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Intermittent startup surging

  • Thread starter Thread starter Mschrup
  • Start date Start date Mar 7, 2022
  • Tags Tags
    idle control idle issue mega squirt start issue surging surging idle
M

Mschrup

New Member
Mar 7, 2022
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Washington
Mar 7, 2022
#1
  • Mar 7, 2022
  • #1
Few months ago I installed a mspnp2, along with GT40P heads and intake on my 95gt, idling has always been an issue but the startup creeps to around 3k and hangs there for 4-5 seconds before dropping down, this is only when the car has ran in the last couple hours, cold starts in the morning don’t produce this issue, and it starts fine, I’ve tried changing every single parameter in the tune, and replaced the IAC and still no change, it’s starting to get on my nerves now.
 

a91what

SendMeUrDataLog
10 Year Member
Apr 6, 2011
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Hillsborough county
Mar 9, 2022
#2
  • Mar 9, 2022
  • #2
A datalog and copy of the tune are required to help.
Likely your ign advance is catching the idle speed and driving it up. Timing plays a large role in how the car idles and can effect idle speed faster than the idle valve.
 
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