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Rough idle & engine noise with new engine

  • Thread starter Thread starter jrod92
  • Start date Start date Aug 28, 2011
J

jrod92

Member
Jun 17, 2004
66
0
7
Aug 28, 2011
#1
  • Aug 28, 2011
  • #1
Just replaced the engine in my 01 cobra. had it started 2 nights ago and it ran fine with the exception of a 1000rpm idle, turned vehicle off to check oil and dipstick end broke off and went into the oil pan. i did not start the car with the piece in there. I spent the the weekend pulling the motor out to get to the oil pan. got the engine put back in and everything hooked up started her up this afternoon and now the engine is running like *****. idle is about 850 and there is a loud noise coming from the passenger side that increases with acceleration as the engine is shaking terribly. when i give it gas the rpm's take off on their own and i have to shut the car off. no codes are being thrown. hooked up the scanner and looked at parameters when running. not sure what they all mean but fuel pressure is at 40psi and TSP is at 20.2. this is a brand new engine, and i am running correct oil weight and all the connectors appear to be plugged in. sorry for the long post just want to give all the details. any help would be appreciated. thanks guys.
 

wmburns

SN Certified Technician
Aug 14, 2009
5,892
514
204
Houston Texas
Sep 19, 2011
#2
  • Sep 19, 2011
  • #2
First, check to see that the fuel pressure sensor intake vacuum reference line is connected and leak free.

TPS value of 20% at idle is normal.

Check the throttle return spring. Does the throttle linkage move freely with no binding?

Are there any vacuum leaks?

Does it sound like a misfire?

Can you post a video?
 
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