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car lags and idle gets really low

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Old 02-12-12, 12:11 AM
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guku0701
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Default car lags and idle gets really low

i had this problem for a while now but its starting to bother me.car runs ok when engine is cold.atleast the first few rpms as i dnt rev hard when engine is cold.after i accelerate when its warm it does not wanna go.kinda like bogs down.i have changed the maf but theres no difference.anyone got any ideas where to start?
Old 02-12-12, 12:13 AM
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guku0701
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Originally Posted by guku0701
i had this problem for a while now but its starting to bother me.car runs ok when engine is cold.atleast the first few rpms as i dnt rev hard when engine is cold.after i accelerate when its warm it does not wanna go.kinda like bogs down.i have changed the maf but theres no difference.anyone got any ideas where to start?
if i keep the accelerator real smooth and slow itll give out smooth acceleration but when ever i try to floor it or give it a little more gas it will slow down and no power at all.its a 92 sc400 with 188k miles.
Old 02-12-12, 04:26 PM
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guku0701
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anyone? any help will be greatly appreciated
Old 02-12-12, 05:08 PM
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xboostx
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could be lack of fuel, possibly running lean
Old 02-12-12, 05:33 PM
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guku0701
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it does smell a lot like fuel when i start it..could this be a fuel pump issue?
thanks for reply
Old 02-12-12, 05:50 PM
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Tabaka
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I sort of experienced the same thing this weekend. Check out my thread called "Does this car hate me" :lol:

Pretty sure it's the fuel pump or fuel pump ECU. Get a fuel pressure test done and go from there.
Old 02-12-12, 05:56 PM
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Kymber317
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It could be the fuel pump ECU going out. Here is a link on how to do it: https://www.clublexus.com/forums/per...tures-faq.html
Old 02-12-12, 08:44 PM
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Mine does this as well but its a different setup entirely. It also runs very rich (based on wideband and fuel odor) and has stalled out one time idling. I've been told it is the IACV. Fuel pressure is stable. Goes away within a few minutes of warming up.
Old 02-12-12, 09:45 PM
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guku0701
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Originally Posted by Tabaka
I sort of experienced the same thing this weekend. Check out my thread called "Does this car hate me" :lol:

Pretty sure it's the fuel pump or fuel pump ECU. Get a fuel pressure test done and go from there.
i just checked out your thread..its kinda exactly what my problem is too..did you find a solution yet?i will be taking it to the mechanic tomorow to get the fuel pressure checked out and kinda interested to do the 12v mod.let me know what your solution is.
thanks
Old 02-12-12, 09:47 PM
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guku0701
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Originally Posted by Kymber317
It could be the fuel pump ECU going out. Here is a link on how to do it: https://www.clublexus.com/forums/per...tures-faq.html
i will defenitely try this tomorow after i pay a visit to my mechanic.or do you think i should start with the mod first?
Old 02-12-12, 09:47 PM
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guku0701
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Originally Posted by INTIMAZY
Mine does this as well but its a different setup entirely. It also runs very rich (based on wideband and fuel odor) and has stalled out one time idling. I've been told it is the IACV. Fuel pressure is stable. Goes away within a few minutes of warming up.
hmm wierd thing is it gets worse when its warmed up.ill keep this in mind too.
thanks
Old 02-12-12, 09:54 PM
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k7q
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plugs and wires? my car was sputtering and lacking power, but after i changed my wires it felt like a v8 again. i didnt change the plugs because it was iridium.
Old 02-12-12, 10:24 PM
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Originally Posted by k7q
plugs and wires? my car was sputtering and lacking power, but after i changed my wires it felt like a v8 again. i didnt change the plugs because it was iridium.
is there a way to check the wires?
Old 02-13-12, 02:12 PM
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guku0701
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ok so i just did the 12v mod but dont see any change at all.any ideas before i send it for diagnostics tomorow?
Old 02-19-12, 10:47 AM
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Originally Posted by guku0701
is there a way to check the wires?
hmm theres a special tool for it. but a ghetto method is to put a screw driver in the wires, put it near a ground to see if it sparks? got to have someone crack it though. i did that when i was messing around with hondas though.
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