Has your car been running poorly?

Did the check engine light turn on right after some sort of service on your car? You mentioned that you already went through a whole tank of gas, so bad gas is unlikely.

Here is a video for diagnosing misfires:

1997 Nissan Altima Misfire Diagnosis -EricTheCarGuy - YouTube

Have you checked for exhaust leaks? Here is a good video:

 

Check w/ Autozone for a fuel injection pressure measurement tool for rental. I used this to measure fuel pressure on Celica. I had to cut the fuel supply line to insert special fitting (no fuel pressure tap anywhere). Afterwards had to splice fuel line (very difficult to splice nylon fuel line). Honda's can usually be connected either on fuel rail or at fuel supply connection to the fuel rail.

After reviewing 03-06 Shop Manual, it looks like V6 setup resembles the Celica and may require either a special tool or splicing the line as I did. An alternative is to purchase a spare fuel supply line from salvage yard and modify to measure fuel pressure. Given this difficulty, you might consider simply cleaning the injectors.

Working on fuel injectors is easy. See extensive youtube videos. You may need to gang several batteries in series to get enough voltage. I req'd three to reliably open the Celica injectors. I would avoid holding them open for long periods w/o flowing through them for cooling. I held them open, flowed throttle body cleaner, and then air from rubber tipped air gun to blow through. No need for matching electrical connector to mate to fuel injector. A set of small insulated alligator clips will work fine.

Celica has 1.8L, 1zz engine.

good luck

 

Okay, I will redirect from checking the fuel supply pressure to cleaning the injectors.

The car doesn't have a window of downtime large enough to do this for a few days.

Typically do all six injectors go bad at the same time?

I had a Celica way before yours. It had the 20R engine which went 150,000 miles with basically nothing other than routine maintenance and a timing chain. It probably would have gone a lot more.

 

I have read through the Haynes manual sections on removing the upper intake manifold and removing and replacing the injectors.

I have watched several YouTube videos on cleaning the injectors.

I would appreciate the view of someone who has tried this on whether I should replace or try to clean myself, or if I should have someone else do it.

Factors to consider:

This is my only car. If I have a problem, or haven't fully prepared for a task getting parts, taking too long on the job so the car is needed can really be an issue.

I haven't replaced or cleaned injectors before. I am slighly above average for most car repairs. Doing something the first time will take me longer than most, I tend to be a bit of a perfectionist and would rather do it right than quick.

Injectors from Honda are expensve, the estore prices OEM ones at $57, a total of roughly $380. Rock Auto sells a new Standard Motor Product one at $31 or a total of $211, they also sell a remaunfactured BECK/ARNLEY model for $42 for a total of $285. Then add another $30 to each for the gasket. So from $250-$410 for parts. I can't tell what company makes the OEM brand for Honda, otherwise I would price theirs directly (like NGK for spark plugs or NTK for O2 sensors).

A rebuild kit (for example here Top Feed Kits - Mr Injector Parts) is $70. Plus another $30 for the gasket. For a total of $100.

The third alternative is to just try to clean them and try to reuse the injectors, this would still cost $30 for a gasket.

I think it would be wise if I ended up deciding to clean or self rebuild to have some new injectors on hand just in case something happens to a couple of them.

Like everyone these days, cost is an issue for me right now. I don't have a built out workshop. Just a standard garage and most basic tools. I have a torque wrench but do not have a vise.

Is replacing them something I should attempt myself? If so, how much more does it add to the complexity/job length to try to clean and reuse the old ones?

Thanks for sharing your thoughts.

 

I would avoid throwing parts at the car. I doubt that you clogged all 6 injectors at one time.

Use a mechanics stethoscope (or a piece of hose for a poorman's version) and listen for clicking on each injector. Maybe try Chevron with Techron or Lucas fuel injector cleaner.

You mentioned that you had a code for the catalytic converter for a long time. Do you know the actual code (P0420, etc..)? I clogged catalytic converter could cause you issues.

Remember, keep diagnosing before replacing parts, or this will become expensive. You may want to get this diagnosed by a shop.

 

I bought a mechanics stethoscope. I will try to listen to the fuel injectors next. My best guess is that I can access 3 of the 6 without removing the intake manifold. Once we know those results we can decide if it is worth removing the intake manifold to listen to the remaining 3.

This is what I said earlier regarding the cat converter initiated CEL.

I have had an intermittant CEL light come on. I took it to the Honda dealer, they told me that a catalytic converter needed to be replaced. I did not replace it at that time. During this time, the car has been driven like an old lady. A few miles each trip every few days and very lightly driven. When I drive longer distances, the CEL light would go away.

My driving habits changed substantially roughly when I started seeing the cat cov CEL. Prior I was driving 50 miles/day. More recently I have just been making much shorter less frequent trips. As I said above, when I get the CEL tied to the cat conv it would go away by going on an extended drive. I suspect that the cat just isn't heating up enough to do it's job before it gets turned off. It has been a while, but I think that the code was P0420. It was the cat for the rear cylinder bank.

 

The catalytic converter should work properly regardless of your driving habits.

Does the check engine just turn on or flash while driving?

 

Unless you don't think you can clean them, there is no reason to replace them. Cleaning should work. However, I checked the Honda Shop Manual and removing the fuel injectors does require intake manifold removal. There is a good video on intake manifold removal of V6 by ericthecarguy on youtube.

Before doing this job, some additional diagnostics and discussion are indicated.

Did you review the TSB I linked earlier in this thread, TSB 04-042. It appears to be on point for your problem. Can you detect engine missing at any time?

Does engine miss cold and smooth out when fully warmed or missing continually? A single blocked injector can result in over-lean condition on cold startup (missing), but will be compensated by fuel management w/ long term fuel trim and smooth out when warmed. However missing would be on the blocked injector only. Since you have all cylinders indicated, this suggests either all injectors are partially blocked or something else (ECM) causing miss notices.

The injectors are likely electrically OK. A faulty electrical circuit is detected and a MIL code set for faulty injector. However partially blocked injectors won't set a code and might cause your symptoms.

The following thread appears to be on-point, and points towards valve adjustment as likely. This is DIY job.

http://www.mdxers.org/forums/14-prob...sfiring-2.html

good luck

 

Just me....can you swap the coils from the back to the front and see if the "noise" moves. I have seen A coil go bad and then cause multiple miss fire codes. Cheap and easy "try"?

 

Okay, here is an update. With the mechanics stethoscope I listened to the two fuel injectors on cylinders 1 and 4. They sound likely they are operating correctly, I can hear them clicking as they open and close. I can not reach more fuel injectors without removing the intake manifold.

I was also able to isolate the frequent non normal ticking noise I have been hearing. It was coming from the EVAP purge solenoid. So I guess my next question is, is htis noise a symptom of the issue, or the actual problem? What should my next steps be?