First startup Bad Idleing... (240sx LS1)
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I started my LS1 for the first time, and it had this weird ups and downs in rpms which sounds like Air is leaking through somewhere... I installed the brake booster, I plugged up the EGR, and I installed the MAF sensor without an filter though... I didn't install new sparkplugs, and I didn't install the walboro fuel pump, its still on the stock 240sx fuel pump...
Anything else so we can actually find this bad idle problem?
Thanks
Anything else so we can actually find this bad idle problem?
Thanks
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sorry guys this video was taken when i was trying to unplug the maf.. but it is plugged now! and its the same ****! yes i will check for vacuum leakes! but wat else would do this prob?.. can it be any electric wiring fault??
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The first time I started my 5.3 I had the same problems for a little while even with everything hooked up right. You probably have headers and a custom air intake, it take running/driving the car to smooth everything out. PCM has to relearn fuel mapping and spark curves. good luck and check all grounds.
EGR behind throttle body needs plugin, and MAF not pluged in. Sounds like multiple problems, I'd double check everything, PCM tuned or stock?
EGR behind throttle body needs plugin, and MAF not pluged in. Sounds like multiple problems, I'd double check everything, PCM tuned or stock?
Last edited by 70Nova SS; 09-16-2008 at 11:48 AM.
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PCM has VATS removed only...
EGR is plugged but u can't see it, its blocked by the stock thing that was there already but with a metal piece welded in the hole...
All Grounds checked? Not really, I need to check that cause I don't trust my electrician, and u might ask why I go to him, he is the best here, but the best here is the shittiest in the states... so please no Judging lol...
I have another thread with the name, grounding my LS1 which is about this topic that I really have no knowledge at all in... (I guess it should be clear to me, but just to be extra sure, do u think grounding might cause such a problem?) because when I asked my electrician about grounding he said the ecu is already mounted on the cars body which gives it ground :S, and he only has one big ground going to the headers bolt from the battery, and from what I've heard those are not enough... which is why I think its the problem...
EGR is plugged but u can't see it, its blocked by the stock thing that was there already but with a metal piece welded in the hole...
All Grounds checked? Not really, I need to check that cause I don't trust my electrician, and u might ask why I go to him, he is the best here, but the best here is the shittiest in the states... so please no Judging lol...
I have another thread with the name, grounding my LS1 which is about this topic that I really have no knowledge at all in... (I guess it should be clear to me, but just to be extra sure, do u think grounding might cause such a problem?) because when I asked my electrician about grounding he said the ecu is already mounted on the cars body which gives it ground :S, and he only has one big ground going to the headers bolt from the battery, and from what I've heard those are not enough... which is why I think its the problem...
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reground it
and where is your IAT sensor?
what codes is the ECU throwing?
go replace your damn spark plugs too.
while the ecu will have to "relearn" everything, it will do it VERY quickly (within a few starts). whenever i reset my computer it takes a couple starts before it idles on its own but you are not hitting all 8 at idle.
and where is your IAT sensor?
what codes is the ECU throwing?
go replace your damn spark plugs too.
while the ecu will have to "relearn" everything, it will do it VERY quickly (within a few starts). whenever i reset my computer it takes a couple starts before it idles on its own but you are not hitting all 8 at idle.
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Ok I did install the IAT sensor, and a Full exhaust, im going to get new spark plugs, but whats the part number? NGK Code?
I heard a weird noise inside my engine, something as if someone through a small metal part inside the throttle body or head...
this sound never poped up b4, but this could be due to the loud sound from the open headers, but now that I have the full exhaust I can hear it (maybe) I don't know what it is... but its annoying, I shut down the engine immediatly... tomorow we're going to check whether theres something inside...
or whats going on...
I heard a weird noise inside my engine, something as if someone through a small metal part inside the throttle body or head...
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![Sad](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_sad.gif)
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ok... I found out that my MAP sensor is broken, I called my friends in Saudi Arabia to send me one, cause we have non in Lebanon... and I also found out that the Cam Sensor was unplugged also...
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OK guys UPDAAATE: lol
but not everything is good news... here is it...
I installed the fuel pump, I installed new sparkplugs, I installed the cam sensor and the connector... I also bought a New MAP sensor and installed it...
So we turned the car on, and I hear this weird noise as if a metal piece is stuck in the head or block somewhere... but its not something constint the sound disappears then comes back making it very hard to distinguish whats wrong with it... :S
Anyone?
but not everything is good news... here is it...
I installed the fuel pump, I installed new sparkplugs, I installed the cam sensor and the connector... I also bought a New MAP sensor and installed it...
So we turned the car on, and I hear this weird noise as if a metal piece is stuck in the head or block somewhere... but its not something constint the sound disappears then comes back making it very hard to distinguish whats wrong with it... :S
Anyone?