I had just recently boosted my 2000 Civic Si at 7psi. Motor is really clean and mint. Not tuned yet. When I start the car, the rpm bounces back and forth at 1 to 2.5 and this happens for about 5-10mins before it will cool down at 1 again. My downpipe does not have an o2 sensor, so would that be the problem? I've gotten responses that it could also be a sensor that I have to delete? Lastly, when the car is moving at about 50mph in 5th gear the car starts smoking white smoke all over the place. I have no clue what that is... anyone have any ideas? Comments will be appreciated!

 

List your setup, and what it is tuned with.

- Derek

 

Stock b16a2
Precision sc61
RC 550 Injectors
Walbro 255lph Fuel Pump
Spoolin Performance Mini Ram
2.25 IC Pipings and 27'x6 FMIC (I think)
HKS SSQV
38mm Tial WG w/ 7PSI Spring
3 inch downpipe w/ dt welded on (No o2 bung)
3 inch Kteller exhaust
p28 ECU w/ Crome Basemap

 

Well, traditionally white smoke means coolant is being burnt, but to an untrained eye, sometimes oil looks "white" coming out the exhaust.

Either that, or it's condensation, although that's normally harder to see at speed, and dissipates almost instantly.

As far as the idle hunting goes, pop your IACV off and clean it out. If cleaning that still does not work, go looking for a traditional vacuum leak.

Is it throwing any codes?

- Derek

 

Yeah, it's throwing the o2 sensor code and some other code. Pretty sure it's the IACV.

 

Your IACV is probably causing the surge at idle (especially if its throwing a code). Have you been boosting it on a basemap?

 

Yes I have. I don't hit full boost though, safety reasons.

 

Really shouldn't boost on a base map, but thats just my 2 cents and opinion... You never know how "good" or safe your basemap is. I would check compression etc to make sure you havent damaged anything.

 

I gotcha, I'm not driving it anymore due to Winter right around the corner. Compression is good. Checked yesterday.

 

I was warming up the car and decided to mess with the 2step... while I was doing that oil shot out the exhaust....