Cold Idle Surge (Picture)

[yoyo13131]

I have a 2.0 Non Turbo 1993 Eclipse with a 6 bolt engine

ONLY on cold start my brand spankin new engine surges from 2,000RPM to 1,500RPM several times (10-20 times) until it reaches quarter way on the temperature gauge. Once the surging stops the car runs perfectly and idles at 750RPM at full temp.
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<img src="http://i85.photobucket.com/albums/k64/yoyo13131_88/Surge.jpg?t=1275614032" width="800" height="566"></a>
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When I crimp/hand close the RED ARROW hose my cold start surge is completely fixed! Whats this mean? EGR bad? Purge Control Solenoid Valve bad?

What I've tested:
All Emission hoses are good.
Emission hoses set up exactly like the picture says.
ISC Motor ohms read ok+o-ring is in place.
ISC Motor is Getting Power from harness
Top Throttle body has been cleaned properly
Brand new OEM PCV
BISS screw o-ring seems to be good since it idles perfectly after cold start.
Cars entire wiring harness is good and no shorts.

 

[And_44]

Have you checked your EGR valve? That red arrow hose when pinched may open/close the valve. I blocked off my valve and removed all my emission hoses (emission exempt for me). When I looked at my EGR valve when installing the block off plate it was almost completely cloged with coke/gunk. And your hose's may appear good, but have you changed them?

 

[yoyo13131]

Have you checked your EGR valve? That red arrow hose when pinched may open/close the valve. I blocked off my valve and removed all my emission hoses (emission exempt for me). When I looked at my EGR valve when installing the block off plate it was almost completely cloged with coke/gunk. And your hose's may appear good, but have you changed them?

Cleaned the entire EGR+new gasket, its verified working perfectly by my local machine stop... it's still doing the exact same cold start surge.

Any ideas?

 

[DSM1G90]

I trust that timing is correct using the 5*BTDC standard settings. But it could be a sluggish ISC unit on you that can't settle down the correct idle until full temp.

 

[yoyo13131]

I trust that timing is correct using the 5*BTDC standard settings. But it could be a sluggish ISC unit on you that can't settle down the correct idle until full temp.

Yep, timing was the first thing I did on first start up. 5-BTDC...
and about the ISC unit im not to sure on that. I think all signs are pointing to the Purge Control Solenoid Valve....maybe

Oh and I was experimenting with that hose that fixes my problem, if I block off that hose completely and leave the other hoses in the loop, it fixes my cold surge completely but then makes my hot idle all erratic/unstable

 

[Hesh724]

the spring can go bad in the Fast idle air valve and can cause idle issues when cool.

 

[talontsiboy24]

I have a 2.0 Non Turbo 1993 Eclipse with a 6 bolt engine

ONLY on cold start my brand spankin new engine surges from 2,000RPM to 1,500RPM several times (10-20 times) until it reaches quarter way on the temperature gauge. Once the surging stops the car runs perfectly and idles at 750RPM at full temp.
<br>
<img src="http://i85.photobucket.com/albums/k64/yoyo13131_88/Surge.jpg?t=1275614032" width="800" height="566"></a>
<br>
When I crimp/hand close the RED ARROW hose my cold start surge is completely fixed! Whats this mean? EGR bad? Purge Control Solenoid Valve bad?

What I've tested:
All Emission hoses are good.
Emission hoses set up exactly like the picture says.
ISC Motor ohms read ok+o-ring is in place.
ISC Motor is Getting Power from harness
Top Throttle body has been cleaned properly
Brand new OEM PCV
BISS screw o-ring seems to be good since it idles perfectly after cold start.
Cars entire wiring harness is good and no shorts.

Same issues im having with my 1g on a cold start as the motor is warming up my idle goes up and then down many times but not krazy only like from 1200 back down to 1000 rpms and then i will go driving the car around for a bit and the idle is stable at 850 where my chip is set and the car seems to run as it should what can it be? this started for me ever since it got warmer out here and i rewired my fuel pump because it wasnt rewired before and i went from iridium plugs to copper. before these changes it use to idle fine! oh also my throttle body nipples are all capped off

 

[yoyo13131]

Same issues im having with my 1g on a cold start as the motor is warming up my idle goes up and then down many times but not krazy only like 500-100 rpms and then i will go driving the car around for a bit and the idle is stable at 850 where my chip is set and the car seems to run as it should what can it be? this started for me ever since it got warmer out here and i rewired my fuel pump because it wasnt rewired before and i went from iridium plugs to copper. before these changes it use to idle fine! oh also my throttle body nipples are all capped off

If your having the same problem I did, I fixed mine by readjusting my FIAV spring, I took the entire throttle body off and adjusted the FIAV to open when cold, and close when hot in my sink. (I have very hot tap water) after I ajusted my FIAV its not surging AT ALL anymore now =]

 

[95gst16g]

Mine was doing that for a long time until last night.....I bought a FIAV bypass plate off ebay that allows me to keep the ISC motor and get rid of the FIAV.The only downside is I have to hold the gas for a minute so it will stay idleing on it's own.But thats no big deal for me.The car idles just fine when it warms up a bit.No surges I'm happy with it.I would recomend blocking it off because it's cheaper then replacing the FIAV haha

 

[talontsiboy24]

If your having the same problem I did, I fixed mine by readjusting my FIAV spring, I took the entire throttle body off and adjusted the FIAV to open when cold, and close when hot in my sink. (I have very hot tap water) after I ajusted my FIAV its not surging AT ALL anymore now =]

So is it the weather change cause the idle to act up on cold starts? cause this started ever since it got hot out like on cold days it dont seem to do this...and is it ok to leave it like this or its causing damage or something cause once i drive it after it warms up everything seems back to normal?

 

[yoyo13131]

Mine was doing that for a long time until last night.....I bought a FIAV bypass plate off ebay that allows me to keep the ISC motor and get rid of the FIAV.The only downside is I have to hold the gas for a minute so it will stay idleing on it's own.But thats no big deal for me.The car idles just fine when it warms up a bit.No surges I'm happy with it.I would recomend blocking it off because it's cheaper then replacing the FIAV haha

Most of the time all you have to do is readjust the FIAV so it actually closes all the way when hot or cold. I can't see how the huge spring can go bad, mine has 129k miles on the throttle body and I was still able to adjust the FIAV back into the correct position in my sink so it wont surge anymore when cold.

I would suggest taking your throttle body apart and the freeze plug and readjust your FIAV if you want to keep it stock and not have to hold the gas peddle on cold starts.

 

[Morphkool]

Thank you search. This the exact problem I've been having and now I can fix it. Thank you all who post to this site, its a great site. Long live DSMTuners.com