Ok for the past month now my car has been having an idle/rpm issue. For the life of me I cant figure it out. Im hoping one of you FI Gods can figure it out or at least point me in the right direction.

Ok so I have a Procharger....stock block running off a Greddy EU. When I rev the car or pull up to a light and put the clutch in the RPM's drop really low almost like its going to stall out. It hasnt stalled yet but that doesnt make it right. It drops down to like 450rpm then comes bacl to 650ish.

So far I have tryed this....Changed the plugs, check for exhuast leaks, check for vacum leaks from the BOV and done an ECU reset. Still didnt fix it. I think its still a vacum leak...I was also thinking coils but its not running rough. AF is good so is timming.

Anyone have any clue what it could be. I looked in the manual but I dont know where to start and even though I know about cars I dont want to start messing with crap.

Any help would be great or Ill just have to take it to GT or Blast have them check it out. Its not even throwing a cel which would make life so much easier.

Thanks

Avo

 

I don't know what to say. I had the same issue before FI. I got the idle raised for the Vortech noise and it helped with the idle too. I think maybe the Vortech's parasetic pull on the engine at low speeds may have something to do with it. My only advice would be to raise the idle to 750 rpm.

 

had that problem once before.took it to Performance Nissan to have the idle raised,problems solved.

 

what would parasitic losses have anything to do with this?

want to know the real cause? it's the emanage ultimate

raise your idle up to something like 8500-1100 rpms and you'll be good

 

The Emanage wouldn't explain why I had the same problem and I don't have Emanage. Secondly, I never mentioned parasitic loss. I mentioned the SC being parasitic in nature even at idle. The crank is still pulling the SC even when the car isn't boosting. Feel your BOV at idle and you'll feel air shooting out. That's from the SC, thus the crank is still turning the SC. Whatever power it takes to turn the SC at low rpm or idle was not accounted for when the car was designed, so naturally the idle rpms will be weak while coming to a stop. To compensate for the extra drag, raise the idle speed.

 

good explanation

 

Thats guys I didnt have it before i noticed it after I changed my BOV to the Vortech cuz the stock ATI is a joke. I could make a better one with legos.

I stopped by Performance today to ask Jason and he said just raise the idle to 800 or so and you should be ok. Im gonna wait till I get back from SEMA to do it and I think the EU can do it too. If not its only $50 at Performance and it takes a few min.

Thanks for the help again

PS- I dont know why youre ******* the Emanage Ultimate unless your running Motec or Fcon you have no ground to stand on.

 

I've had more problems with the emanage ultimate than anyone wants to ever know about...my car runs soooo much better without it now

 

That sucks at least you solved most of it. Maybe it was from the Tuner?????

 

lots of little things like start up. With the EU, it'd chug and chug and chug and then finally BARELY turn over and sputter up - very pathetic sounding actually. Without the EU, the car aggressively fires up IMMEDIATELY

that and burning 3 coils out, having the car actually TURN OFF the ignition while driving - one time when I was doing a fast turn, almost hit a car when I realized I didn't have power steering anymore

also the car would burp and hiccup sometimes with it

I also have a brand new HKS ignition amplifier that flat out won't work with the EU

just glad to be rid of it. I'm using an ECU flash for now, and will add the mighty SS box on top of it for fine tuning - nothing fancy, but at least it works right

 

CRC MAF cleaner. Will probably help a little. My rpms would bounce between 600-700 after moderate driving, and after cleaning the MAF, it stays pretty even at 600rpm. Doesn't move up and down as much.

 

that could be the problem of the crappy idle. a bov should be completely shut unless the plenum induces a vacuum which causes the bov to open and to release charged air.

 

I changed the stock one to the Vortech one. sounds and works great. Im gonna take it to Churches when I get back from SEMA maybe have it tuned and checked out again.

I just cant wait for the built motor with TT and Fcon V pro shouldnt have a headache in the world but Tires and Tickets

 

Maybe we're talking about the same thing:

When the BOV is open-air is not allowed to enter the engine and is routed through the BOV. This happens at idle or any situation when vacuum is greater than + or - -5hg/mm.

When the BOV is closed-air bypasses the valve and is allowed to enter the engine...you're officially boosting


For those reasons, the correct term is actually bypass valve. The BOV on a turbo car acts is a similiar fashion, but it doesn't have continous air from the intercooler to deal with after letting off the throttle. It's safe to say that as your rpms fall, so does your exhaust gases. So any residual air produced by the turbo is vented. Unlike the supercharger, which is always producing air. When you let off the throttle in a Vortech SC, it also vents, but continues to vent the air being produced by the SC.

For the original poster: Also check the hose from the filter to the throttle body and make sure your filter is clean. This is the only air source for breathing when your car is at idle due to no air being allowed into the engine from the SC.