OBD code p0456 how to fix?
for several months I get a occasion CEL which comes on and usually stays on for several days, I have a code reader and repeatedly have gotten just code P0456 and have cleared it out which last for a bit and then it just comes on again whenever. No problem with how the jeep runs this is a 2000 XJ all stock powertrain 123K. I initially thought this was a bad gas cap again, which I went through years ago and finally replaced but when I googled the code I found this type of info instead. Apparently this particular code is in reference to a very small leak of the Evap system and i'm guessing that I have a loose of pinched vac line somewhere, my problem is how to I go about methodically chasing this down???
The LDP, (leak detection pump) is located in the left/front corner of engine compartment below the air cleaner housing. It is mounted to left/front inner fender sheet metal. The LDP and LDP filter are replaced (serviced) as one unit.
But you will want to check all the vacuum lines and hoses before you replace the pump. Here is a service bulletin that will explain it better than I can.
As far as it being expensive..I don't think it would be all that much, but you have to get it from the dealer, so, that's up to them. That's how they get us, (lol)
EVAP System - Leak Detection Pump Misdiagnosis
GROUP: Vehicle Performance
DATE: Feb. 4, 2000
Misdiagnosed Leak Detection Pump Systems With DTC P1494, P0442, P0455, OR P0456
1997 - 2000 (AB) Ram Van
1997 - 2000 (AN) Dakota
1997 - 2000 (BR/BE) Ram truck
1998 - 2000 (DN) Durango
1997 - 2000 (FJ) Avenger/Sebring/Talon
1997 - 2000 (JA) Cirrus/Stratus/Breeze
1997 - 2000 (JX) Sebring Convertible
1997 - 2000 (LH) Concorde/Intrepid/LHS/3OOMNision
1997 - 2000 (NS) Town & Country/CaravanNoyager
1997 - 2000 (PL) Neon
1997 - 2000 (PR) Prowler
1997 - 2000 (SR) ViperNiper GIS
1997 - 2000 (TJ) Wrangler
1999 - 2000 (WJ) Grand Cherokee
1997 - 2000 (XJ) Cherokee
1997 - 1998 (ZJ) GrandCherokee
During evaporative system diagnosis, Leak Detection Pumps have mistakenly been replaced. A thorough inspection for pinched, kinked, or disconnected supply vacuum lines (as currently listed in the Powertrain Diagnostic Procedures) is a critical step in diagnosing DTC P1494 (LDP SW OR MECHANICAL FAULT). Additionally, the other evaporative leak faults (DTC P0442 - SMALL LEAK, P0455 - LARGE LEAK, and P0456 - VERY SMALL LEAK) should have the supply vacuum lines examined for pinches or kinks prior to any LDP component replacement.
Anyone been through this?