I had a lean code but i cleared it and it hasn't come back since but my long term fuel trim 1 says 11% at idle so im running lean i believe. I've had these 2 evap codes for 3 months, p0455 and p0457 and today while i was sitting at a stop light my rpm dropped all the way to 4-500 and almost stalled. Whenever my truck engine is warm at idle the rpm is normal 800 but sputters like crazy. Any suggestions? 2002 ford ranger v6 3.0 auto trans

 

First, the engine isn't and wasn't ever running Lean, thats not what those codes mean

The EVAP codes mean gas tank has an air leak, usual cause is the filler tube has a crack
When it was warmer out did you ever smell gas when filling up?

Stumbling idle could be vacuum leak at EVAP solenoid, and can also cause the codes

Drop in idle could mean time to clean MAF sensor and clean IAC Valve

 

I got some gas today . Its possible that there is gas smell but not certain. MAF sensor is new and iac is new. both are 4.5k miles old

 

the drop in idle is new but the sputter is always on a hot engine

 

Well the drop in idle can only be IAC Valve, that's the only control for idle there is, so either valve is not responding to computer or computer drop RPM because of input from MAF

When was the coil pack last replaced?
The 3.0ls seem to "eat" those up

And idle drop could be spark or fuel related, a stumble that took computer a few seconds to recover from , so not IAC or MAF related

 

i've had the truck for 3 months but i can safely assume everything is oem except the things i've replaced. yea the spark plug wires and coil pack are original. Is it necessary to do oem motorcraft parts? Also swaped out the o2s and no change for the sputter/vibrating engine.

 

For the Coil Pack I think you can use any brand, never read about issues with 3rd party
Inspect the coil pack for cracks, Ford did get a bad batch of them in the early 2000's and there was a serial number range but can't find it

 

what would be the next step if these don't work? I was thinking either bad purge valve or cracked evap hose to cause vacuum leak. I took it to a shop 2 months ago they smoke tested and they said they found nothing. Then again they couldn't find a vacuum leak i found myself.

 

For the EVAP get a hose and a damp cloth....and a helper with good lungs :)
Take gas cap off
Put end of hose in filler and wrap the damp cloth around it to make an air seal
Blow into the hose
Gas tank should hold pressure, it won't because of the EVAP code
So you should be able to hear where the air is escaping

Human lungs can generate about 2psi air pressure, DO NOT use an air compressor for this test or you WILL BLOW OFF EVAP fittings

If air leak sounds like its coming from charcoal canister area, turn on the key, engine off, that should close the air valve on canister

 

hey Ron,

ive these codes too and im chasing it down. Ive a lean #2 bank with longterm fuel trim on that side at 20-24%. Ive searched felt, smoked and sprayed everything more than once trying to get rpms up. Nothing

today i had access to a fancier than mine code reader from snapon. Its smarter than i am im sure but the point being it lists codes by application Engine- zero codes and evap 2. It allows a evap test so i figured why not? It failed. Theres a purge valve on/off switch, i turned it off Engine immediately stumbled and died woukdnt fire up until i turned it back on...

is my evap system causing a lean condition on bank 2? Am i looking at the engine when the issue is somewhere else? Namely the evap system? Can i pressure test that somehow?

im also throwing a fuel pressure sensor code but i dunno how im going to check that with out the box off. Someone mentioned monitoring the voltage and pulling the gas cap off to see a spike to 5v....