idles rough but is fine under acceleration

[Drift247365]

Hope im not reposting any thread that someone has before, but I have a 97 eclipse gst and the problem im having is that when I start the car it ends up being a rough idle and almost sounds like one of the injector poppets is sticking. Sounds almost like a ball bearing being stuck and forced to move. Also with the a/c off it will idle between 600-850 rpms. At idle the afr reads around 13.2-15.6. But during acceleration it runs fine and doesn't bog or create any drag. It has a TD05h turbo with aftermarket 44mm wastegate, hallman mbc, not sure of injector size as the guy I bought it from had them done already, greddy type s bov, and injen intake with 2g maf. Bov is recirculated and has been tested for boost leak with no problems. Any info can help. Also I only run 93 Octane with VR1 oil.

 

[Drift247365]

Is that just a part that you can pick up at the auto parts store or do I have to go to dealer to get that?
And to switch to the 1g adjustable is it a simple swap over or a PITA

 

[Mauispyder]

If I'm remembering correctly, it's a 6mm o ring. I got mine at Ace hardware. Just take it with you to be safe. I think I put a little o ring grease on it too.

 

[Drift247365]

So tries to remove the BISS and couldn't get it completely out. Tried adjusting it and it raised the idle but still has a miss/sputter at idle. Scanned codes and got a random misfire code. Also checked ignition spark advance and was jumping between 4 degrees and 16 degrees. What would possibly cause that?

 

[Mauispyder]

So, BISS is recessed, and o-ring keeps it from coming out, plus it's plastic so magnets won't work. It has to be "blown out" via upstream air intake. Easiest way is to cover BISS with a towel, take and attach your boost leak tester to the turbo and give it some compressed air. Screw shoots into towel. Or if no towel then screw shoots into ceiling and back into unknown part of engine If no boost leak tester, make one. If no patience, then you can still probably just blow compressed air into throttle body elbow, carefully seal with free hand. If you just adjust idle with biss, without following the procedure in the FSM, the ECU will fight your new biss setting and cause more weird issues. That's why I'd change the o-ring and put the BISS exactly back where it was. Then I'd see if fixing that common leak helped anything. If not, then I'd set BISS position using FSM procedure (involves grounding something first).

 

[Drift247365]

Ok thanks will definitely try that with the blt.

 

[Lou98GSX]

If you increased the idle and you still have a rough idle then your problem lies somewhere else . check your valve timing you could be a tooth off making the engine idle rough . take the top timing belt cover off put the cam dowel pins facing up and the crank pulley at top dead center . when your crank pulley is at top dead center your cam timing marks should line up .

 

[nastygsx]

any update on this I'm having the same issues