Mystery Problems '99 3.0l

[Shockwave86]

Hello all!
I have been working on my dad's Ranger on and off for a month. It was in bad shape when he got it.
Insanity bad shake at startup and would never go away. Shaking would increase from 50mph and decrease at 60. AC doesn't work, coolant temp sensor code won't let the PCM activate the compressor. Slow and sluggish. Finally multiple exhaust leaks at the manifolds.
What has been fixed and replaced:
Sparkplugs
Sparkplug wires
Coil
Injectors (6)
Thermostat
Coolant temp sensor and sender
Camshaft position sensor
Crankshaft position sensor
EGR tube and valve
MAF has been cleaned
Engine mount (driver side)
Heads have been replaced with remans

Dad's Ranger is running much from when he got it due to all the work but there are problems now that I can't figure out:
Truck needs to crank for a few seconds before it will start
Engine shake
2ish misses and no codes from those misfires. Misfires will start when cold but reduce or go away when warmed up. Misfires do return when reving.

I haven't checked the sparkplugs yet to find which cylinders are misfiring. I suspect fuel injectors.
The only code that pops up is for the coolant temp sensor.
I appreciate any suggestions on what my problems are.

 

[Curious Hound]

Are you sure you got the cam position sensor timed properly?

 

[Shockwave86]

Are you sure you got the cam position sensor timed properly?

I am 100% sure it's timed properly.
I've been thinking it might be a PCM problem.

 

[pjtoledo]

is it flex fuel?
did you run a compression test?
what is the fuel pressure? don't see fuel filter on your list.
double check the plug wires.
what's the oil pressure? maybe a lifter is not pumping up.
if you have access to an infra red thermometer look at the individual exhaust runners.

before starting, cycle the key several times. the fuel pump will build pressure on each cycle. then try starting.

to isolate no-fuel at idle, rig up a way to inject some flammable fluid into the intake. NOT ON THE MAF.
if the idle smooths out the spray is getting into a cylinder not fed by a bad injector.

 

[Shockwave86]

is it flex fuel?
did you run a compression test?
what is the fuel pressure? don't see fuel filter on your list.
double check the plug wires.
what's the oil pressure? maybe a lifter is not pumping up.
if you have access to an infra red thermometer look at the individual exhaust runners.

before starting, cycle the key several times. the fuel pump will build pressure on each cycle. then try starting.

to isolate no-fuel at idle, rig up a way to inject some flammable fluid into the intake. NOT ON THE MAF.
if the idle smooths out the spray is getting into a cylinder not fed by a bad injector.

It is a Fex.
I have not done a compression test on the new heads yet.
I did put a new fuel filter on, idk what the fuel pressure is.
I'll check the spark wires again.
I haven't checked the oil pressure, I'll definitely keep the lifters in mind.
I don't have an infrared thermometer.

I'll definitely try cycling the key.
I'll be trying the spray method too.

 

[Shockwave86]

*Update!
I haven't done any of the testing yet, but dad and I turned it on for a few and we found something:
Backfiring into the intake.

We suspect it's the remaned heads.

 

[pjtoledo]

that's also classic timing problem symptoms.

ok, new heads were put on.
did you check the valve lash when tightening the rockers????

3.0 valve train parts are supposed to be tolerant enough to just bolt it on and go.

however, when tightening the rockers pay attention to when the push rod tenses up, then how many more turns on the rocker bolt until tight.

 

[Shockwave86]

I was not aware about the valve lash. I did bolt just bolt on the rockers on tight (not gorilla tight) and thought nothing of it.
I did not pay attention to when the push rods tensed up.
Is there a specific spec the rockers are supposed to be at?

 

[pjtoledo]

proper torque for that bolt is all. 24 ftlbs.
valve lash is determined by how much the lifters collapse during installation. there is a plunger inside the lifter that moves.
they work in an equilibrium state where the oil pressure pumping them up is countered by the valve spring pressure, and
the bleed-off going up thru the pushrod. they need to be collapsed some, about 1 or 1-1/2 turns, but not bottomed out.

when reman parts are introduced you don't know what the new tolerances are so the lash (collapse) should be checked.

 

[Shockwave86]

Update
GOOD NEWS!!!
I found the backfire problem. #3 intake valve. I loosened it by half a turn. I also loosened every rocker by 1/8 turn.
The engine runs SO good now.

But, I have another mystery.
The engine shakes and there is a squeaking noise at the back of the engine. The noise goes away or dampens a lot when taken out of park. Dad and I think the flywheel might be warped or cracked, or the transmission isn't bolted on tightly.

 

[Curious Hound]

Squeak near the rear of the engine is usually the cam position synchronized. The upper bushing isn't lubricated. So it eventually fails. It's often accompanied by a worn drive gear. So, replacement is recommended.

 

[Bgunner]

Squeak near the rear of the engine is usually the cam position synchronized. The upper bushing isn't lubricated. So it eventually fails. It's often accompanied by a worn drive gear. So, replacement is recommended.

I was going to say the same thing. You just beat me to it.

This is a common failure point on all 3.0L engines including the ones with distributors. When they start to go they sound like a belt chirping but when they get really bad they have a metal on metal screech to them at times. Once you hear any of this it is best to stop running it and change the Distributor/Synchronizer or it will take out the cam gear and then you are into a rebuild of the engine.

Here is a link to the tech section about the synchronizer issue and replacement: https://www.therangerstation.com/tech/3-0l-camshaft-position-sensor-synchronizer/

 

[Shockwave86]

It's been a while and most of the problems have been fixed.
A vacuum leak was causing the hard starting.
ALL the bell housing bolts on the drivers side were gone. That is what was causing the horrible shake.
I also replaced all the lifters. That fixed all the misfiring.
The flex plate, rear main seal, and torque converter were changed too.
Adding new transmission fluid, predicably, broke the transmission. I did suggest first to have the transmission completely rebuilt before it broke the second time, dad wanted just the transmission pump replaced.
Dad's ranger is running good now. Thanks everyone for the help!