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gbabione
06-18-2014, 10:21 AM
I have been slowly putting this car together. It is a rebuilt motor with a Comp Cams stage 1 cam, 1.7 roller rockers, and the full blown MP performance package. All the sensors on the motor are new. My original problem of poor timing and backfiring have been solved by getting 5 & 6 plug wires in correct position.
Now the new problem. It will start easily, runs kind of smooth at first then gets rough as idle slows down. If I try to give it gas to keep running, it's real rough and I have to keep going up and down with throttle. Too much pukes it out. After a couple minutes of that I can't keep running. I can start right back up and go through the same again. Yesterday I kept doing it until it warmed up. Once it did, it stayed running on its own. I adjusted 2 screws on TB and have the idle around 800 rpm. If I give it gas, it still doesn't like it. While idling, I sprayed ether around lines and couplings to check for leaks. No change in motor so I'm guessing no leaks.
Any ideas would be appreciated.

SCrazy
06-18-2014, 10:24 AM
I would first double check for vacuum leaks and fouled plugs. Sounds like you've got the vacuum leaks covered.

David Neibert
06-18-2014, 11:01 AM
Any check engine lights or codes ? Are you sure the cam position sensor stalk was installed in the correct position ? Still using stock injectors and MAF ? Are you using any tuning device or still running on the stock tune ?

David

BirdofPrey97
06-18-2014, 11:26 AM
Fuel pressure? With the vac lines cleared a fuel pressure gauge installed in the fuel rail would be my next move. Verify all injectors are inserted and hooked up completely.

gbabione
06-18-2014, 11:38 AM
I believe the package included 60# injectors, an 85mm TB, and a Ford Lightning MAF meter. I have a chip from XR7Dave with a safe tune for what u have until it's running and he can tune it. Cam sensor is at 30* to front of motor. Fuel pressure is 40 psi. I didn't check while it was idling.

jdsgallops
06-18-2014, 04:31 PM
Sounds like a timing issue to me. I would verify the cam sensor and check timing with a timing light to verify it is correct.

David Neibert
06-18-2014, 04:48 PM
I believe the package included 60# injectors, an 85mm TB, and a Ford Lightning MAF meter. I have a chip from XR7Dave with a safe tune for what u have until it's running and he can tune it. Cam sensor is at 30* to front of motor. Fuel pressure is 40 psi. I didn't check while it was idling.

The 30 degree portion of the installation is probably the least important and is only pointed in that direction to clear the belts. The main things are correct engine position when installing the stalk (26 degrees after top dead center with #1 cylinder on the compression stroke), and where the vane of the stalk is located in relation to the sensor. This thread has all the information needed to install the stalk correctly.

http://www.sccoa.com/forums/showthread.php?46483-Cam-Syncronizer-Positioning-How-to&p=365956#post365956

David

gbabione
06-21-2014, 09:00 PM
Here are 2 pictures of stalk showing correct orientation and vane in middle of notch. Fuel pressure stays at 40psi while idling. #1 cylinder looks to be firing at 30* btdc. If I pull the spout plug it is at 10* btdc and shuts down right way. I still need to check for spark on all cylinders.

jdsgallops
06-22-2014, 01:38 AM
Reread what David posted. I just had a no start problem on my refreshening and David had it pegged correctly. The balancer has to be at the notch which is 26*. Then install the stalk and set the vane correctly.

gbabione
06-22-2014, 08:45 AM
I forgot to say I have a BHJ balancer. I measured the 26* atdc line before installing and it's the right distance from 0*. Those pictures are with the 26* line on the pointer.

XR7 Dave
06-22-2014, 11:23 AM
Fuel pressure at idle is normally more like 34-36psi. Is the vacuum line connected? The line should be off and plugged when checking fuel pressure. If you disconnect the line it will read 39-40psi. Make sure that fuel pressure is changing with engine vacuum/boost.

Ignition timing is not externally adjustable so there is no point in checking it. If the cam sensor is timed right then the only thing remaining is insufficient fuel delivery. This may have to be adjusted in the tune. If it starts easily and you are sure you don't have any vacuum leaks, then I'd say it's ready for tuning.

Jacob_Royer
06-22-2014, 12:18 PM
A non stock cam with the stock tune will not idle to save youre life!

gbabione
06-22-2014, 08:36 PM
I just checked fuel pressure with vac line off. It was 40#. I connected line and adjusted down to 36# and it ran worse. I started adjusting up until it ran good. When I got it to 60# it will run on its own and will allow me to rev it some. I can even hold rpm at 2000. The KOEO code I get is 511 as expected for new chip. The KOER codes I get may be false because I never got a pulse to start. What I got was 136, 172, (both lean condition codes), 412, and 538.