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Car Bogs unless MAF is unplugged... Help

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Old 06-07-09, 08:48 PM
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RedPhoenix
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Default Car Bogs unless MAF is unplugged... Help

I have been recently getting this weird bogging issue. Car feels like its lacking a lot of power... bogs in any gear etc...

While I was at a light, I thought of the idea... unplug the MAF and see what happens. So I did. Then proceeded to drive the car like it was meant to be.

The car ripped... Felt like it had gained a lot of power and there was no bogging anymore. But it is now pig rich. However I do NOT have a CEL with the MAF unplugged... weird.

So what do you concur? Is it the MAF? What else could it be? Why is there no CEL and the car doesnt really have a hard time idling (fluctuations between 600-800rpms).

So now I am forced to drive it without the MAF plugged in because the car bogs with it plugged in.
Old 06-07-09, 09:48 PM
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topdog849
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it sounds like you already found your problem, try using some maf senser cleaner from advance or replace it.
Old 06-07-09, 11:42 PM
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KrazeMatik
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does your o/d flashes?
Old 06-08-09, 12:34 AM
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JDMmuscle
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Take off your driver side wheel and look up into the fender liner, This happened to me as well.... turns out i had stripped a bunch of wires... One of them was my maf wire.


Technically your car shouldnt run with the maf unpluged, so there should be a wire issue some where. Try cleaning your Maf first tho
Old 06-08-09, 01:25 AM
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sc-driver
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sounds like it went bad, or needs a really good cleaning.

I've noticed that cars with Karman maf's (92-95) will still run if you disconnect the maf But if you do the same on a 96+ with a hotwire maf, the car won't even start.

like JDMmuscle said, clean it first and see what happens.
Old 06-08-09, 04:58 AM
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RedPhoenix
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Originally Posted by KrazeMatik
does your o/d flashes?
Only because of the manual transmission, not MAF. Why?

Originally Posted by JDMmuscle
Take off your driver side wheel and look up into the fender liner, This happened to me as well.... turns out i had stripped a bunch of wires... One of them was my maf wire.


Technically your car shouldnt run with the maf unpluged, so there should be a wire issue some where. Try cleaning your Maf first tho

The wires have not been touched at all (which is good news lol).




Looks like I will try and borrow a friends MAF.
Old 06-09-09, 06:52 AM
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RedPhoenix
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Another MAF did not fix the problem. Whats next?
Old 06-09-09, 11:13 AM
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SC30096
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reset the ecu? have you added any aftermaket electrical components?
Old 06-09-09, 12:23 PM
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sc-driver
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With the maf plugged in, does your car feel like it drives stronger or weaker on very cold start ups? (before reaching normal operating temperature)

This is starting to remind me of the problem Och had with his LS400.
https://www.clublexus.com/forums/ls4...-question.html

Och could never really find a solution, but we narrowed it down to it possibly being a bad ecu. If you can find somebody around, try using their ecu and see if it helps.
Old 06-09-09, 01:08 PM
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RedPhoenix
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Very similar... But it doesnt feel great when its cold either. But it feels better.

I will try ECU.
Old 06-09-09, 01:15 PM
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If you have an intake system. That would be your culprit instead of the MAF. You would need to get an ECU to accompany your PCM so it can compensate for the Air and Fuel mixture. Many people install the intake and fail to have the ECU programed will cause lost in performance and driveability issue. Hope that helps.
Old 06-09-09, 01:27 PM
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RedPhoenix
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stock intake. I hate aftermarket ones, they are garbage and do nothing.

Engine is untouched minus EGR delete which was done months before this issue and the obvious 5sp swap.
Old 06-09-09, 02:31 PM
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SHOLEXMAN
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Matt did you ever borrow another ecu from anybody elses car? You could use my brothers if you want since mine is a 95. I think the ECU is bad cause that is weird and it should die once it is unplugged.
Old 07-18-09, 03:09 PM
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Pre 95 SC400 can operate with MAF unplugged! Just tried on my car to confirm.
Old 07-21-09, 09:32 PM
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soaringsc3
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have a very similar problem with bogging and mass power loss but I was told that it could be time to replace the spark plugs?
help would be fantastic its my dd


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