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Old 03-01-2007, 06:42 PM   #1
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Default Rough running

I just did my intake gaskets yesterday, and now my car runs rough. Seems like a crossed plug wire, but it'* not. However, here is where I believe my problem lies. The EGR valve tube going from the exhaust to the valve base, is busted. It'* not hooked up but only leaking exhaust. The car idles about 1500, anything lower it wants to stall, often times it will. And as soon as TCC lockup comes in it shakes noticeably till 60 [never did this before, guaranteed a power related issue, because if TCC is off it doesn't shake]. I'm going to get a new EGR base and tube tomorrow at the yard, but I want to know if that'* totally unrelated.

Also, hot and cold don't make a difference, no SES light except for QDM, which is totally unrelated, that has been there for-ever. Loss of power as well... but she'll hit 5k np, just takes a bit longer using I would assume loads of fuel.
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Old 03-01-2007, 11:39 PM   #2
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fix the EGR. having it broken like that will make your car idle that high. My friend is having the same problem right now, we are just waiting for all the new gaskets to come in. his EGR tube is not broken but has a bad gasket and bad intake gaskets sometimes it idles at 2500! Also it eats fuel like crazy right now 1/2 tank in 2 days EASY
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Old 03-01-2007, 11:44 PM   #3
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Your EGR wants to be injecting exhaust gasses with very little combustible oxygen. Because the pipe is broken, it'* injecting combustible air, causing you to run lean. Too much air, not enough fuel.

That'* at least PART of the problem.
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Old 03-02-2007, 11:26 AM   #4
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Alright, I'll get on it. I hooked up the tube, but it'* definitely broken, and i'm sure isn't sealing properly. Would it be any better if I unplugged the EGR for the time being?
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Old 03-02-2007, 02:05 PM   #5
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Default rough

Also check if you may have reversed a few of the injector connectors when removing the intake. I think JR did this once and he even drove the car a while before finding it. LoL....
Maybe he will chime in here.
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Old 03-02-2007, 04:40 PM   #6
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He'* busy trying not to do the same thing again. UIM and LIM are off the car right now.
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Old 03-03-2007, 04:51 PM   #7
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Naw, not it, because I pulled it off at the injector harness not at the individual harness.

I've noticed when it idles, which really makes me think it'* all EGR; it will drop idle from 15 to 10 real quick, def not IAC quick. Then it'll come back up. And even faster than vacuum leak bad idle... it really seems like EGR valve opening, too far RPM drop, or the ECU senses it'* not smooth then kicks it back up.. and it'll keep trying it maybe 5x/min or so. But car in gear it'll stay down that low until it feels like it, foot on gas or not. If timed perfect, it once took almost 5sec before it recovered from a 1k idle w/ load to enough power to propel the car.

Fuel economy sucks too... about 12mpg... and that'* gramma driving for sure.
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Old 03-03-2007, 05:38 PM   #8
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Ok, so go fix the EGR and let us know.
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