Engine Performance This section is for discussion on all engine building related questions.
Sponsored by:
Sponsored by: KPower

Weird VVT problem OR major loss of power

Thread Tools
 
Search this Thread
 
Old 01-11-2013, 02:09 AM
  #1  
Newb
Thread Starter
 
TurboFire's Avatar
 
Join Date: Jan 2013
Posts: 1
Total Cats: 0
Default Weird VVT problem OR major loss of power

I have a 02 completely stock miata.

Now once the coolant gauge moves above a little less than 1/4 from cold, i notice power loss.

When the car is cold i can feel what is the best easily described as vtec at about 3500 rpm, even at 10% throttle.

When the car is warm i lose the feel, and in higher rpms, you can really notice loss of power, basically a bad tune, no miss or anything like that.

No CEL or any problems, just lost of power.

I feel its VVT not working, but i dont know why it works when cold but not hot.

Just need some insight.

Thanks
TurboFire is offline  
Old 01-11-2013, 02:45 AM
  #2  
Former Vendor
iTrader: (31)
 
Savington's Avatar
 
Join Date: Nov 2006
Location: Sunnyvale, CA
Posts: 15,442
Total Cats: 2,099
Default

VCTS solenoid issue?

e: Or a clogged cat?
Savington is offline  
Old 01-11-2013, 10:02 AM
  #3  
Junior Member
iTrader: (1)
 
GraemeD's Avatar
 
Join Date: Sep 2009
Location: Colorado
Posts: 166
Total Cats: 6
Default

Disconnect the VVT plug and go for a drive, see if it is different. (I don't know if it will produce a CEL)
GraemeD is offline  
Old 01-11-2013, 10:35 PM
  #4  
Elite Member
 
flounder's Avatar
 
Join Date: Mar 2010
Location: Detroit
Posts: 1,524
Total Cats: 31
Default

What's the mileage and have you ever had a tune up?
flounder is offline  
Old 01-12-2013, 09:26 AM
  #5  
y8s
2 Props,3 Dildos,& 1 Cat
iTrader: (8)
 
y8s's Avatar
 
Join Date: Jun 2005
Location: Fake Virginia
Posts: 19,338
Total Cats: 573
Default

are you sure your'e LOSING power when it's warm? or you just can't feel the change from super super slow to regular power levels?

The VTCS does work like that. When cold, it closes butterflies up to a certain RPM and then opens and it CAN feel like a woosh.

But when the car is warm, the butterflies are always open. So if you want to test this, you can unplug the VTCS actuator and get the same feeling hot or cold. It may run like **** until it warms up a LITTLE but it will still be a valid test.

I don't have a good picture but it's the wastegate looking thing under the throttle body that attaches to the intake manifold. There's a little green (or green and black?) valve in the vacuum line. You can disconnect it there and plug the side that DOESNT go to the actuator.

Anyway. Try it.
y8s is offline  
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Full_Tilt_Boogie
Build Threads
84
04-12-2021 04:21 PM
Rick02R
WTB
3
01-03-2016 07:18 PM
mx592
Suspension, Brakes, Drivetrain
1
10-01-2015 12:45 AM
interestedofold
Suspension, Brakes, Drivetrain
5
09-29-2015 01:42 PM



Quick Reply: Weird VVT problem OR major loss of power



All times are GMT -4. The time now is 08:50 AM.