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Trooper 3.0 DOHC Diesel VJX1 problems with surging/dirty gas

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Trooper 3.0 DOHC Diesel VJX1 problems with surging/dirty gas

Postby bionemesis » Mon Feb 08, 2021 11:15 pm

Hi all,
I'm Greg and need your help. I am a medical professional who has become knowledgable about my problematic car.

I appreciate your help in advance.

I'm needing help the following issues that I'll list briefly, and then discuss in more detail.

1. Intermittent Engine Surging/Sputtering/accelerating in setting of diesel tank that appears to be mixed with oil.

2. Loss of power and intermittent Check engine light (with no codes stored) when accelerating slowly, but no problem when accelerating quickly

3. Several recent clogged fuel filters, and recent cleaning of diesel tank because of heavily contaminated diesel-appeared to be admixed with oil

Background:
I’m an ex pat living in the Philippines. Where we live currently we are 10 hours from quality Isuzu service centers, and mechanics very skilled with automatic transmission vehicles. This hasn’t always been the case. In our current location very few individuals have the knowledge regarding the care and repair of automatic transmissions.

In a separate and more urban city, I purchased in September 2017 a 2003 Trooper LS Automatic 4 x 2 diesel with a 3.0L 4JX1 (specifically 4JX1-988340) with sunroof @ 139,000 KM/86,000 Miles and within days noticed that the engine was running quite rough. The Isuzu service center changed all fuel injectors including fuel inlet gasket, sleeve gasket, nozzle gasket, injection nozzle gasket, and injection nozzle ASM. At that time the vehicle smoothed out and ran smoother (still not as smooth as would be expected). A few months later @ 141,000 KM/87600 miles I noticed that the car was losing power intermittently at any speed or acceleration and would the problem would remain until I turned off the vehicle and then turned it back on. At that time the problem would usually not recur that trip. I took the vehicle into the same center and the TECH 2 computer scan revealed problems with the Intake manifold absolute pressure sensor. They suspected that the sensor had lost contact and needed to be changed. I changed the sensor and the once intermittent and unpredictable problem then became a regular but predictable and correctable problem. Every time I now stepped on the accelerator that the if I stepped lightly and slowly accelerated that the check engine light would come on and the car would lose power. It appeared that it was slow to shift. The Check engine light would stay on until the car returned to less than 1000 RPM, at which time the car would return to normal power until the car accelerated past 2000 RPM and the above problem would recur. I also noticed if I used more acceleration than appropriate that the CEL and loss of power wouldn’t occur, and this is how we have been driving this vehicle until a few weeks ago. We visited the ISUZU repair shop multiple times over the next year, and they were happy to charge me fees to assess the vehicle but no one was able to diagnose the issue. Their advise was to drive 24 hours to the nearest metropolitan city to have the issue addressed. This wasn’t able to be accomplished. As a side note we found out that despite a dozen or more check ups over the 18 months we lived in that city that not once did one of the ISUZU mechanics test drive the car before or after their evaluations.

We found another highly regarded mechanic in the same city who suspected that the engine needed to be overhauled. They overhauled the engine and removed a few aftermarket parts that the previous owner had installed. Their comments were that these parts which were added to optimize combustion and increase gas efficiency left thick carbon deposits throughout the engine. The mechanics laughed at how much carbon build up was present.
The car had no new issues until September of 2020 when we began to notice engine surging. It began when the car was idling that the RPMs would rise to 1200 or 1500 RPMs. The car would also surge while driving, usually at lower RPMS and speeds but it was intermittent. A local mechanic friend assessed the engine surging and found that the fuel pump was broken, the fuel filter clogged, and the fuel was silver grey with metal like particulate. After his repair the surging resolved and drove as normal (still not normal but more than functional for a 17 year old vehicle).

The vehicle began having problems with hard starting in December 2020 and it was found to have a bad glo plug relay and 3 out of 4 bad glo plugs. The mechanic, rather than recommending purchasing new relays, rerouted the wiring to the heater relay because, “You don’t need the heater in the Philippines.” Within days these three glo plugs failed again, and were replaced and again failed. I then asked them to purchase new relays and replace the relays and glo plugs. We are currently waiting on parts, and I suspect I have no functioning glo plugs currently. To currently start the car (even in the tropical climate) I have to plug the exhaust and after almost starting the car initially. Try once more with a lot of pressing the accelerator. The car then is able to start.

Beginning two weeks ago the engine surging, acceleration at random, and car shaking begain intermittently. If I accelerated quickly (punched the gas pedal) the exhaust would belch a lot of smoke and the car would drive better. I took the car to the shop and they said that the fuel filter was clogged, changed the filter and then said that the gas in the filter was black like oil.

I had the tank removed, and cleaned and the tank was full of black full. The mechanics there said it was from bad gas from the station, but using only the highest quality diesel from the best local gas station I suspected that it was somehow diesel and oil mixed together. After a lot of talking to other mechanics and research I realized that the 4JX1 engine is prone to common rail injector failure and injector seal/sleeve failure commonly mixing either water and diesel, or diesel and oil.

The car drives better than last week but still spits, and sputters, surges, and accelerates at random. It seems to do this more at lower speeds and RPMS, and improves at higher RPMS. The car can go into full wanted to accelerate when stopped, and me depressing the brake is all that is keeping the car from moving forward. Other times it can drive completely normal. I’ve found that if I slowly accelerate and keep RPMS below 1200 or so that the misfiring/engine surging/acceleration problems don’t occur. It seems that around 1500 RPMs or if I quickly accelerate that the car surges/shutters/accelerates at will.

Of interesting note is that the problem with CEL and loss of power if slowly accelerating is still occurring even with the new engine surging. It seems that the engine surging doesn’t occur if the CEL is on from slowly accelerating and loss of power.

The mechanic that I found today who is knowledgable about this engine and it’s notorious problems thinks the fuel injector sleeve/o rings are bad and that Is why the diesel tank is full of oil and why the car is having so many problems with surging etc.

I know this engine has many problems: EGR valve going bad/bad CPU/Fuel injector and seal failure with mixing of oil/diesel/H20, and problems with the turbocharger.

The mechanics here are afraid of automatics and tell me that they can’t help me. I know of some willing to help: ie. Clean the many sensors that could be amiss if you all can give me some direction.

I am in the process of locating a shop that can diagnose what is currently amiss. That is incredibly difficult in our part of the Philippines and I would appreciate any help you can give.


Maintenance Schedule and other issues:

The vehicle has had regular maintenance with following driver’s manual and recommendation for belts/fluids etc. We have had more frequent oil changes than suggested by ISUZU thinking it may help the problems with the car.

The vehicle has always had a lot of black smoke production especially when we would have to accelerate to overcome the recurrent with the recurrent CEL problem above. Now after the car has begun surging and reving/accelerating without pressing accelerator the black smoke is much more.

Thank you all in advance once again. I know we bought a headache years ago but buying another vehicle really isn't possible right now.
bionemesis
I'm only here for the information
 
Posts: 2
Joined: Mon Feb 08, 2021 11:11 pm
Location: CDO Philippines
Age: 38
Country: Philippines
City: CDO
Vehicle: 2003 Isuzu Trooper 3.0 DOSC c sunroof and 4XJ1 engine

Re: Trooper 3.0 DOHC Diesel VJX1 problems with surging/dirty

Postby geeves » Tue Feb 09, 2021 9:37 am

Oil and diesel mixing in a 4jx1 first suspect is always the injectors but head gasket also possible
Sanding your knuckles before starting work can help. That way you cant skin them
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geeves
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Posts: 8962
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2013 Subaru XV

Re: Trooper 3.0 DOHC Diesel VJX1 problems with surging/dirty

Postby bionemesis » Tue Feb 09, 2021 9:21 pm

Thanks geeves. What do you think about the number two problem? It's continued for about 40,000 KM with no mechanic able to figure it out. A recent mechanic thought it was maybe from the bad injectors not being in sync with the transmission and he thought that the injectors when fixed could then be recalibrated to the transmission to alleviate that problem.

Today I found out that yes the four injector sleeves and O rings were bad with extensive mixing of oil and diesel, as well as at least one injector full of water and diesel. Also the mechanic found out that the new fuel pump wasn't functioning properly and contributing to intermittent loss of vacuum and introduction of air. I"m thankful for his help. The second problem continues though.
bionemesis
I'm only here for the information
 
Posts: 2
Joined: Mon Feb 08, 2021 11:11 pm
Location: CDO Philippines
Age: 38
Country: Philippines
City: CDO
Vehicle: 2003 Isuzu Trooper 3.0 DOSC c sunroof and 4XJ1 engine

Re: Trooper 3.0 DOHC Diesel VJX1 problems with surging/dirty

Postby geeves » Wed Feb 10, 2021 10:59 am

Diesel contaminated oil can ruin an engine Scored bores and bearings
Sanding your knuckles before starting work can help. That way you cant skin them
User avatar
geeves
Site Admin
 
Posts: 8962
Joined: Sun May 10, 2009 1:36 pm
Location: Rangiora
Age: 63
Country: NZ
City: Rangiora
Vehicle: 94 bighorn 4jg2
2013 Subaru XV


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