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Discussion Starter #1
Hi hope you all can help me look at my evoscan log

No boost leak, new iac, new tps, new ptu, new spark and wires

Tested maf, reset biss, rebuilt tb

Still keep getting idle stutter in close or open loop
Worse at cold, better at warm, but still present

Cannot upload so posted it online here, thanks!
 

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1991 Dodge Stealth ES 5sp
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Did you pull out your ECU, open it and examine it? looks like you replaced all the other culprits already.
 

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Are you sure you set your idle correctly, as in grounding the diagnostic pins(obd port and engine bay)? Because your idle is quite high(900-960 at temp), when I think it should be 700 +/- 100 at idle with no load on the engine. You also don't see any ISC steps until about 735 seconds in when the throttle gets blipped to about 20%. Did you actually touch the throttle there? Because it looks(at least based on the log) like you touch the throttle, ISC counts go up with RPMs, then you let off and it nose dives.
 

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Discussion Starter #4
mini_cal, I did not. It's relatively new; about a year and it's a jester, not stock ecu. Aplogy, forgot to mention that.

rossb, idle is set but I had to turn the biss screw out a little bit more to not cause it to stall. It will stall if I keep it around 700. Yes, I did blip the throttle to make sure my tps was reading accurately a couple times towards the middle of the log. It wasn't necessarily the throttle if you want to be specific, but the butterfly valve on the tb under the bonnet. Is the nose dive of concern?
 

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Well if you set your idle properly(grounding diagnostic pin on OBD port, and grounding idle adjust connector in engine bay), then you backed out the BISS screw afterwards without grounding them again, that might be your issue. If your engine wants to stall when idling around 700rpm that's a symptom not a cause, and you obviously have a problem somewhere. The fact your RPMs nose dive after a quick throttle blip might be telling. It looks like you are suddenly missing something that should be there, like air or fuel, before it quickly recovers. Do you have a vent to atmosphere blow-off valve by any chance?
 

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Discussion Starter #6
I use evoscan to put the car is SAS mode

I tried again to your point and raise the idle to 850 in SAS and same issue and also had set target idle to 850 in ecuflash

I do have a tial qr bov but it is recirculated
Dunno if my log rate is just too slow to show a steady drop when I blip the butterfly valve??? It was just really quick so I can see my TPS is going up so wouldn't rpm also drop quickly too??

What else can I check? As for AIR missing, what else is left to look
FUEL, doesn't sound like misfiring so injectors should be ok
Can fuel pump and fuel filter cause idling issue?
 

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Alright so I assume the "SAS mode" is the "speed adjustment screw" setting in evoscan. I'm not sure that actually works with our cars. Looking around the forums seems to give conflicting results. Why don't you try setting the idle the old fashioned way like the factory service manual says to? It takes all of 2 minutes to setup. Ground pin 1(diagnostic pin) on the OBD connector(looks like you are already logging over OBD so you've already accomplished this step), then ground the speed adjust connector in the engine bay. Your idle should immediately change and your check engine light should be illuminated. Turn the BISS until your RPMs are 700ish, and turn the car off, undo the speed adjust ground and fire it back up.
 
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