Please HELP, vacuum , cam timing or ?? problem
Hi, first time poster long time reader. I hope someone can help.
Up until I read a post with "unplug PCV and if crankcase has pressure you don't have in internal vacuum leak" I was all set to pull my lower off for the millionth time. I have nearly 0 vacuum and it runs like (insert expletive). Vacuum @ idle right now is 2, I have had it as high as 6. Been through more than a can of starting fluid and can’t find any external leak. The car surges and I have gone through everything I can get my hands on about idle problems and it keeps coming back to what I thought was a vacuum, or lack there of, problem.
My other thought is to pull the timing cover again and degree the cam. The crate motor came with a regular timing chain and I changed it to a Motorsport double roller. I thought maybe I put the crank gear on wrong but after pulling the cover....no such luck. I did double check and everything lined up with the stock set. I have never had to degree a cam before but I guess there is a first time for everything.
I have been fighting with this for over a year...(I hate to loose)..and recently even took it to a shop that specializes in 'Stangs...I thought maybe it was something electronic but they said everything was good...spent close to $900 for them to tell me that without tearing it completely apart they can't tell me what's wrong. They took off the intake and checked the rockers….put shims in under the pedestals. I have since redone what they did (grasped at a straw that since the motor sat a long time before I put it to use, the valves might not be seating properly….stupid move), the rockers didn't need shims...all torqued down within 1/4 to a full turn.
I pulled the codes and I got a 31, probably because the shop eliminated the EGR (any help on how to jumper/bypass this would also be appreciated) and a 66. I don't know enough about the electronics to know if that is a byproduct caused by insufficient vacuum or not.
I'm not really looking forward to pulling either the intake or timing cover again and definitely not both. Any input would be more than welcome.
Thank you very much in advance.
Hi, first time poster long time reader. I hope someone can help.
Up until I read a post with "unplug PCV and if crankcase has pressure you don't have in internal vacuum leak" I was all set to pull my lower off for the millionth time. I have nearly 0 vacuum and it runs like (insert expletive). Vacuum @ idle right now is 2, I have had it as high as 6. Been through more than a can of starting fluid and can’t find any external leak. The car surges and I have gone through everything I can get my hands on about idle problems and it keeps coming back to what I thought was a vacuum, or lack there of, problem.
My other thought is to pull the timing cover again and degree the cam. The crate motor came with a regular timing chain and I changed it to a Motorsport double roller. I thought maybe I put the crank gear on wrong but after pulling the cover....no such luck. I did double check and everything lined up with the stock set. I have never had to degree a cam before but I guess there is a first time for everything.
I have been fighting with this for over a year...(I hate to loose)..and recently even took it to a shop that specializes in 'Stangs...I thought maybe it was something electronic but they said everything was good...spent close to $900 for them to tell me that without tearing it completely apart they can't tell me what's wrong. They took off the intake and checked the rockers….put shims in under the pedestals. I have since redone what they did (grasped at a straw that since the motor sat a long time before I put it to use, the valves might not be seating properly….stupid move), the rockers didn't need shims...all torqued down within 1/4 to a full turn.
I pulled the codes and I got a 31, probably because the shop eliminated the EGR (any help on how to jumper/bypass this would also be appreciated) and a 66. I don't know enough about the electronics to know if that is a byproduct caused by insufficient vacuum or not.
I'm not really looking forward to pulling either the intake or timing cover again and definitely not both. Any input would be more than welcome.
Thank you very much in advance.
