BrettBaker

Hello folks, I'm new here but have been reading your forum to work on the wife's 99 Accord for some time. At one time I was an ASE Master Tech in both car and heavy truck so I know what end of the wrench to hold, but walked away from the biz about 8 yrs ago. I'm hoping I might gain a little info. I got a P1457 6 months ago and like alot of mechanics, blew it off until NY inspection came due and had to repair it. I went to the dealer to buy the valve know for corroding and the parts guy told me that their mechanic just go ahead and replace the vent shut valve and the soleniod valve (#7 &#8 on parts microfish) and the cannister. I went ahead and replaced them and the tank immediately held pressure or vacuum, which it hadn't before. Unfortunately, 50 miles later it threw the same code. I read here or somewhere that there were problems with it frying the ecm due to one of the valves shorting. Is there a way for me to test this with a multimeter, and if so how. If not and I must take it to a dealer I have a few other questions. If I get a used ECM what do I have to do about the damn keys! Do I need to have the dealer install the ECM so they can flash it? If anyone can think of anything I may have overlooked please chime in. I have not tested the purge control valve but but according to the parts microfishes, my 4 cyl doesn't have one. If it does, I will test it tommorrow. The dealer also told me that the valve on top of the tank rarely goes bad and if it did, it shouldn't let the tank hold pressure. I did run it along time with the corroded valve and the light on so I am afraid it is the ECM. Are there any tricks to fooling the ecm to pass emmisions test? I read the TSB and they mention a "good will" possiblity, my car has close to 150K, any chance of "good will" from Honda? Any and all help would be appreciated!
Thanx,
Brett

BrettBaker

Anyone?

casper.hughes

does the car start and run

BrettBaker

Everything runs great. TSB's and tech have said the ECM gets damaged by the shorted soleniod and will repeatedly throw the code

P_Adams

A very common late 90's code, P1457 is a failure in one of the evap system solenoid valves. There are 2 culprits, the Vent Control Valve & the 2 Way Bypass Valve. They short out due to corrosion/contamination from water seeping into the valves. Of the two, the real culprit seems to be the 2 Way bypass Valve. I would also have the Gas (fuel) filler Cap checked. The P1457 can be also set by a loose / defective gas cap as well.

As far as the Honda "Good Will" consideration; It won't hurt to ask.

P

casper.hughes

ok then i believe if there was something wrong with the ecm that the car would run bad or if at all but idk k.a.m and see what happends

ekb16

iTrader: (1)

it took me about 2 months to figure out my p1457 problem on my gsr swaped civic...turns out the evap bypass sol. shorted and fried the evap purge circuit at the ecu, replaced my ecu and fix the problem.

u should check all 3 of ur solenoids.. Purge control sol, Canister vent shutoff and bypass sol..put 12 volts to it and see if they all click..also check ur bypass valve which is usually connected to the bypass sol., make sure there isnt any water/gas when u take it apart from the sol.

i found out my ecu was fried bcuz the purge control sol wouldnt duty cycle when the engine was warm..i found this out by jacking up the front of the car, warming up the engine (fan comes on), putting in 1st and reving the car up to 3k rpm and when u pull the vacuum hose from the purge control sol to the evap canister u should be able to here/feel vacuum from that hose as it is duty cycling..i also hooked up a volt meter to my ecu at the evap purge and had a constant 12v and wouldnt change when i rev it up in gear

hope that helps..that was just my problem those there is also other things that can cause p1457

not always thats wut i thought at first but my car ran fine with no problems

postman

check your vent tube for dirt or spider webs

BrettBaker

Gas cap was checked and like I say the tank seems to hold vacuum/pressure. From what I understand the damage done to the ECM does not affect the wayu it runs, it just does not allow the evap system to test properly. There are a few TSB's including 03-001 discussing this but they use honda's PGM tester to diagnose. I was looking for a way to "breakout" the ecm and test for this issue with a multimeter. i'll try the test you mention ekb16. I will also check the vent tube. Thanx guys, keep em comin'!
Brett

Eagleman

The canister vent shut valve or the EVAP Bypass Solenoid Valve could be the problem, as the culprits easily get corroded in geographic locations that use a lot of salt on the roads in the winter. Honda had to redesign the parts to address this problem.

TSB's ( Technical Service Bulletin's ) 01-011 ( EVAP Control Canister Vent Shut Valve 98-99 models ) and 03-001 ( EVAP Bypass Solenoid Valve 98-02 - depending on the model ) address these problems and explain that if left unchecked could damage the PCM ( computer module ). It has nothing to do with the gas cap as that would be a P1456 code.

If the car is a 97 Honda, the warranty on the emissions system has been extended to 10 years or 150,000 miles. See TSB 98-081 (97 only ).

The EVAP Control Canister Vent Shut Valve is easy to find and replace youself. And if your lucky and can persuade the Dealer to fix it, they can replace it using goodwill ( free ). They don't do it always, but it can't hurt to ask. This is also mentioned in the TSB's.

But if you want to do it yourself, and it may take less time than bugging them, and is fairly simple. Just be careful of the two screws that hold it ( EVAP Control Canister Vent Shut Valve ) in place as they are probobly badly corroded. Spray them with some break free, if they give you a hard time, rather than taking the chance at snapping them. But you won't know till you look at them, they may just come right out, but i just wanted to warn you. The bottom of the car get abused by all the rain and salt it is exposed to over the years.

I have all the TSB's as well as EVAP/ fuel system diagrams, if anyone needs them just contact me. The TSB's have good diagrams as well and show you a lot of detail.

Here's a link to another discussion I started awhile back about this problem.

http://forum.mpt.org/messages/9/6923.html

Good Luck!!!

rival04

I have the p1457 on my honda civic si(2000). already i have replaced to canister vent shut vale solonoid..but 2 days later the light is back.. would you reccomend the bypass solonoid and 2way bypass valve next? where are they? do you need to remove the gas tank to get at them? and another note..i have read around and would it be possible that somehow overfilling the gas tank would have caused the problem? what should i do?

Turbowa

Before replacing the computer. I would check to make sure none of the plastic connectors by the fuel tank are cracked or broken. It would also be a good idea to replace the canister filter along with the purge control solenoid. The purge control solenoid is located on the intake manifold. Its just under the throttle cable. There is also a sorta check valve right before the solenoid. Make sure there is nothing obstructing it.

The P1457 code is kind of generic. Its just states that there is a evap leak canister side. This is a pretty broad area to be looking in.

Turbowa

Yes over filling the gas tank can cause this. Thats why its recommended to not top off your tank when getting gas.

Eagleman

Over filling the gas tank or putting on the gas cap on too loose usually results in a P1456 code.

ironlung78

bringing this back from the dead...
maybe someone can point me in the right direction...

at what point does the canister vent valve open and close???
i was able to blow air through the vent valve by (1)removing it from the cannister and disconnecting it from the harness and (2) with it removed from the cannister and connected to the harness with the engine running at idle...


original symptom was blowby under my gas cap lid, so i replaced it with an OEM Honda cap ($45.00 at dealer) and the code returned within 15minutes...
after driving around for a few weeks with the new cap i no longer here the vacuum when i unscrew the cap to get gas, and my B&M fuel pressure gauge on top of my fuel filter reads next to 0 pressure after the engine is off...

phootbag

A faulty fuel cap will set a P1456 not a P1457. There are more possibilities for a P1457 than two faulty solenoid valves.

phootbag

The Canister Vent Shut valve is only used during self-diagnostics. The vent valve is always open unless the system is being checked.

Again, a fuel cap will never set a P1457.

The EVAP systems on these cars can be tricky to diagnose. There are a lot of variables that can cause an EVAP DTC. The quickest way to diagnose any EVAP malfunction ( EVAP DTC's should be treated as malfunctions not leaks. "Leak" in the DTC description is misleading because leaks aren't the only thing that can set these DTC's ) is with a scan-tool which allows the technician to use the ECM command to operate the various valves while monitoring the Fuel Tank Pressure sensor voltage, proper knowledge of the system and between 1-2 hours of labor. There hasn't been an EVAP malfunction I couldn't fix, yet.

phootbag

I have actually developed a method of testing these systems that allows MOST diagnostics to run between 10 - 30 minutes.

clevelandohd

I have a 2000 Accord. The engine light came on with the P1457 code. I searched on the internet and found that it was likely the valve under the car, if not then the computer. I tested the valve, it was fine, but did not close when it should. So, it probably is the computer. I would have liked the dash light off, but it was not worth the hundreds of dollars for a new computer. So, I waited until I had to get an emissions test. I decided to try to fool the computer. I took the valve off, and put a cork in both ends (in one end there was a leak in the valve and I was not sure which end pressure was measured from for sure). Anyway, the that was about 150 miles ago and no dash light. The other two times I reset the engine light, it came back on within 25 miles. If the light comes back on for P1457, I will update this.

butch burton

I have a 97 accord with 326K and have been having ecm 1457 for a couple of years. When the temp is below 60F, I get the code. Replaced the rubber intake pipe - it had a broken connection and still got the code. My accord was in snow country for several years and salt destroyed a couple of radiators and exhaust systems. This AM I saw the screws holding the intake covering the air filter had rusted out. Just took a chance and inserted a coated wood screw and viola. The ECM system needs the full vacuum created by the engine to function. I was about to start replacing switches on the ECM and those things even on line area pricey - + $ 700.

BTW having the ECM light on hurts nothing - just won't pass the annual inspection. Also I replaced plugs this AM after 75K. The local autozone on line inventory said they had the NGK plugs in stock - they didn't and the manager cut the price of the platinum to the copper price.

Only change I had to make was to go from 5/30 to 10/40 hi mileage oil and change every 10K.

Butch

mikespike2

I had a bad EVAP solenoid, the solenoid near the left rear wheel under the car. The common failure where the coil shorts out. I ignored it for months, and it destroyed the driving transistor in the ECU.

I ordered the transistor from eBay and replaced it myself. With a new valve and new transistor, it now works properly.

Been intending to make a writeup with photos about it...

rodav8

mikespike2, I'm guessing you haven't got around to the write up with photos on replacing the transistor in the ECU yet?