1369666

Hello all.
My wife's 2002 Honda accord, Series J/ 3.0L-(140,000)

Has had a Random misfire condition that has lasted some-time.
First initial thing I did was:

Purchased new spark plugs. Installed spark plugs (NGK_) to MFG specifications (22Ftlbs)
Gap accordingly to the sticker on the hood.
Disconnect battery to clear codes.

This resolved the condition, for 234 miles- the MIL light returned.

In Addition to the Random misfire code; when Cruising at 35 - 45 miles and hour constant, you will feel the misfire, and the engine will begin to "chug" down the road, Puts the kid right to sleep! But Emissions says i cant get the car registered until the lamp is GONE.

I bought a new EGR canister, and cleaned the passage way.
new gasket came with the canister.
Cleared codes via battery d/c.

Code - Random misfire - misfire cyl. one -
Returned; 47.6 miles.

Watching "Eric the car guy" on the popular website "you tube" the ASE certified mechanic mentioned to clean the EGR passages in where the Intake flows into, requiring the removal of the intake.
In addition, the codes I had where from auto zone, mentioning on the slip they provided with the P code (P1399)
Said I may have to do a valve adjustment/ blocked EGR passage.

So in search of the solution, I purchased some sensor safe carb cleaner -
and removed the intake, and removed the valve covers.
Using a toothbrush I cleaned the EGR passages, Intake manifold, throttle body (CAREFULLY), and lower intakes on the lower intake.
Using the specifications noted on the hood, I adjusted the valves - 142536.. .22intake/.30exhaust..

Re assembled with new valve cover gaskets. No new Intake gasket was used.. the old one seems to be in functioning order. . After re-assembly and battery reconnect - the engine started surging from 1500- - 2200 RPMs

Back and forth - constant.

Scared - I researched online as I could not find the answers in Haynes - looks to be a idle relearn procedure.

The idle relearn was performed:
*Drive the vehicle until warm, when warm, turn car off.
turn ignition on 2 times.
then, turn on the car, turn the blower motor on HOT and on HIGH, While revving the motor to 3000RPMS - after 2 minutes of 3000RPMS the Cooling fans should initiate, at this point, I slowly depressed off the throttle, and the engine maintained a 750 RPM idle (no noticeable misfire condition present. at the time.
The ticks from the valve train seemed loud when running the engine, The light came back after 300 miles,
Scared I over tightened a valve or something, I went back in to readjust the valves, found one a bit tight on the feeler gauge, but the rest where fine.
The spark plug hole gaskets are garbage, they crumbled, I have to replace them again!? ridiculous - Did i do something wrong? there was no gasket maker/sealer apon entering the valve covers, so in return, none was applied apon new gasket installations. . .
Apon applying a temp fix for the issue -
The car started, again with the misfire - During the random misfire condition, I disconnected each connector to the on plug coil packs, to which the engine showed no difference in idle during the fault.
There was no batter disconnect performed the second adjustment.
There was no idle relearned procedure done the second adjustment.
EGR passages Had not been cleaned.



Actions I have considered taking in attempt to resolve the Random misfire P1399 Code:

- De-carbonizing my engine:

- Checking the GAP of each NGK plug to ensure the gap is to OEM spec.






The history of the vehicle is not a good one -
So far She has had a reputable shop replace the transmission, As the old one would shift in to 1st - 3-5 seconds after stopping the car. . .

In addition We had been sold the car by a dealer- and when returning the same day was told there was little they could do. This trans *knock on wood* has been functioning as it should, and we have been treating the car nice. Only WOT when emergencies/ highway merging require the WOT to be applied. The car is used in town mostly however, lots of stops n go's.


I hope I have provided enough information, for you guys to help me with my random misfire condition!

1369666

Oh man please help - I have no idea where to start -
But To update my intentions..
- replace the valve cover gasket plug holes next check - I'm sure my "ghetto gasket" isn't working..
- check spark gaps
- perform decarb method if i determine the car to stabl;e enough for the procedure.


The last time i did the covers I noticed a bit of slack in the throttle cable - adjust?

Tonight I intend to pull the codes via the paperclip method - ill be sure to post results if i can get to it on a break at work. . . . .

MAD_MIKE

If the misfire code comes back with cylinder #1 again, swap out the coil with a different cylinder and the spark plug with one different from the coil. This way if you have the misfire come back with a cylinder specific code you can trace it down to a faulty coil or sparkplug. PCM on these Hondas is a bit slow to react to specific cylinder misfire codes. Do a compression check as well to verify there is no internal issue.

1369666

Update- pulled codes again from AZ, Random misfire 1499, EVAP 1457, and misfire cyl 1 and cyl 2.. I didn't get a chance to check plugs n gaps yet, going to replace the valve cover gasket again tomorrow. Would a 1457 cause a misfire condition?

quickname

I have the same problem with an 01 3.0. Cylinders 1,2 and 4. Swapped coils around no good, new plugs no good. First three cylinders in firing order I suspect ECM. Any Ideas?

MAD_MIKE

It is rarely the ECM/PCM.

Verify the EGR ports are clear. Main feed port is known to gum up on 3.0 V6.
http://www.tegger.com/hondafaq/tsb/accord/A99-085.pdf
No need to completely disassemble the upper plenum, just the main EGR feed port needs to be cleaned on the intake manifold.

Verify the valves are adjusted correctly.(Upper intake plenum needs to be removed to access the valve/cam covers)
Honda updated when to check/adjust valves to every 30Kmiles. Intake valves will probably be fine, exhaust valves are usually on the tight side.
Basic hand tools and a lazy Saturday afternoon you can have it done.
Gaskets are reusable if you are careful with removing parts.

quickname

I've never seen a vehicle that one bad coil would cause 3 others to not work. I picked up one new coil and just picked one random coil and voila no more misfire. 38 years and this is a first. Tested and retested so many times I lost count.

Helldawg

Have you checked voltage on the trigger wire to the coil packs?

I have one that is frying the coil packs and was putting 5 volts to the #5 cylinder trigger when the shop told me it should be .5 volts. It's enough voltage that the coil pack is overheating and physically breaking down even with a brand new coil pack.

Had to get ECU rebuilt to replace the coil driver area in it.

quickname

Everything is good. I'm still shocked at one coil causing three others to act bad without it acting bad. Cylinders 1,2 and 4 had misfire codes plus random misfire code and the bad coil was in cylinder 6