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4jh1 power up help.

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4jh1 power up help.

Postby dat610 » Wed Aug 26, 2020 2:02 am

Hi all, I'm new to this forum and pretty new to rodeos, I recently bought one (2005 4x4 Holden Rodeo 4jh1 tc) as I couldn't afford to fuel my Patrol for daily/work use.

When I first purchased my Rodeo it was seriously down on power, I have since removed the cat (other old one was cracked and partially blocked) I fitted a aftermarket dump pipe and mandrel bent 2 1/2" exhaust, blanked the egr valve, changed the viscous hub (which was dragging) and done a full service, i also checked inside the inlet manifold and intake pipework including the intercooler for buildup and excessive oil but that was ok.
I also removed the turbo and had it inspected and it is in good condition.
The previous owner had the injectors replaced 40 000km ago.
All of this has helped a bit for power but I'm not convinced its running at normal power levels yet.
Besides all this it runs excellent.

I was speaking to the spare parts guy at the local dealership and he said that the EVRV EGR solenoid could be the issue, I'm not sure exactly what it does but I'm assuming it controls the EGR valve which I have blanked off so I'm guessing changing this is going to be a waste of time, please correct me if I'm wrong.
He also mentioned about the map sensor and possibly a dirty maf sensor.
I dont know but its possible I'm expecting too much out of the 4jh1 but I'd like to rule out anything that could be slowing it down unnecessarily.

This also leads me to a few questions,

What are the most common faults that cause lack of power?
As I would like to make sure it's at least running how it should be before chasing more performance.

Are there any basic power ups that help improve performance?

What is involved in fitting a manual pump? Is there any information on doing this on the forum or anywhere else.

I'm sure a bit more fuel and boost would go along way to some better performance if everything is as it should be.

Any help or pointing in the right direction would be greatly appreciated.
Cheers
dat610
I'm only here for the information
 
Posts: 2
Joined: Wed Aug 26, 2020 1:03 am
Age: 36
Country: Australia
City: Adelaide
Vehicle: 2005 RA Rodeo 4x4 4jh1

Re: 4jh1 power up help.

Postby paulthepilot5 » Thu Aug 27, 2020 3:23 pm

dat610 wrote:Hi all, I'm new to this forum and pretty new to rodeos, I recently bought one (2005 4x4 Holden Rodeo 4jh1 tc) as I couldn't afford to fuel my Patrol for daily/work use.

When I first purchased my Rodeo it was seriously down on power, I have since removed the cat (other old one was cracked and partially blocked) I fitted a aftermarket dump pipe and mandrel bent 2 1/2" exhaust, blanked the egr valve, changed the viscous hub (which was dragging) and done a full service, i also checked inside the inlet manifold and intake pipework including the intercooler for buildup and excessive oil but that was ok.
I also removed the turbo and had it inspected and it is in good condition.
The previous owner had the injectors replaced 40 000km ago.
All of this has helped a bit for power but I'm not convinced its running at normal power levels yet.
Besides all this it runs excellent.

I was speaking to the spare parts guy at the local dealership and he said that the EVRV EGR solenoid could be the issue, I'm not sure exactly what it does but I'm assuming it controls the EGR valve which I have blanked off so I'm guessing changing this is going to be a waste of time, please correct me if I'm wrong.
He also mentioned about the map sensor and possibly a dirty maf sensor.
I dont know but its possible I'm expecting too much out of the 4jh1 but I'd like to rule out anything that could be slowing it down unnecessarily.

This also leads me to a few questions,

What are the most common faults that cause lack of power?
As I would like to make sure it's at least running how it should be before chasing more performance.

Are there any basic power ups that help improve performance?

What is involved in fitting a manual pump? Is there any information on doing this on the forum or anywhere else.

I'm sure a bit more fuel and boost would go along way to some better performance if everything is as it should be.

Any help or pointing in the right direction would be greatly appreciated.
Cheers


Most common failure on the 4JH1 is the injection pump. The electronic VP44 pump is problematic and very expensive to rebuild/replace. Also limited is it’s ability to be tuned, hence why there are a lot of people converting them to the mechanical VE pump
paulthepilot5
Isuzu Junior
 
Posts: 129
Joined: Thu Apr 05, 2018 8:56 pm
Age: 38
Country: Australia
City: Brisbane
Vehicle: 1995 Isuzu Rodeo 2.8d
Compound twin Turbo
12mm fuel Pump
+50 injectors
Water/meth injection

TF Rodeo ute 2WD short wheelbase
2.8 4JB1T
Inline injection pump conversion
+50 injectors
Borg Warner s200 turbo
300hp, 650nm

Re: 4jh1 power up help.

Postby dat610 » Sun Sep 06, 2020 6:33 pm

Thank you for your response,

Could you please point me in the right direction for information on converting to a Mechanical VE Pump.

Thanks
dat610
I'm only here for the information
 
Posts: 2
Joined: Wed Aug 26, 2020 1:03 am
Age: 36
Country: Australia
City: Adelaide
Vehicle: 2005 RA Rodeo 4x4 4jh1

Re: 4jh1 power up help.

Postby kostasskoun5060 » Sun Sep 06, 2020 6:49 pm

is smoke coming out of the car exhaust ???? up to how many revolutions does it rotate ??? the engine failure indicator lights up ???? send us a video to see the symptoms
kostasskoun5060
Isuzu Baby
 
Posts: 9
Joined: Wed Aug 26, 2020 5:48 am
Age: 18
Country: Australia
City: Bencubbin
Vehicle: ISUZU DMAX 2006 4JH1

Re: 4jh1 power up help.

Postby paulthepilot5 » Mon Jul 26, 2021 7:28 pm

dat610 wrote:Thank you for your response,

Could you please point me in the right direction for information on converting to a Mechanical VE Pump.

Thanks


I’ve started manufacturing adaptor kits to convert the 4JH1 to mechanical pumps
Look up “4J Performance Diesel Parts” on Facebook, or send me a message for info if you are still looking at doing the conversion.
paulthepilot5
Isuzu Junior
 
Posts: 129
Joined: Thu Apr 05, 2018 8:56 pm
Age: 38
Country: Australia
City: Brisbane
Vehicle: 1995 Isuzu Rodeo 2.8d
Compound twin Turbo
12mm fuel Pump
+50 injectors
Water/meth injection

TF Rodeo ute 2WD short wheelbase
2.8 4JB1T
Inline injection pump conversion
+50 injectors
Borg Warner s200 turbo
300hp, 650nm


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