Issues with the beast, bucking under heavy accelertation and general loss of power
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Joined: Aug 2010
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From: Vancouver Canada
MB
Issues with the beast, bucking under heavy accelertation and general loss of power
I've felt my car being slower than normal lately and today when I tried to get on it hard, the car will buck and give me no throttle response for a second and then its back. But nothing close to the power it should have returns to the car.
Now 2 months ago I was having starting problems where it wouldnt crank the first time but would the 2nd or 3rd. I pulled both my fuel pumps up and checked for loose connections, everything was ok. After putting them back in my starting problems were gone and now todays problem starts with the bucking. So my guess is im losing fuel pressure in higher rpms and then the car goes into a limp or safe mode to prevent damage, which is the bucking im experiencing? Any other things to check before I order up new pumps?
Now 2 months ago I was having starting problems where it wouldnt crank the first time but would the 2nd or 3rd. I pulled both my fuel pumps up and checked for loose connections, everything was ok. After putting them back in my starting problems were gone and now todays problem starts with the bucking. So my guess is im losing fuel pressure in higher rpms and then the car goes into a limp or safe mode to prevent damage, which is the bucking im experiencing? Any other things to check before I order up new pumps?
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From: BC
Haters crazy
Grab my scan tool and data log, see whats going on with your IATS as far as the loss of power goes. Weathers been hot lately, and on stock cooling it kind of blows...
Have you replaced your crankshaft position sensor? (For starting issues)
Have you replaced your crankshaft position sensor? (For starting issues)
Senior Member
Joined: Aug 2008
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From: Toronto
2004 E55
same thing happened to me....i think it depends on how severe the bucking was...wasnt my IC pump as my check engine came on same time, problem seemed to be some sensor in the emmissions system.
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e55
I had similiar issues awhile back. Dealer diagnosed it as a slight misfire. They recommended new spark plugs or coil packs. I did neither at the time, but by the time they reassembled it after testing, the issue was gone. My suspicion was a loose spark plug wire, so check those first, make sure they're all tight.
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From: BC
Haters crazy
Test the IATs today, they were 100 degrees in the city, 120ish after WOT, and would come back down to 110 range...
Pump seems to be working, supercharger is engaging...
So that possibility is out of the question.
Pump seems to be working, supercharger is engaging...
So that possibility is out of the question.
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Joined: Aug 2010
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From: Vancouver Canada
MB
Yeah thanks again Tony! My pump was changed to a cm-30 about 3 mths ago and is working good. Before the failing stock pump was showing IATS up to 180. Im gonna check my fuel pressure on the rail tomm, anyone know what it should measure?
