Boost problem after 5000 rpm, car falls flat, no power
08-21-2012, 02:09 AM
#16
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If by some chance you got bad fuel, or phase seperated fuel it will run terrible. I only mention it because everything was fine until you ran low and refueled. Do you have a wideband to monitor what is going on when the symptoms show up?
Wiring harness like Bruce said. It can make some funky symptoms appear.
Good luck
Wiring harness like Bruce said. It can make some funky symptoms appear.
Good luck
08-21-2012, 08:19 AM
#17
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Join Date: Sep 2005
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That is somewhat how it will feel if you try to do it all yourself. I don't suggest it anymore. Not for a car that isn't competing.
My only update on this was that I have pulled the DME apart to check if maybe the chip was a factor in all of this. But it is seated just fine. As far as bad fuel. I thought about that, but have added more fuel (from a different place)to the car while trying to diagnose what is going on.
My plan is to buy new plug wires, cap and rotor. See if this does anything as they could use a replacement.
My plan is to buy new plug wires, cap and rotor. See if this does anything as they could use a replacement.
If by some chance you got bad fuel, or phase seperated fuel it will run terrible. I only mention it because everything was fine until you ran low and refueled. Do you have a wideband to monitor what is going on when the symptoms show up?
Wiring harness like Bruce said. It can make some funky symptoms appear.
Good luck
Wiring harness like Bruce said. It can make some funky symptoms appear.
Good luck
10-05-2012, 07:38 PM
#18
Updating this thread as I have not found a solution yet.
I have checked the Throttle Position sensor and it is operating properly according to clarks garage procedure.
I replaced plugs again, and bought new wires, cap and rotor. Already have a new coil.
nothing has changed except car fires right up. If I disconnect the Oxygen sensor the car does not surge and runs smooth if I do not push it. Once I try to boost the car sputters and makes 0 power.
I need to figure out how to eliminate the DME from being the culprit. Any way to check it? Or anyone in the San Jose area have one I could borrow to see if that is the problem?
I have checked the Throttle Position sensor and it is operating properly according to clarks garage procedure.
I replaced plugs again, and bought new wires, cap and rotor. Already have a new coil.
nothing has changed except car fires right up. If I disconnect the Oxygen sensor the car does not surge and runs smooth if I do not push it. Once I try to boost the car sputters and makes 0 power.
I need to figure out how to eliminate the DME from being the culprit. Any way to check it? Or anyone in the San Jose area have one I could borrow to see if that is the problem?
10-05-2012, 08:34 PM
#19
My car had pretty much the same symptoms.Found a loose(not disconnected)vac hose behind the cyclic valve pushed it back down and the car ran great .Keep looking for vac leaks.
10-08-2012, 01:33 PM
#21
It did start out of the blue.
I went from the car driving well one evening and everything was normal enjoying the M-tune. To the next morning I start the car up and it shakes badly, barely holds idle and has run like crap since then. In trying to figure it out I have, replaced fuel filter, replaced whole ignition, tested the TPS (checked out ok.) Looked for vac leaks.
I am thinking maybe I should take the manifold off and look for more possible leaks.
I went from the car driving well one evening and everything was normal enjoying the M-tune. To the next morning I start the car up and it shakes badly, barely holds idle and has run like crap since then. In trying to figure it out I have, replaced fuel filter, replaced whole ignition, tested the TPS (checked out ok.) Looked for vac leaks.
I am thinking maybe I should take the manifold off and look for more possible leaks.
10-11-2012, 09:41 PM
#22
To close this thread with what was the solution.
Two things were wrong. Both vac leaks.
One being a crack at the bend in the metal barb/connection on the bottom of the throttle body. Hard to detect until I took the manifold off.
Second is the Coupler connection to my throttle body. I have a cheap garbage one that looks like it is fitted, but not well enough. Again hard to figure out until I started twisting it and examining. So my solution is to order a high quality silicon product that will "seat" better with the clamp. If anyone knows what the dimensions of that coupler is that would be great.
Glad the car is much closer to being road ready
Two things were wrong. Both vac leaks.
One being a crack at the bend in the metal barb/connection on the bottom of the throttle body. Hard to detect until I took the manifold off.
Second is the Coupler connection to my throttle body. I have a cheap garbage one that looks like it is fitted, but not well enough. Again hard to figure out until I started twisting it and examining. So my solution is to order a high quality silicon product that will "seat" better with the clamp. If anyone knows what the dimensions of that coupler is that would be great.
Glad the car is much closer to being road ready
