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Bogging at low rpms


Cory74700
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I'm running an '88 pathfinder VG30i motor, when I take off, if I shift to second too soon when I'm getting on the gas pedal it bogs out like sputtering while super slowly upping the rpms till I hit 3,000 then I get a quick torquey jump of power, I mean I can just shift to the next gear at 3,500rpms, to 5,500rpms and this never happens, just around 1,500-2,000rpms, any clue as to what's going on?? I was told it had to do with my EGR valve but that seems senseless, would my plan to convert to a carburetor fix this issue?? But just need a main answer of what's happening and how do I stop it from happening?? Thanks for any help in advance.

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You can switch to a carb and there's even a member here (Mr.510) that sells adapters to attach Holley carbs. It would make everything simpler but the fuel economy might go down a little. Mine used to bog like that when I had a bad oxygen sensor. Try disconnecting that and see what happens. Make sure you also don't have an exhaust leak.

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Tungsten I do know that I have an exhaust leak as I can hear my valves ticking loudly at high tons and I was underneath it today and I could jiggle my muffler away from the cat about 1/4 inch I think I can just tighten my u-bolt to fix that though but I believe my o2 sensor is working because I passed smog with flying colors earlier this year and the problem has existed since I git it

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Those don't look like the codes from an 88, more like a 98. The codes using the red and green blinking lights on the ECU should be 2 digits.

 

55 (5 red, 5 green flashes) would indicate all ok

 

The codes you posted are OBD2 codes which didn't start being used until 1996

Edited by ahardb0dy
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I used a portable obd2 scanner with an attachment for obd1 with programming that's supposedly able to go back to 1975 year cars and newer, I'm not sure how to get the codes using the lights if you explained it I can try that one tomorrow afternoon and post back with results.

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Slide the pass. seat forward, remove the cover on the ECU if it has one

locate the switch, should be on the rear of the ECU

locate the little window with red and green LED's under the clear plastic

Turn ignition switch on

move the switch on the ECU to the "on" position

when the red and green LED's flash together 3 times shut the switch off ( this puts the ECU in the self diagnostic mode)

record the number of flashes of the red and the green LED

 

for example 5 red flashes, 5 green flashes means all ok

 

after each color flashes, let it flash again, if you get the same code than that would be the only code, if you get a different number of flashes than that would be a second code, keep looking at the flashes until they repeat than you are done

 

I don't have a FSM for the 88 but these are the codes from the 1989 FSM:

 

11 - Crank Angle Sensor circuit

12 - Air Flow Meter

13 - Cylinder head/Water temperature Sensor circuit

21 - Ignition signal missing in primary coil

31 - ECU - (E.C.C.S. Control unit)

32 - E.G.R circuit (California only)

33 - Exhaust gas sensor circuit

35 - Exhaust gas temparature sensor circuit (California only)

43 - Throttle Sensor circuit

45 - Injector Leak (California only)

51 - Injector (VG30i model only)

55 - No malfunctions

Edited by ahardb0dy
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I had the same problem with my 94 auto. When RPM's would drop when shifting to overdrive on the freeway it would bog. What fixed mine was replacing the coolant temp sensor or the engine temp sensor? Its a gold one that looks like a spart plug. It just under the upper radiator hose on my 94.

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Well I was in quite a bind today trying to get some new tires and didn't have time to get home and check through the ecu with the flashing lights so ill have to do it tomorrow, then if I get the o2 sensor One ill try to tighten up my exhaust around the exit of my catalytic converter and then do it again and see if they still do the same, if I can ill try and get a video because all this blinking light stuff is new to me and maybe one of you guys can decipher it for me instead of me scratching my head on it. just a double check the red should flash first then green right??

 

Thank you to everyone who has added their input to help me out so far, and happy New years, ill be talking to you all in the 2013 year.

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So i decided to do the video tonight, and it came up 5 red flashes, 5 green flashes, i let it cycle through twice to see if it changed or not. im still puzzled though, ill do a video tomorrow while driving, don't worry ill do it in an empty parking lot to ensure i don't endanger other drivers while driving with my phone in my hand to record the video, and ill do it a few times to make sure i get a good sound quality for you guys, the sound on this video sucked unless your volume is up high. but heres the ECU go at it. came up with no malfunctions.

 

Edited by Cory74700
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I used a portable obd2 scanner with an attachment for obd1 with programming that's supposedly able to go back to 1975 year cars and newer, I'm not sure how to get the codes using the lights if you explained it I can try that one tomorrow afternoon and post back with results.

Just curious what brand and model of OBD2 scanner you used? Cheers

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