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Greetings all,
So I've been enjoying my rebuilt 4.0 carrera for some time now and have observed an odd behavior twice now. Twice now the car is low on power when I drive it. Then, I'll park it and come back and full power is back. So to expand, when I go WOT on each gear change there is a significant reduction of power. Even at a stop and I just rev it up it doesn't sound as powerful.
< 3000K mile rebuilt engine
new injectors
new clutch
No CEL
I've got a Durametric so if there's something I should monitor while driving, let me know. Thanks!
I would monitor crank position and the variocam timing angle. Not the deviation. See if they r activating? Fuel may also be an issue. Its hard to monitor fuel pressure but maybe the pump is failing. Get a gauge and start checking it.
Did you use stock motor mounts or aftermarket? If you went aftermarket, dollars to doughnuts the ecu is picking up signals to cut power from the higher vibrations transmitted to the engine that the stock mounts would absorb.
Easy-peasy to get on the right path if you "log" the values of TP , MAF, ignition timing, Camshaft timing, 02/AFR readings,RPM, to compare at WOT when you have the power loss to the WOT when there is no power loss...
The values that go astray will take you on the right path...
Did you use stock motor mounts or aftermarket? If you went aftermarket, dollars to doughnuts the ecu is picking up signals to cut power from the higher vibrations transmitted to the engine that the stock mounts would absorb.
Easy-peasy to get on the right path if you "log" the values of TP , MAF, ignition timing, Camshaft timing, 02/AFR readings,RPM, to compare at WOT when you have the power loss to the WOT when there is no power loss...
The values that go astray will take you on the right path...
@Porschetech3
i pulled some codes from the ecu P1235 and p0123
based on that I monitored TPS 1 and 2.
At WOT but since it’s in limp mode I could only get the engine up to around 5k rpm before I run out of runway.
RPM: 4989
TPS1: 1.25
TPS2: 3.73
MAF: 251
I've been bad about providing updates to issues so I want to correct that now. Issue resolved:
I wanted to give you a heads up on my electrical issue. I FOUND THE ISSUE! It was also the issue with my fuel tank pressure sensor. Check out the picture. It seems that when I put the interior back together I severed a few wires in the harness with the seatbelt bolt. The pedal position sensor wires and the 5v wire to the fuel tank pressure sensor were affected.
seatbelt bolt right through the harness.
Nice job Yogi on sticking with it to find the root cause of the fault codes....Kudo's to doing THE REAL WORK OF DIAGNOSING AND FINDING THE CAUSE !!!!
Wiring issues are always the hardest to find ...hard fault trouble codes can always have one of three causes.... (1) the component . (2) the DME/ECU/Controller (3) The WIRING in between !!
Nice job Yogi on sticking with it to find the root cause of the fault codes....Kudo's to doing THE REAL WORK OF DIAGNOSING AND FINDING THE CAUSE !!!!
Wiring issues are always the hardest to find ...hard fault trouble codes can always have one of three causes.... (1) the component . (2) the DME/ECU/Controller (3) The WIRING in between !!
This reminds me of a story told by a friend of mine a long time ago who worked as a tractor/trailer mechanic for a trailer manufacturer. While they were building the trailers sometimes wiring would get pinched and/or otherwise damaged during assembly. Their troubleshooting method was to get 4 people to stand around the trailer, apply 24 volts to the wiring, and look for smoke.
This reminds me of a story told by a friend of mine a long time ago who worked as a tractor/trailer mechanic for a trailer manufacturer. While they were building the trailers sometimes wiring would get pinched and/or otherwise damaged during assembly. Their troubleshooting method was to get 4 people to stand around the trailer, apply 24 volts to the wiring, and look for smoke.
Wow.. that must have taken some digging, looking forward to watching your video on YouTube, seems like you would have felt that when you where putting the bolt in, must have had to uga-duged it