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Discussion Starter · #1 ·
My speed3 has 7500 miles on it. Five days ago i installed a cobb sri and everything seemed normal (minus the new sound of air being sucked into the engine and factory bov comming to life). Then 2 days ago i had my first oil change and switched to full synthetic 5w-30 Kendall GT-1.

Today i noticed that my idle is up a little past 1000 rpm. Even more of a concern, i noticed that i am running at higher rpms throughout all speeds and gears. For example, in 6th at about 70mph i am running at 3000rpm or a little higher......I never remember rmps this high at this speed.

I F'in love this car and am very concerned about this! Could anyone please provide input/advice on the matter.

Thanks alot.
 

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Did you disconnect the battery (or just the negative terminal) while/after installing the intake? It's relatively normal for the idle to be weird for a couple days after resetting the ECU while it relearns fuel trims. I wouldn't worry about it. As for the RPMs being higher while in gear, that's impossible ;)
 

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double check your connections for leaks. might be a vacuum leak?
 

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Discussion Starter · #4 ·
Yea i did disconnect the battery when i installed the cobb but did not notice any higher than normal rpms till today (5 days later after oil change..).

What is the best way to check for vaccum leaks? All connections look good and clamps are tight. However, when i was doing the install i did loose grip of the hose clamp that connects the 90 degree elbow to the intake. This snapped and chipped off a little blue piece on the plastic elbow. The connection still seemed good and i cant feel any air being released in or out....

Thanks for the feedback so far. Anything more would be appreciated!
 

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i thought 3,000 rpm at 70 mph is normal.

Was your car fully warmed up when the idle wouldnt go below 1,000?
 

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Where in Herndon are you located? I work by Worldgate. If you want, you can stop by and check out my 08.5 speed 3 for comparison.
 

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Discussion Starter · #8 ·
Benben, i am right around there. I actually belong to worldgate and frequent the TGI fridays up there on the weekend. Definitely would not mind checking out your speed. The one kid i knew around here with another speed3 moved out west...
 

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if you had a vac leak enough to raise the idle to 1000 rpm... it wouldn't be enough air to make a diff once the engine is at 3k. Sounds more like the tach reads slightly high. Does a scantool RPM readout match the tach? I remember seeing in the mz6 manual there is some tolerance for tach/spedo and actual. I assume the 3 is the same. I'll play with the tach/scan tool readout on the way to work tomorrow
 

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your rpm at speed is related to gearing. The only way it can change is if you change the gears or your clutch is slipping 3k rpm at 70mph is 6th is completely normal. The car idles higher than 1000 when its warming up.
 

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You are clearly burning out in all gears.

Congratulations sir on this great feat of hoonery.
 

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Discussion Starter · #13 ·
So this morning when i started my car my rpms went up to 2k. After about a minute and a half they decrease to 1k. When i got to work 40 minutes later my idle was right around 750rmp.

Do I have anything to worry about here or am i just being paranoid??
 

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Normal. you're just paranoid. now take these pills and call me in the morning if you don't feel better.
 

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+1 agree with ForestGrump & dread!

when cold outside most of the manuals i have driven in the past and my MS3 go straight to 2K - idling high when cold, and of course when it warms up, goes down the 1K range...all ready to rock and roll ;)
 

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am i the only one that noticed that he had his first oil change at 7500???!!!!! wow dude!!! you needed an oil change at a 1000, then 3000 in between.

make sure you warm up your car before you drive it. the temperature gauge needs to reach the first line before driving. after, drive easy until it's up to operational temperature.
and rpm high at starts is normal.
 

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Discussion Starter · #19 ·
Yea I know 7500 is late. My car was hit by some idiot while i was parked on the side of the road and as a result i have been in and out of body shops since november... I was more worried about getting my suspension fixed correctly than the oil change.
Plus the users manual says for schedule 1 the first service/oil change should be around 7500 miles so i wasnt stressing it.

Thanks everybody for the feedback and easin my worries.
 

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=( I was hit in Jan while in a parking lot. Guy backed truck into me. Luckily his insurance is going to cover the repair+rental car. However, I'm so paranoid that I've been to 4 body shops so far and haven't picked a bodyshop to do the work yet. Thankfully the statue of limitations is 3 years...so I got time.

Back to your orig question of how to find vac leaks. Well, if you have a vac gauge/scantool you should be able to see manifold pressure. Dashhawk reads -15 psi and -18 deg timing when I first start (idle at 2k) and it settles down to -20 psi and +15 deg timing after 30 sec or so. (these are numbers from my bad memory so take it with a pound of salt).

another way is to spray around with carb cleaner (or anything flamable..use propane if you don't want to be spraying solvents/harsh chemicals acetone, methanol, BTEX, etc). When you hit the vac leak it will suck the stuff in and correct the A/F ratio. You'll hear the idle change when that happens.

Grump
 
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