52 pm

0068.. DUN DUN DUN

It's a horror story code.

It will come back.

There is no cure. So dig a hole and stick that TB 6 feet under.

I've personally have dealt with this code. Nothing worked, Not a ECU reflash, not a Map Clamp, Not new Vacuum Hoses, nothing.. I tried everything.

Good Luck