08 F-250 5.4 VVT Problem when warm
#1
08 F-250 5.4 VVT Problem when warm
2008 Ford F-250 Setting both cam position sensor codes and both VVT PO12 and PO22 Codes. Runs good for a few minutes cold then goes to making noise and retards timing when warms up . Replaced both cam phasers and 1 vct solenoid and camshaft position sensors, changed oil and filter with motorcraft.. Tried unplugging VCT solenoids but still runs bad when warms up. Ran bad when engine was cold or hot before replaced phasers now only when warms up. Does any one have a trouble tree to run for this problem? Is it a oil pressure problem pressure shows good on dash gage Thanks Mike <MIKE< p>
#2
There are updated VCT solenoids for this problem. The part number is 8L3Z-6M280-B make sure you installed this solenoid. Also check the crankshaft endplay and hook up a mechanical oil pressure gauge to the oil sender port. The gauge is just on/off and doesn't actually measure pressure. When you replaced the phasers did you replace the chain tensioners too? They are bad for the gasket blowing out bleeding off pressure.
#3
Installed manual oil pressure gage 60 to 70 psi cold. After running 10 minutes it flucuates between 5 to 40 #s. And engine gets noisy from front timing area. Engine is quiet and runs fine till warms up. We replaced cam phasers. Did not pull timing cover to replace phasers. Could it be bad tensioner or leaking at gasket like U said causing this problem?
#4
The oil pressure fluctuates between 5 and 40 psi when hot? That is a wide range and the low pressure is causing the VCT noise. I would change the oil and use a motorcraft filter with 5w20 oil and retest. If still low then check the crankshaft endplay, should be less than .020". You may have a oil pump that is going out. I don't think a leaking chain tensioner will bleed off enough pressure to only get 5psi at the sender port.
#5
#7
You will need both new updated solenoids. I would also check the tensioners, especially if you hear noise in the cover area. Also I would pull the valve covers and check all the camshaft caps for scoring. Ifit has excessive scoring, IE, if you can catch you fingernail on grooves, then your heads are too far gone.
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#8
2008 cam phasers
Replaced Cam phasers, timing chains, guide plates, tensioners and oil pump. When truck warms up still starts retarding timing and running bad and dieing. Oil pressure bounces fast between 10 and 50 now . Had more power cold but overretards timing when warms up and get real noisy. Replaced 1 solenoid on the noisest side did not help.
Last edited by parauto; 04-16-2013 at 10:12 AM. Reason: added info
#9
This sounds exactly like my truck. I only tried to replace the VCT solenoids. It did nothing. I pulled the valve cover again and the drives side cam caps are scored. I was told that the heads are not rebuildable as there are no bearing surfaces to replace. Cam is even scored up pretty bad. So it is either a new motor or at least heads depending on the mains.
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250RangerJman
1967 - 1972 F-100 & Larger F-Series Trucks
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09-16-2010 04:24 PM