4jx1

rctr, Mar 18, 6:29pm
How bad are isuzu's 4jx1 diesel engines. Have heard horrible stories about them but what actually goes on them. Is it down to poor design or maintenance or mix of both.
a.woodrow, Mar 18, 6:39pm
Numerous design faults, they have had recalls for injectors, the tips can break off and they run away, the injector seals can fail same result. they end up running away too bad if you're not quick enough to get it into neutral. Oil pressure sensors fail, tracking oil up the wiring harness to the ecu causing ecu failure, and various other problems. They aren't a vehicle you want a bar of, even if you can do your own work, they are just too expensive to fix. Doesn't matter how well maintained they are, or how low mileage either.
franc123, Mar 18, 6:40pm
Do not even think about it at any price, they were the most hideously badly designed light diesel in history that required several recalls to sort issues ranging from electrical wiring filling up with oil to the oil filling with diesel and then running on its own oil, ie you can't shut the engine off or at worst it just revs uncontrollably until it blows up. Nasty to work on, some operations need dealer only tools, parts are expensive and you have to be careful what oil is used in them too. Most were fixed locally by Holden but naturally ignorant idiot importers couldn't resist those cheap Bighorns, Wizards and those silly Mu things that were destined for scrap in Japan and there are examples here that were not recalled, but having said that most that should have lunched themselves would have done so by now.
rctr, Mar 18, 6:47pm
Sounds like lots of fun. Shame cause have seen a nice tidy low milage truck.
a.woodrow, Mar 18, 6:52pm
And I bet it's priced really cheap too.

don't be tempted, you'll regret it.
rctr, Mar 18, 7:01pm
Yeah funny that
mugenb20b, Mar 18, 7:58pm
I agree with posters 2 and 3. A bit of a shame really as they do go pretty well.
969pnz, Apr 20, 2:01pm
A great preforming engine let down by several issues, which if not fixed promptly leads to major problems. Most seemed to fail about 130000 kms.
At 100000km. when changing the cam belt, the injector seals must be replaced, along with an O ring in the cylinder head water supply. Another critical item is the correct oil grade. 5 w 30, absolutely no more than 5 w 40. Injector servicing requires a special tool, which can be made up.
Heaps of info on the net. Most people who run them down have experience of them failing, and faced with HUGE! bills through not having access to good technical info.
a.woodrow, Apr 20, 2:05pm
I run them down because I worked for Holden and saw just how bad they were, even when serviced well
969pnz, Apr 20, 2:11pm
Oh, and the "running away" issue was not confined to Isuzu. when our diesel sent low sulphur spec, engines lost the lubrication value of sulphur and the pump seals failed, contributing to this phenomenum. In fact, many mechanics recommend adding two stroke oil ( without ANY additives, as used in mowers) to assist . about 40 mil per 60-70 litres.
969pnz, Apr 20, 2:19pm
And you will be aware of the horrendous dealer service charges!
I had a 3.1, now have a 3.0, currently importing an OPR sensor. Jx1 needs WAY more attention than JG2, but I love it to drive. considering replacing with a 4JJ1. Thoughts, please?
a.woodrow, Apr 20, 2:22pm
My thoughts are that you really have no clue. Servicing charges weren't "horrendous" at all, and the 3.0 was still a heap of junk regardless of how well it was serviced.
franc123, Apr 20, 2:43pm
That was the tragic bit, they'd eat up and spit out a 4JG2 in terms of open road performance in any of the given models that both engines were fitted to. Much better spread of power and torque.
969pnz, Mar 2, 5:40pm
Check out Oz owner forums re unsatisfactory dealer service. Mostly being an engine needing special service training and tools. not always available away from major centres.