Kevspec 0 Posted March 13 Share Posted March 13 So car has been converted from na to turbo and been running fine since then I have upgraded the turbo and when we are trying to retune anything above 4500rpm cam control seems to be advancing itself and not responding to anything we tell it to do above 4500 under load. There are no faults at all and we tried another set of solenoids all no change Quote Link to post Share on other sites
Roland@pcmtec 1,525 Posted March 13 Share Posted March 13 What is the cam angle error on the datalog? Can you post a datalog. Are you running stock cams and valve springs? Quote Link to post Share on other sites
Kevspec 0 Posted March 15 Author Share Posted March 15 On 3/13/2021 at 11:48 PM, Roland@pcmtec said: What is the cam angle error on the datalog? Can you post a datalog. Are you running stock cams and valve springs? I will get a log. No faults crow springs bf turbo cams in fg gas motor. It was all tuned and fine before only thing that was changed was the turbo Quote Link to post Share on other sites
Puffwagon 80 Posted March 15 Share Posted March 15 I've had a similar issue where the cams wouldn't respond at all and were locked at -10. I swapped the solenoids to no avail and the fix for me was swapping the phasers/gears. Quote Link to post Share on other sites
Kevspec 0 Posted March 15 Author Share Posted March 15 4 hours ago, Puffwagon said: I've had a similar issue where the cams wouldn't respond at all and were locked at -10. I swapped the solenoids to no avail and the fix for me was swapping the phasers/gears. They work fine with normal loads but under full load there dropping to low retard Quote Link to post Share on other sites
Roland@pcmtec 1,525 Posted March 15 Share Posted March 15 1 hour ago, Kevspec said: They work fine with normal loads but under full load there dropping to low retard You possibly have an oil supply issue then. What pressure are the valve springs? Quote Link to post Share on other sites
Kevspec 0 Posted March 15 Author Share Posted March 15 6 hours ago, Roland@pcmtec said: You possibly have an oil supply issue then. What pressure are the valve springs? There just the basic crow upgrade spring. Oil is 15w40 and at 4500 rpm have about 50 psi Quote Link to post Share on other sites
Roland@pcmtec 1,525 Posted March 15 Share Posted March 15 It's possible the oil feed to the VCT has been damaged or blocked. I've seen it before. Quote Link to post Share on other sites
Kevspec 0 Posted March 15 Author Share Posted March 15 2 hours ago, Roland@pcmtec said: It's possible the oil feed to the VCT has been damaged or blocked. I've seen it before. I would believe so if under normal loads wouldn't respond but it's only under full load above 4500 rpm everywhere else is fine Quote Link to post Share on other sites
Roland@pcmtec 1,525 Posted March 16 Share Posted March 16 22 hours ago, Kevspec said: I would believe so if under normal loads wouldn't respond but it's only under full load above 4500 rpm everywhere else is fine If you run spring boost pressure only does the problem go away? Quote Link to post Share on other sites
Kevspec 0 Posted March 17 Author Share Posted March 17 2 hours ago, Roland@pcmtec said: If you run spring boost pressure only does the problem go away? No. On low boost 7 psi it holds flat until the cam starts advancing then boost climbs with revs. On high boost 18 psi hold flat from 3000 rpmto 6200 rpm but power drops off aggressive when cam plays up. I am going to swap oil back to original 10w30 as besides turbo only other thing that is the only other thing changed to a 15w40 Quote Link to post Share on other sites
Roland@pcmtec 1,525 Posted March 17 Share Posted March 17 So the cam error is the same on low boost and higher boost? Eg wot run, overlay the cam angle error and see if it's the same. If it's worse on high boost then you likely have an oil supply or actuator problem as the higher the boost the more pressure/gain the actuator needs to shift the cam. Quote Link to post Share on other sites
Kevspec 0 Posted March 17 Author Share Posted March 17 1 hour ago, Roland@pcmtec said: So the cam error is the same on low boost and higher boost? Eg wot run, overlay the cam angle error and see if it's the same. If it's worse on high boost then you likely have an oil supply or actuator problem as the higher the boost the more pressure/gain the actuator needs to shift the cam. 1 hour ago, Roland@pcmtec said: So the cam error is the same on low boost and higher boost? Eg wot run, overlay the cam angle error and see if it's the same. If it's worse on high boost then you likely have an oil supply or actuator problem as the higher the boost the more pressure/gain the actuator needs to shift the cam. Issue is same no matter what boost setting is Quote Link to post Share on other sites
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.