My MAF is fine. I've tried multiple intakes and MAF's from working cars. Also my BOV does not vent to atmosphere.

Honestly boss I couldn't tell you I don't tune the car just build it. From what I understand my duty cycle is not passing 100% tho.

 

Idk. I'm going to feeler gauge the valve springs while idling the car this weekend and inspect the head. I really am thinking it has to be in the head at this point I'm out of things to try. I don't want to switch to SD yet because the car should not have these issues. I know and read about people with almost identical setups all the time that don't experience these problems. I don't want to mask the issue I want to fix it.

PS When I was younger I installed POS bc valve springs in the car also which who knows...

 

did you try unplugging the maf and seeing if it will idle better?

 

Yes. When you unplug the maf the idle goes erratic.

 

I think MrFred is putting you on the right track. If your hardwired fuel pump is overrunning your fuel system then additional fuel is being forced through your injectors. Your ecu sees a rich condition and tries to pull fuel, but wit the size of your injectors the changes made cause a dramatic shift to a lean condition. The ecu again tries to compensate and the result is a dramatic rich condition. This is more pronounced if the trims haven't been dialed in, which they couldn't have been, given the nature of the condition. Search for the thread that explains how to drill out the siphon tube in your fuel pump assembly and start with that. Until you take care of the potential mechanical issues, changing the tune is pointless.

 

I believe that Mr.Fred told you to reset the ECU was to reset the full trims. Although you don't "see a reason why it should be done", why not do it anyway? Seems like you are doing everything else to run in circles.

All you need to do is disconnect the battery for 15 seconds. If it doesn't work oh well. If it does that's awesome. Give it a shot instead of fighting it due to an assumption that it would have no effect.

GL finding the fix! Sounds like the car will be a lot of fun once the issue is sorted out.

 

I had some of the issues you were having and changing the ecu fixed them all. You should try and borrow an ecu and see if it helps, easy to do and might fix it. My tuner had never seen the ecu cause this before but the car is now fixed

 

did anyone check the air filter support? The filter can vibrate at idle causing erratic maf readings. saw this with earlier hks filter system installs. good luck.

 

Fuel pressure at the rail is perfect though? Problem is also sporadic.

Did this many of times.

Really. What was the cause of the ecu problem?

 

PM sent.

This problem ever been fixed?

 

Here's a shot in the dark. Aby has seen the BISS screws degrade over time. He made a thread about it a long time ago...don't know where it is. But BISS screws have been known to start disintigrating.

Have you removed the BISS to manually inspect it?

https://www.evolutionm.net/forums/ev...ml#post6739895

Post #14.