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hello thank you for help my email adress is tracycmodesto@hotmail.com and ill get right on checking these probleams
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hello i have a 1999 pontiac grand prix and after replaceing a fuel pump in this car the s.e.s. light came on i went to auto zone and pulled codes and po 452 came on the book i have says that means Fuel Tank Pressure Signal low voltage im lost what does that mean? please any help you can give im very very thankful
Answer -
OK, WHY did you replace the fuel pump ?.
There is what is called a FUEL TANK PRESSURE SENSOR that mointors the amount of VACUUM that is normally found in the gas tank. This vacuum is RELEASED whenecer the fuel system is opened up.
Make SURE that your electrical connections are connected properly and make SURE the gas cap is on TIGHT. Drive the vehicle for 2 or 3 hours and your SES light will probably go out once the normal vacuum returns to the fuel system and is SENSED by the FUEL TANK PRESSURE SENSOR.
This can also happen if you forget to put the gas cap on tight.
Just make SURE everything is connected TIGHT and drive the vehicle for a fwe hours and the SES will go out.
autohelp hi i had to replace the fuel pump because the other one went out that was three months ago they light has been on for three months now i have cleared the codes and after four starts it comes back on i also had to add a new fuel cap and it cleared a code so the fuel cap is not causeing this light to stay on
Answer -
We could have SAVED some time if you had stated this information the first time. That is why I ask in my bio that you provide ALL past history repairs.
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FTP = FUEL TANK PRESSURE SENSOR.
PCM = POWER CONTROL MODULE.
Being absolutely POSITIVE that you do NOT have ANY problems with the fuel gage reading being erratic at any time. If it is erratic or is intermittently erratic the fuel sending unit in the fuel tank will have to be replaced as it is causing erratic voltage signals to the FTP unit.
OK, Then your SURE that you did NOT miss an electrical connections or maybe accidently BENT a pin connector within the plug in connection pack(s)at the fuel tank connector for the fuel pump/meter and the connector for the FUEL TANK PRESSURE SENSOR (FTP).
If ALL the electrical connectiona are OK and you have no erratic fuel gage readings then you have 3 possibilities:
1. the FTP is faulty.
2. The PCM is faulty.
OK, The FTP connector end has 3 wires in the connectors colored:
A = black/white.
B = Dark Green.
C = Gray.
Terminal A of the DISCONNECTED FTP plug in the connector end of the main wiring harness, NOT at the fuel tank connector end. There should be 5 volts with the ignition ON, Engine OFF, IS THERE ?. If you have 5 volts you most likely have a faulty FTP sensor.
If you do NOT have 5 volts, Locate the PCM electrical plug at connector C1 circuit # 46 (gray wire) and check for 5 volts. If you have 5 volts at the PCM and NOT at the FTP end where we tested at above, You have an OPEN circuit of the gray wire from the PCM to the FTP connector.
If you do NOT have 5 volts at the PCM, The PCM is faulty or you have a DEAD SHORT of the gray wire from the PCM to the FTP of which MUST be corrected BEFORE you replace the PCM or you WILL DESTROY the NEW PCM.
Without the proper SCAN TOOL this is the ONLY option of testing the circuit.
If you can read an electrical schematic, I can scan and e-mail you a schematic for you to look at.
Your problem is either:
1. Faulty or shorted to ground wire connections.
2. No 5 volt reference signal from the PCM.
3. An erratic fuel gage reading. Requires new fuel meter in
fuel tank.
let me know your e-mail address as pictures are NOT allowed on this web site.
autohelp
AnswerIF after your tests your problem is still unresolved, Contact me at:
meperganfortis@msn.com
and include your vehicles:
YEAR:
MAKE:
MODEL:
ENGINE SIZE:
CURRENT PROBLEM:
As I get 30 to 60 questions DAILY and can't remember a question asked 2 days ago on this board.
autohelp
