carthelosz28

I'm an excited new member to the LS community! But I've got one issue...
Please help me out.
I've tried disconnecting the battery, pulling fuses, scanned over and over again and I still can't figure it out. I've read over what feels like a million posts.

My SES light came on about a year ago, never been an issue until now since it needs to get smogged. Initially I had a code for each of the 4 o2 sensors and the fuel tank pressure sensor. Since then, I have replaced all 4 sensors and the fuel tank pressure sensor. The codes have been gone for months and I have been checking every so often and still no codes ever show up. The SES light stays on. It goes off if I disconnect the battery only. But then it comes up before I even leave my neighborhood. I'm desperate for help.

Thanks in advance. Anything is appreciated.

SouthernRex

Which codes exactly?

98CayenneT/A

A cracked or loose gas tank cap is a good possibility.
I'm assuming this is in a f-body body?

If you know anyone with another gas cap, swap with them or try there's.

carthelosz28

The codes that are gone now were;
p0452, p0131, p0137, p0151, p0157, and p1133

carthelosz28

I can try that! Maybe I could just try junk yard gas cap? Been meanin to go lately lol...plus someone stole my antenna:

G8One2

Circuit low faults are generally due to excessive resistance in that circuit. Could be a pinched wire or one that's not fully seated into whatever it plugs into. Could be corrosion on the pins. Seems to me since they are all O2 related, you should be checking each circuit. Insufficient switching usually caused by the sensors not getting hot enough to do so and could be a secondary cause from the first issue.

carthelosz28

Theres probably threads on this...but what should I do? Do you mean like take a multimeter to each of the sensors wiring? Or should i just take it to the shop/dealer?

G8One2

Well that depends on your skill level. If you have little to no experience with a multimeter and checking circuits, you should take it in. Otherwise you could potentially cause more issues poking around at it.

98CayenneT/A

With him not throwing any codes anymore I would not think it's the o2's.

He did have a fuel tank pressure sensor code and with the ses light coming on but no codes are coming up I absolutely would start with a new gas cap.

Run to your local parts store and grab one.

G8One2

I agree that if it's not throwing any more O2 sensor faults, to try and replace the gas cap. But you would think that if the SES light is on, then there is still an issue and possibly pending fault codes he may be able to retrieve.

carthelosz28

That sounds like the easiest solution so Ill try that first! Thank you. If this doesn't work then ill take it to a shop. I don't have much experience with multimeters:

carthelosz28

So the codes eventually came back on, the 4 low voltage o2s went away when we put in a new MAF sensor. However a p0452 code showed up for the FTP sensor. I took it to a mechanic and he said try replacing the whole pump. I replaced this sensor and he did too just to find out it didnt fix the issue. Should i buy a completly new pump? Ive got a 98 Camaro, so Racetronix has them for around $150. Just tired of spending money without results haha

carthelosz28

Also gas cap didnt fix it unfortunately

G8One2

The FTP ( fuel tank pressure sensor) is not on the fuel pump. Replacing the pump would be a waste of money. The fuel tank pressure sensor is either mounted directly on the fuel tank or mounted inline with one of your evap hoses that attach to the tank. This sensor reads pressure inside the tank, and prevents the tank from rupturing by sensing tank pressure, then sends a signal to the ECM which in turn energizes the purge solenoid or the canister vent to release excess pressure build up in the tank.

carthelosz28

This is my fuel tank pressure sensor which has now been replaced twice. I get the p0452 code, which is this exact piece but it doesn't go away. Alternatively, what could i try to do to get rid of this code?

G8One2

If you've replace this pressure sensor and still have fault codes for it, then you need to check the circuit.

carthelosz28

Thank you. I can learn how to do that. I forgot to mention, when I turn sharp on less than 1/3 tank of gas my car bogs. Like fuel doesnt get to the engine. Im guessing thats fuel pump related but just wanted to get that out there.

G8One2

The fuel pump should be in a plastic sump of its own, and will always have fuel surrounding it to keep cool and supply fuel to the pick up. Bogging when you turn is likely a different issue.

carthelosz28

I appreciate the replies! Yeah feel like i kinda got a lemon lol. I know another thread said someone had a broken wire or something that made the light come on. Ill work on it as soon as i get some time. Thanks a lot!