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Technician Chris
Technician Chris, Technician
Category: Car
Satisfied Customers: 425
Experience:  I am a certified ASE Master Technician with L1 Advanced Diagnostic Specialist and over 15 years experience.
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Isuzu Rodeo: I have a 2002 rodeo with 3.2 V6 , having trouble

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I have a 2002 rodeo with 3.2 V6 , having trouble with my engine running smooth on acceleration sometimes it will accelerate perfectly like this not miss and is getting everything it needs and running perfect and sometimes I step on the gas and it feels like its starving for fuel . then all the sudden if something will click and I will take off and run perfect . if it had a carburetor I would rebuild it cuz it acts like a carburetor accelerator pump is not working . like I say sometimes it acts up really bad and I have to really kick it down shift gears , is it automatic, in order for to run and sometimes while it is acting up it will all of a sudden click and it will run perfectly fine for a while .next time I start it might run perfect then down the road act up then clear up. I have gotten a few codes 1153 at 1133 out of it and 300 multiple misfire. I've also seen 152 code. Already put new plugs the book calls for.changed bank 2 upstream 02 sensor. Checked all vacuum lines and checked for vacuum leaks. Scott

P1153 - HO2S Insufficient Switching Bank 2 Sensor 1


P1133 - HO2S Insufficient Switching Bank 1 Sensor 1


P0300 - Engine Misfire Detected


P0152 - HO2S Circuit HIGH Voltage Bank 2 Sensor 1


P0401 - Exhaust Gas Recirculation (EGR) Flow Insufficient Detected


- There are only 2 parts that could cause off all these codes, and the rough running issue you described. A faulty PCM is always a possibility, but is uncommon, and would be the last resort. More common is the mass air flow sensor. Even though you don't have any actual mass air flow sensor codes, does not mean it is functioning properly. The codes would only indicate electrical circuit faults, but if the sensor is not reading correct, it may not give any such codes. Or, it could just be contaminated and IS functioning properly, but is giving the PCM false readings. I would start by cleaning the mass air flow sensor. You must use proper cleaner to do this as this part is very sensitive. Do NOT use brake cleaner on this. You can buy either special mass air flow sensor cleaner or electrical component cleaner at any auto parts store for around $6 - $10. Just remove the sensor and spray the heck out of it from all angles, let it dry, and reinstall it. I would also suggest removing the battery's negative post to reset computer back to base settings. I have "repaired" many vehicles over the years that have had the same symptoms as yours with just a sensor cleaning. If nothing changes, I would recommend to replace the sensor. Part number:(NNN) NNN-NNNN Please clean it 1st, test drive for a day or so, and let me know the results.

Customer: replied 3 years ago.

I will try today and get back to you.


Sounds good, let me know, thanks.
Customer: replied 3 years ago.

Well I tried to clean the ma's airflow, didn't worked. I replaced it and it worked and didn't. It took almost all hesitation away except when at idle , it will idle about 8 to 9 hundred rpms and drop down to 5 hundred and almost stall, and then like someone switched a switch, it will jump right back to 8 to 9 hundred rpms. I'll be going about 45 mph, engine will be around 2000 rpms and the engine will start jumping from 2000 to 2200 rpms and back and forth. Can't tell if its the engine or shifting between drive and over drive. I did take off neg battery terminal and reset the computer after installing the new mass sensor. I ran it several times , clearing codes each time. Right now it has trouble code 0152, 1133, and 300. Pending codes are 300, 1133, and 1153. I'm stumped, crank sensor?. Scott.

Outwell it's now Saturday morning I took the car for another ride there is still some hesitation and then all of a sudden it will kick in like somebody flipped a light switch . not as bad as it was before I change the mass airflow sensor . also there's now that hesitation I said that happened yesterday between 2000 and 2200 rpm that happened today started surging . but it was only between 17 and 1900 p.m. The engine is just surging .I'm not sure what else to tell you but its still the same . .the surging is happening when I'm not a seller rating or decelerating just Hollin the gas pedal steady The surging happens when im holding the gas steady, not accelerating or decellorstingthingq

P0152 HO2S Circuit HIGH Voltage Bank 2 Sensor 1


P1133 HO2S Insufficient Switching Bank 1 Sensor 1


P0300 Engine Misfire Detected


- Double check for any vacuum leaks. That is the most common possibility of the surge. If no leaks are found, I would clean out the throttle body, and perform an upper induction service. A shop can do this for about $80 - $120. That will get out all of the carbon build up that may cause a rough running issue. If that does not take care of it, then next step would be to test the throttle position sensor, and replace if needed. This is relative easy on this vehicle if you have a digital multi meter.


TP sensor output voltage at closed throttle:

  • The voltage should be TP1 about 0.4V , TP2 about 4.6V and TP3 about 4.6V
  • If the reading is abnormal value, check the throttle shaft to see if it is binding.

The throttle position (TP) sensor is a potentiometer connected to the throttle shaft on the throttle body. The PCM monitors the voltage on the signal line and calculates throttle position. As the throttle valve angle is changed (accelerator pedal moved), the TP sensor signal also changes. At a closed throttle position, the output of the TP1 sensor is low. As the throttle valve opens, the output increases so that at wide open throttle (WOT), the output voltage should be above 92% (Tech 2 Display).

The PCM calculates fuel delivery based on throttle valve angle (driver demand). A broken or loose TP sensor may cause intermittent bursts of fuel from an injector and unstable idle because the PCM thinks the throttle is moving.


- let me know if you need further assistance - we WILL find the source of the issue!

Customer: replied 3 years ago.

Ican't respond yet to you last things you told me to try because I can't get to it till tomorrow I can't write you and tell I tried what you said to try next I don't know if it's going to work I'm not sure we still getting I'm still getting cold after driving it today

Just let me know when you can. Keep in mind, this thread is on a time limit. It is scheduled to end in 3 days. You may extend that time by rating my answer. After giving me a rating, you may continue to post questions / responses to keep the thread open without having to pay again, but if no rating is given, it will time out.
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Customer: replied 3 years ago.

this vehicle is going to drive me nuts.yesterday driving yet I got a free hundred code 1133 1153 and 152. I have bought a spare vehicle for spare parts so I had an extra throttle body and throttle position sensor and I put them on and talking for a test drive what we got was random of 300 ,1153, 1133 and 152. the vehicle seem to run great far as I could feel no more surging nice n smooth no hesitation, it drop low rpms one when we first started to take off, but didn't do it again. Cleared codes went for another ride and all I got was 132 code. No other codes. Yesterday

some point got a 131 and a 1751.

P0131 HO2S Circuit Low Voltage Bank 1 Sensor 1


P0132 HO2S Circuit High Voltage Bank 1 Sensor 1


- I don't have a listing for P1751.


- I know you have already changed the B2S1 O2 sensor. Before replacing the B1S1, check the connections. At the sensor, the electrical connector, and at the PCM. Corrosion build up could also cause these issues. If nothing is found, stick a new B1S1 sensor in there and see what happens. See the wire diagram and diag chart below:




Circuit Description
The powertrain control module (PCM) supplies a bias voltage of about 450 mV between the heated oxygen sensor (HO2S) signal and low circuits. When measured with a 10 megaohm digital voltmeter, this may display as low as 320 mV . The oxygen sensor varies the voltage within a range of about 1000 mV when exhaust is rich, down through about 10 mV when exhaust is lean. The PCM constantly monitors the HO2S signal during "closed loop" operation and compensates for a rich or lean condition by decreasing or increasing injector pulse width as necessary. If the Bank 1 HO2S 1 voltage remains excessively high for an extended period of time, DTC P0132 will be set.

Conditions for Setting the DTC

  • No related DTCs.
  • Engine coolant temperature is above 60 °C (140 °F)
  • "Closed loop" commanded air/fuel ratio is between 14.5 and 14.8.
  • Bank 1 HO2S 1 signal voltage remains above 952 mV during normal "closed loop" operation for a total of 77 seconds over a 90-second period. OR
  • Bank 1 HO2S 1 signal voltage remains above 500 mV during "deceleration fuel cutoff mode" operation for 3 seconds .

Action Taken When the DTC Sets

  • The PCM will ON the MIL after second trip with detected fault.
  • The PCM will store conditions which were present when the DTC was set as Freeze Frame and in the Failure Records data.
  • "Open loop" fuel control will be in effect.

Conditions for Clearing the MIL/DTC

  • The PCM will turn the MIL "OFF" on the third consecutive trip cycle during which the diagnostic has been run and the fault condition is no longer present.
  • A history DTC P0132 will clear after 40 consecutive warm-up cycles have occurred without a fault.
  • DTC P0132 can be cleared by using the Tech 2 "Clear Info" function or by disconnecting the PCM battery feed.

Diagnostic Aids
Check the following items:

  • Fuel pressure - The system will go rich if pressure is too high. The PCM can compensate for some increase. However, if fuel pressure is too high, a DTC P0132 may be set. Refer to Fuel System Diagnosis.
  • Perform "Injector Balance Test" - Refer to Fuel System Diagnosis.
  • Check the EVAP canister for fuel saturation - If full of fuel, check canister control and hoses. Refer to Evaporative (EVAP) Emission Control System .
  • MAF sensor -The system can go rich if MAF sensor signal indicates an engine airflow measurement that is not correct. Disconnect the MAF sensor to see it the rich condition is corrected. If so, replace the MAF sensor.
  • Check for a leak in the fuel pressure regulator diaphragm by checking the vacuum line to the regulator for the presence of fuel. There should be no fuel in the vacuum line.
  • An intermittent TP sensor output will cause the system to go rich due to a false indication of the engine acceleration.
  • Shorted Heated Oxygen Sensor (HO2S) -If the HO2S is internally shorted, the HO2S voltage displayed on the Tech 2 will be over 1 volt . Try disconnecting the affected HO2S with the key "ON," engine "OFF." If the displayed HO2S voltage changes from over 1000 mV to around 450 mV , replace the HO2S. Silicon contamination of the HO2S can also cause a high HO2S voltage to be indicated. This condition is indicated by a powdery deposit on the portion of the HO2S exposed to the exhaust stream. If contamination is noticed, replace the affected HO2S.
  • Open HO2S Signal Circuit or Faulty HO2S-A poor connection or open in the HO2S signal circuit can cause the DTC to set during deceleration fuel mode. An HO2S which is faulty and not allowing a full voltage swing between the rich and lean thresholds can also cause this condition. Operate the vehicle by monitoring the HO2S voltage with a Tech 2. If the HO2S voltage is limited within a range between 300 mV to 600 mV , check the HO2S signal circuit wiring and associated terminal conditions.
  • If none of the above conditions are present, replace the affected HO2S.





Customer: replied 3 years ago.

I was going to ask , when I scan , sometimes mil is on and some times off. Does that help?.

That does not make any difference. When you replaced the throttle body, did you disconnect the battery for at least 5 mins? This will ensure all values are reset to factory specs.
Customer: replied 3 years ago.

No will do.

Customer: replied 3 years ago.

I understand what you're telling me on how to test each sensor.something is making these sensors give codes. I don't think the sensors are bad, but there is something going on making the sensors give me the codes. i've changed the mass air flow, put on new throttle body with a different TCP on it ,we replace oxygen sensor tha still gives the 152 code . does that mean it is cam sensor ,crank sensor , bad fuel injectors . after I reset the battery , I took it for a ride, it was cold, before it was completely warmed up, I would accelerate it I got a 300 code. Drove it about 7 miles 8 miles and also got a 152 , they were pending bcodes not trouble codes. I ate supper I cleared the codes, drove about

15 miles no codes what so ever ran app solutely perfect, had a coffee and drove home when I was driving home check engine light came on

again 300 code 152 something's acting up , but not all the time. I pulled all the coils and checked them. New plugs, ngk's. On the way home when it acted up again, it fell on its face, then all of a sudden , like a switch, refer up and ran smooth and really accelerated. Lost on what to do next.

I do believe the reason the engine suddenly bogs down is because it switches back to "open loop" after detecting the conditions to set a P0152 code. I would really like to see some freeze frame data when the code is set. You may have an intermittent leaking injector or very subtle vacuum leak. I would also like to do a fuel injector balance test and fuel pump pressure test to determine output of the pump and each injector. I really hate to say this, but you may have to take it to the dealer and pay for diag. We have covered all the common possible problems, and will need deeper diagnostics tests. If you do take it to a dealer, I would really like to know the outcome. Please let me review the estimate before having them proceed w/ a repair. If you don't have an Isuzu dealer near by, you can take it to a Honda dealer being the engine was built by Honda.

Customer: replied 3 years ago.

Thank you . I'll let you know.

sounds good