1998 Isuzu Amigo S 3.2 P0442 DTC

[Debi23]

Hi

I had incurred the P0442 DTC before replacing my fuel pump, I attributed the code to a pinched gas cap line, as it went off after I corrected the issue. P0442 reoccurred after I replaced my fuel pump. My question is, would P0452, P463 and P0442 receive PCM commands via drivers side inner fender well wiring harness H4? I believe P0463 sensor circuit high input is caused by a compatibility issue (1998-1999) relating to my new fuel pump, voltage higher in new fuel pumps which will require SPS programming, I will have that accomplished in a day or two.

Thank you!!!

Debi23

[Buster28]

Hi

I had incurred the P0442 DTC before replacing my fuel pump, I attributed the code to a pinched gas cap line, as it went off after I corrected the issue. P0442 reoccurred after I replaced my fuel pump. My question is, would P0452, P463 and P0442 receive PCM commands via drivers side inner fender well wiring harness H4? I believe P0463 sensor circuit high input is caused by a compatibility issue (1998-1999) relating to my new fuel pump, voltage higher in new fuel pumps which will require SPS programming, I will have that accomplished in a day or two.

Thank you!!!

Debi23

DTC P0442 is a failure of the Vacuum Decay Test (VDT). The VDT checks for small leaks to atmosphere in the EVAP system pipes, hoses and hardware. The decay rate is determined by measuring the change in the fuel tank pressure ("Vacuum") as measured by the Fuel Tank Pressure Sensor over a period of time. If the decay rate is more than a calibrated value, another VDT will be initiated. If vacuum decay is still more than a calibrated value, a malfunction is indicated by setting DTC P0442.


Start troubleshooting by making sure the gas cap is the correct one and is sealing properly.

[Debi23]

Hello

The DTC P0442 code came back, I checked the fuel cap, car is running great. Do you think harness connector H4 is the culprit?

Thanks,

Debi23

[Buster28]

Your Tech II should be able to read/monitor the signal produced by the Fuel Tank Vapor Pressure Sensor. What is the value with the gas cap removed and the engine running at idle with the truck stationary?

[Debi23]

Hello,

I didn’t get the test done, the Isuzu manual said to connect J41413 to the EVAP service port, sounds like I need a evaporative emissions system tester and cap & plug kit these didn’t come with my Tech2.

Debi23

[Buster28]

The PCM is using the Fuel Tank Pressure Sensor signal to pass/fail the EVAP leak test so this parameter should be available to be retrieved by the TechII. I think the mode 22 PID number is 1687. I have a Note in my Autoenginuity scan tool file indicating I read this parameter on my 02 Rodeo Sport and the pressure was 1.47 Vdc and the FSM indicated the expected value was 1.51 Vdc at sea level. I am 200 ft above sea level.

[Debi23]

Hi

Sorry, I’m stuck on this one, I think in order to use the Tech II for the tank pressurization task I need another tool, the evap pressure purge cart j41413. I guess there is a port to connect to somewhere on the evap system. I think using the Tech II for this task is above my skill set as well, so we are going to have to dumb it down a bit. The only DTC is P0442, small leak. A while back I pinched the fuel cap cord maybe I damaged the fuel cap gasket.

Thanks,

Debi23

Found this on the internet might help me get up to speed

https://www.atechtraining.com/where-the ... s-learning

[Buster28]

Are you familiar with OBDII mode 22 commands?

[Debi23]

Hello

I know how to activate relays and sensors as part of the testing regime.

Thanks,

Debi23

[Buster28]

Interesting old discussion on using Mode 22 to get data from the PCM:
https://www.planetisuzoo.com/viewtopic. ... le=desktop

[Debi23]

Hi

Interesting discussion, very technical. I’m buying a new gas cap today, if that doesn’t work maybe I’ll do a smoke test if I can find the EVAP access port. P0442 seemed to appear after I pinched the fuel cap cord, maybe the seal was damaged. Car still running great, MPG at near 18, mix of highway and town driving. A lot better than the 14 MPG I was getting when I first posted on Planet Isuzu some months ago. I’ll keep you posted!

I also thought you might be interested that the Isuzu TIS2000 programming station that I bought is back again for sale on eBay, obviously the seller is cloning the system, so goes the claim “last one”. Oh well, I accomplished the fuel sending unit programming on my PCM and the computer will be helpful when I attempt to work on my ABS DTC.

Lastly, is the Painless 60550 GM Gen III Bench Top Programming Pigtail compatible with the later model Isuzu’s like yours? Someone with a 2002 wants their PCM re-programmed. I think the 1998-1999 Amigo’s and Rodeo’s shared the same PCM, then the PCM changed to the 3rd generation from 2000-2008.

https://www.amazon.com/dp/B005AU9880/re ... UTF8&psc=1

Thanks,

Debi23