misfire nightmare
Ok i understand that but i took the coil and the injector off of cyl 3 today and swapped them with the #1 cyl and same thing happens on #3. Come to find out the mechanic that changed plugs for me a few months ago put a helicoil on #3 plug. Thinking maybe loosing compression.. gonna check tomorrow.
Ok my plan was to do a dry then wet compression check today but weather turned nasty. My one concern is if i do a wet compression check and it tells me i have bad valves that could also mean a leak around the helicoil right? So if so what do you recomend to do? At this point im already thinking pull the head replace valves and reair the plug port properly. Or is there something else i could do?
Ok my plan was to do a dry then wet compression check today but weather turned nasty. My one concern is if i do a wet compression check and it tells me i have bad valves that could also mean a leak around the helicoil right? So if so what do you recomend to do? At this point im already thinking pull the head replace valves and reair the plug port properly. Or is there something else i could do?
Right, - The indicated compression pressures are considered within specification if the lowest reading cylinder is within 75 percent of the highest reading. Refer to the Compression Pressure Limit Chart in my sig.
Here's a TSB, Should help with any questions.
TSB
00-26-1
ENGINE - ROUGH IDLE/MISS AFTER START-UP DURING COLD AMBIENT TEMPERATURES LESS THAN -12 DEGREES C (10 DEGREES F) - VEHICLES BUILT 3/1/1996 THROUGH 7/31/2000
NOISE - FROM ENGINE - ROUGH IDLE/MISS AFTER START-UP DURING COLD AMBIENT TEMPERATURES LESS THAN -12 DEGREES C (10 DEGREES F) - VEHICLES BUILT 3/1/1996 THROUGH 7/31/2000
Publication Date: DECEMBER 8, 2000
FORD: 1997-1999 F-250 LD
1997-2000 ECONOLINE, EXCURSION, EXPEDITION, F-150
1999-2000 F SUPER DUTY
LINCOLN: 1998-1999 NAVIGATOR
ISSUE:
Some vehicles equipped with a 4.6L, 5.4L, or 6.8L engine may exhibit a rough idle/miss after start-up in cold ambient temperatures (less than -12°C/10°F). This may be caused by a roller finger follower(s) being dislodged from the valve. This may result in damage to the camshaft, roller finger follower, valve, retainer, etc. A procedure is now available to service this condition.
ACTION:
Inspect and replace any worn or damaged engine valve components and install new retaining clip and lash adjuster for service. Refer to the following Service Procedure for details.
SERVICE PROCEDURE
Perform normal engine diagnostic routines before opening valve covers. If the valve train is suspect, remove the valve covers and look for Roller Finger Follower(s) (RFF) that may have become dislodged.
Inspect the following parts that may have been damaged by any dislodged roller finger followers:
Cam lobes (chipped or grooved)
Valve stem tips (mushroomed, metal displaced, or bent)
Roller finger followers (chipped or grooved)
Inspect valve guide only if its corresponding RFF or valve stem tip is damaged.
Replace damaged parts as necessary.
If follower(s) are damaged, replaced as necessary, otherwise re-use followers in same location as removed from head.
Remove all intake and exhaust lash adjusters from the engine and replace with service-only Lash Adjusters (YL3Z-6500-AA). Refer to the appropriate Workshop Manual, Section 303-01B for service procedures and tooling necessary to compress the valve springs and remove the roller followers.
NOT:REFER TO FIGURE 1 FOR INSTALLATION OF THE NEW RETAINING CLIPS (YL3Z-6A539-AA), TO THE ROLLER FINGER FOLLOWER.
Using a valve spring compression tool, install followers and the attached retaining clips by pushing clips onto lash adjuster.
NOT:THE CLIP IS NOT REMOVABLE FROM ADJUSTER ONCE IT HAS BEEN SNAPPED INTO PLACE. IF THE ENGINE NEEDS TO BE SERVICED AT A LATER DATE, REMOVE THE RFF BY BENDING UP THE CLIP. LEAVE LASH ADJUSTER IN THE ENGINE WITH THE CLIP WHILE REMOVING THE FOLLOWER. THEN REMOVE THE LASH ADJUSTER FROM THE HEAD AND SNIP/CUT THE CLIP FROM THE LASH ADJUSTER. REPLACE WITH A NEW CLIP ON FOLLOWER DURING INSTALLATION.
Check valve train for proper assembly and reinstall valve covers as outlined in the Workshop Manual, Section 303-01B.
PART NUMBER PART NAME
YL3Z-6A539-AA Retaining Clip - Roller Finger Follower
YL3Z-6500-AA Lash Adjuster
Here is a note on switching from 5w20 to 5w30 for a trial.
The cold starting pressure went to an alarming near 100 psi on a rev above 3000 rpm.
I don't normally do such thing but wanted to see what happens to the pressure.
Hot running normal speeds is about 8 to 12 psi higher depending on RPM which means from 48 psi to about 52 on my readout.
The biggest issue with oil pressure from the heavier oil is the cold startups and the short run times that keep the pressure up before fully heating to normalizied temps.
Oil goes to the heads then through a restrictor and filter to the valve train.
At next change I will go back to 5w20.
This motor has 188,000 miles and quiet as new.
Good luck.
The cold starting pressure went to an alarming near 100 psi on a rev above 3000 rpm.
I don't normally do such thing but wanted to see what happens to the pressure.
Hot running normal speeds is about 8 to 12 psi higher depending on RPM which means from 48 psi to about 52 on my readout.
The biggest issue with oil pressure from the heavier oil is the cold startups and the short run times that keep the pressure up before fully heating to normalizied temps.
Oil goes to the heads then through a restrictor and filter to the valve train.
At next change I will go back to 5w20.
This motor has 188,000 miles and quiet as new.
Good luck.



