I have been trying to figure out this puttering issue for a couple of weeks now.

Here is the situation the car was running perfectly fine until i put my fmic. After installing my fmic I did do a couple runs here and there and no issues. Well after sometime the car started to putter a bit under boost. It would start around 4k rpms or when i was at full boost. I assumed its probably a tune-up issue or boost leaks, something minor.

Well I went to go pull out my spark plugs and the previous owner had put in "champion" plugs so i replaced them with OEM NGK's. Next, I did a boost leak test and found that my pos greddy bov was leaking after 5psi. I went ahead and got a synapse bov. Now the car has no boost leaks. (30psi tested).


I take the car on the road and the puttering got a lot worse. Anytime Im on the throttle more than 50% it putters. NO CEL on...need some guidance on where to go...
I just got new wires and boots from the dealership, gonna install them today but don't think that will fix this issue.

I did throw a code for a MAS but thats cause i started the car with the MAS unplugged. I swapped MAS's with another evo just to be sure and still the same issue.


History of the car, has a turbo-back exhaust, ETS FMIC, synapse bov, fresh tune-up, evo9 turbo, exedy twin disc, manual boost controller, prosport boost gauge, aem wideband, walbro 255 pump, and a tune by me. I used evoflash/evoscan to tune it.


Do i need to redo the tune, I cant really get a solid afr cause i get off the gas when it putters...

 

Just an update, I changed the wires no luck. While I was changing the wires a buddy came by so i swapped over coil packs just to be 100 percent sure and still no luck. I feel as if im playing "guess what part.." lol any advice...

 

Post a log.

 

this is prob a new'b question but how do i post up my log from evoscan? It wont allow me to attach a log in excel format..

 

Here is a log...I could not hit redline because it was puttering too much..these pulls start off in 2nd gear.

 

anyone, any advice...

 

Did you get re-tuned after fmic install and bov?

 

What you have your plugs gap at?

 

I did not re-tune it after the FMIC or the bov install.
The plugs i have are pre-gapped OEM plugs!

For the synapse bov i just purchased, I did not hook it up to a boost source just a vacuum source. The 2 plugs in the back, i t'ed them to a vacuum source. It does not look like it needs a boost source...I read earlier that the new ones use the boost source from the intercooler pipe.
I just want to double check i hooked it up right.

 

I think it might have to do with my BOV, after reading Synapse's wesbite i can see that i am suppose to have a port c for a boost source but my bov doesnt have a port c.

Im going to attach some pictures, does it look right?
I also took a close up pic of the bov where there should be a port c!

 

Just to add, i changed out my bov to a buddy's greddy bov but same thing. It is partial throttle stumbling and wont go away!!!

 

well it feels like this is a personal blog lol

so just for anyone else having this issue ever I want to say i found the solution.
The plugs i got from the dealership were bad. I went to NAPA got ngk bpr7es plugs and gapped them to .025inch and the car ran like it should!

 

u dont need port c on the new synapse's bov...with your mods i would of gone bpr8es one step colder plugs....

 

hmm, well take simple steps?

Check for boost leaks using the water/soap way.

Check your compression across all 4 cylinders.

I'd honestly regap your plugs yourself. The plugs although they say they are gapped.. may not be gapped correctly. This happened to me a while back, I had to go back in and regap them.

I'm not sure about the evo intake manifold, but on my lancer's manifold, there are nipples for egr & some other things. Make sure all those lines are sealed off, otherwise your motor will ingest un-maf-measured air. That caused puttering for me.

 

On the new Synapse BOV Port C has been internally plumbed and take the pressure directly off the charge pipe.

this makes install easier and you dont have to worry about tapping a boost source.

A+B into vacuum and your done.

Devin
Synapse