'04 Honda Accord V6 Fuel Injection question

[86cutlass307]

Happy Christmas Eve everyone,

I have a high mileage Accord (192K) that my wife drives, puts alot of highway miles on for her work. I have wanted to send the fuel injectors out for ultrasonic cleaning and flow testing and just wanted to get some feedback from folks that have done this and what your results were.

Car has been idling a little rough on the first cold start of the day for a couple of months now. Background - plugs, O2 sensors, vacuum, compression are all good and I clean the throttle body periodically, valves adjusted at 155K. Thanks in advance for your time and I hope you all have a Merry Christmas.

 

[TexasHonda]

Is miss random or put-put-put (same cylinder). Random miss is unlikely to be an injector miss. Injector cleaner is in autogas now and problems are rare.

More likely to be valves or EGR system (V6 and I4 are notorious for problems). If it misses cold, suspect a leaking EGR valve.

PCV should be checked closely also.

good luck

 

[Dan55]

Coolant temp sensor?

 

[86cutlass307]

Thanks for the quick reply, I changed out the PCV valve at valve adjustment, it didn't look too bad but changed anyway and it was a Honda part. The roughness is random more or less.

While the top was apart to do the valves, I cleaned all fuel/oil vapor varnish from the upper intake and decarbonized the EGR tube that is inside the upper intake. I cleaned the lower intake tubes where the injectors install as best I could without flooding with cleaner spray ( not too bad looking but heavier varnish than upper intake). The intake valves were absolutely spotless, Redline SI-1 does work folks! I also coated a small cleaning brush and repeatedly swabbed the EGR tube on lower intake on the front assy. that runs down into the cylinder head. Not much I could do but I did clear a little bit out. Piston tops only had a thin veil of black/gray on top, no heavy carbon.

It still has the orignal EGR valve installed but hasn't dropped any codes and we are the orignal owners. I guess I should pop the EGR valve off and take a look. Sucks, those are expensive.

 

[artificialist]

Originally Posted By: 86cutlass307

It still has the orignal EGR valve installed but hasn't dropped any codes and we are the orignal owners. I guess I should pop the EGR valve off and take a look. Sucks, those are expensive.

Adding to that problem, I have seen many aftermarket ones that don't do the job, so there is no way to save money there.

 

[hsd]

Could be the motor mounts are getting tired and not absorbing the engine vibration like they used to. I dont remember if the 04 Accords used a vacuum operated mount or not.
It could also be just the winter blend gas that is causing the rough idle.
I doubt ultrasonic cleaning the injectors is worth the trouble at this point. If the problem gets worse pick up some rebuilt injectors and swap them out.

 

[86cutlass307]

You know, I forgot about the winter blend, we buy gas at the same place all the time - ethanol free. This car does have the vacuum solenoid controlled front motor mount. I changed the motor mounts out this past summer and the trans mounts were changed in October when we had a reman'd transmission installed (another thread). I have about 2K miles to go before I do a drain and fill and send a sample off for testing and pull the little filter for inspection.

Usually the gas isn't in the tank long enough to draw moisture but maybe we got a batch that wasn't up to par. I'll follow up after I pull the EGR valve for a look and I'll post some pic's.

Thanks and Merry Christmas all!

 

[mechtech2]

I'd use a good in tank cleaner for one or two tanks before having the injectors worked on independently.