atomical

2001 Accord V6 EX

A few months ago I got a P1457. I pressure tested the evap system on Sunday using Honda HDS. I tested that each Solenoid clicked. The weird thing was that in the 'Single Solenoid' menu I couldn't get the purge control solenoid to click without going into the multi-solenoid menu and turning on the other solenoids as well. My thought was that it was an oversight or documentation error. But perhaps my purge solenoid isn't grounding properly.

I drove back to Chicago (2 hour trip) on Monday and drove to work and back (45 minutes each way) on Tuesday. On Thursday I got the car out of the garage and started to feel jerking from the engine and the check engine light started to flash one mile down the street. I quickly got the car back to the garage, read the code (P1399) and hooked up the HDS.

I'm trying to figure out if there is something with the evap system that I touched that could cause this to happen. It appears to be running extremely lean so my first thought is that the fuel pump might be going or there is an obstruction in the fuel line. I was working specifically with the two way bypass valve on Sunday. I know the fuel tank pressure sensor is right above the two-way valve. Could there be an issue with incorrect readings from this sensor and how can I prove it?

I also disconnected the wires that go to the EGR valve. The misfiring happens during idle too so I don't think the issue is EGR. I don't know if it's possible that the P1399 could prevent other tests (i.e. EGR) from running and if my EGR ports could be clogged. I'm trying to avoid assuming or guessing and work with the data that I have.

I'm not driving my car to work because I don't want to damage the catalytic converter. So for now I'm only turning it on briefly for diagnostic purposes. Here's a package with some screenshots from HDS. I'll probably have some more data tonight. I've searched for and read hundred of threads on random misfire issues but I don't know whether my evap issues and this issue are related.

https://www.dropbox.com/s/e6j5dn82on...age-public.zip

0go-part

Check for a vacuum leak or any broken vacuum hoses.

http://www.odyclub.com/forums/24-199...ere-start.html

DCFIVER

P1457 pertains to a leak on the canister side of the evap system. The reason for testing the solenoids is to see if they are stuck or stick open. If during your testing you accidentally got a valve to stick open there would be little to no effect unless it were the purge valve. In which case the vehicle would run slightly richer and nothing more.



Your screen shots are admirable,but ultimately worthless. I need to see live data, not freeze frame or DTC descriptors...

atomical

I'll work on getting those. I took out the coils yesterday. The two I took out to examine have hairline cracks near the top. Should I replace these?

http://db.tt/pnN7xoT0

Also, I ordered a tool to test coil plugs. I was surprised to learn that some mechanics use an oscilloscope to test coil plugs.

atomical

Here's a capture from HDS. How long do I need to record data for it to be useful? Because the check engine light has been flashing on/off I've been running the engine for short periods of time while testing.

https://docs.google.com/spreadsheet/...2c&usp=sharing

DCFIVER

A scope is the most complete tool to use. The firing line and oscillations that follow tell the whole story. However it takes a few years and lots of practice to master this technique. In your case you can simply move the coils to another cylinder and see if the misfire follows....(also,I did not notice any cracks)

DCFIVER

Are you using the HDS via a laptop or hand held scanner??

atomical

Laptop.

atomical

Last night I tried out the Hickok/Waekon coil tester. The first coil I tested was bad. I moved it to another port and tried it again to confirm. The others may have had different firing patterns but once I knew one was bad my plan was to replace them all. The car has 180k and I'm not sure if they've ever been changed. I ordered the coils using Honda Parts Now.

I'm probably going to pick up a spare (non-OEM) coil locally today so I can start driving again and then keep it as a backup in case this happens in the future.

Does anyone know if there is a way to record misfires? Either with HDS or generic OBDII?