2001 HZJ79 diesel, 35,000 kms. Truck is occasionally running rough, sputtering and giving off some blue smoke. This is more likely to happen when starting out for the day. I have cleaned the fuel tank, changed the filter, bled the air out of the system and run some injector cleaner through it. Better but still happens occasionally. I went to a diesel shop today to inquire about getting the injectors cleaned / rebuilt and that was a hard pass on their part. I've looked at some after market injectors and they are pretty reasonably priced. I generally am not one to just fire the parts cannon but a whole set for $300 is about 2 hours of shop time IF I can find a shop that wants to take on the job. Open to any and all suggestions, tips or advice.
Think I need new injectors
- Thread starter rst277
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JDM Journeys
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Bled the air... Was there in fact air in there? How did you know? From where? Typically air in the system manifests in whitish/gray smoke as opposed to blue, but those colors can be hard to really define...
As far as injectors, my advice would be to have yours rebuilt even if you have to send them away. OEM injectors are generally superior to anything aftermarket. And if you want all new you can still buy them brand new. Not super cheap but they'll likely last another 200k kms or so.
And if you do replace them, maybe consider doing them yourself? If you are careful with the washers and follow instructions, it's not that hard.
Before you go through any of that though, it wouldn't hurt to run some cleaner through them. 2 bottles of LiquiMoly diesel purge (skip the fuel system and run it straight off the bottle) could make a difference. At 30k kms its probably suffering from lack of use rather than wear as I'm sure you've surmised... Diesel purge will work on the injection pump too. It's not magic but if it's just a little carbon build up you might get lucky? (Or maybe I should say LUCKIER? You do already have a 79 after all).
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It is helpful when posting a problem like this to mention when the issue began and if there was anything done to the car just before.
Injectors are very simple mechanical devices and do not give intermittent issues. And at 35,000 km, there should not be any issues with them unless the vehicle has been run on very poor fuel or has stood outside for years without being used.
Aside from genuine NipponDenso injectors from a reputable supplier, avoid aftermarket injectors. A lot of junk out there.
Your problem lies elsewhere in my opinion. Most likely air in the fuel system. There are many threads on here which discuss how to diagnose this.
If the engine has recently been worked on, timing might be the cause.
Injectors are very simple mechanical devices and do not give intermittent issues. And at 35,000 km, there should not be any issues with them unless the vehicle has been run on very poor fuel or has stood outside for years without being used.
Aside from genuine NipponDenso injectors from a reputable supplier, avoid aftermarket injectors. A lot of junk out there.
Your problem lies elsewhere in my opinion. Most likely air in the fuel system. There are many threads on here which discuss how to diagnose this.
If the engine has recently been worked on, timing might be the cause.
- Thread starter
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I imported this truck in March. It is the fire truck version with PTO. I drove it from Vancouver to Winnipeg and about 4 hours into the trip, the truck started running terrible, tons of blue smoke, bogging down, sputtering. I had just filled up the tank after running it almost empty so I figured it was some bad fuel or junk from the bottom of the tank. I bought some Stanadyne injector cleaner, poured it in, prayed and hit the highway. Symptoms cleared up after a short period but still some rough running and blue smoke on start up. On getting home I have changed the fuel tank, changed the fuel filter and purged the air out. I believe there is no air in the system because the priming plunger on the fuel filter housing is tight but I did not bleed air out to the injectors. Perhaps there is air in there?
Thanks for the suggestion!
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- #5
I am thrilled by the truck and am looking forward to putting it to work. This truck only drove about 1500kms per year according to the annual safety sheets I found in the glove box but as a fire truck I could imagine it spending a lot of time idling to run the PTO. I think I will confirm there is no air in the system by cracking the injectors and checking for any bubbles. The diesel purge right off the bottle will be the next step. It runs great 99% of the time so I'm not panicking but of course I want to sort it out so the truck as runs as well as it should.
Thanks for the advice!
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You won't be able to detect air by cracking injector nuts - that is only done to bleed them. Replace the hose from filter to injection pump with a clear hose and check for bubbles.
Sounds like another case of a 1HZ not liking our Canadian diesel. I have now experienced it with two of mine, one of @John Young’s, and recently a couple from Australia was driving theirs and had the same issue.
I run additives now or UFA Dieselex Gold and am happy.
I run additives now or UFA Dieselex Gold and am happy.
TreadingLight
"Overlanding is Sh*t"
You say blue smoke but you're chasing fuel issues. This is inconsistent. as @JDM Journeys pointed out, blue is burning motor oil.
Are you sure it's blue and not white or grey?
Intermittent smoke sounds like air entering the fuel system, but that would not be blue.
Are you sure it's blue and not white or grey?
Intermittent smoke sounds like air entering the fuel system, but that would not be blue.