Valve issue?

[ecgreen]

I am still chugging along in my spare time on my 89 BII. It looks as if I have solved the oil in the coolant problem, but it is still running rough. Here is where I am at:

- The engine idles at a regular RPM, but sometimes it is a bit high when cold. When its warmed up, its happy.
- It seems like there is a misfire. The engine shakes a bit and it feels like it misses on acceleration sometimes. It also has a somewhat loud exhaust even after I had a reputable company go through the exhaust and look for leaks. As a result I can feel I am not getting full power.
- On acceleration, the engine will have very brief periodic hesitations. They are most noticeable between 2000 and 3000 RPMs.
- There is some sort of clatter sound between 2000 and 3000 RPMs as well. It sounds like valves to me, but I am not sure. Sometimes I can get the engine to not do this if I floor it.
- Air coming out of exhaust is pulsating (for lack of a better word). If I hold a piece of paper up to the tailpipe, it flutters back and forth.
- I have a strange smell I can't quite put my finger on. Its not pure exhaust or fuel smell, but its there when I am driving. I know it sounds weird, but whenever I drive this truck, my eyes get dry in the cab.

Here is what I have fixed and /or ruled out:
- All new vac hoses
- IAC cleaned and tested
- New MAP sensor
- New Motorcraft plugs and wire
- TPS tested good
- Holding good vacuum (measured with gauge)
- Compression is reasonable on all cyls
- Fuel pressure is good, checked with a gauge.
- Tested FPR and its working fine
- Used the screwdriver method to check if injectors are working and they all are.
- Re-did the timing 100000000 times

My thought is that it is a stuck exhaust valve, but I am not sure how to diagnose that.

Thoughts for the gurus?

 

[ecgreen]

 

[ecgreen]

Pulled the valve covers off today and all the valves seem to be going up and down just fine, so nothing seems to be stuck. I initially thought it was a stuck valve. Next I am going to try putting some air through the spark plug hole with the tension taken off the rocker to see if air come out the intake (or elsewhere)

 

[ecgreen]

Now I am thinking timing chain...

 

[gaz]

It sounds like you have at least 3 issues, just resolve one at a time; a misfire, funny smell and valve train noise.

When you do that air test, the place you want to see the air exit is through the valve guides. If it exits through the valve guides, then they are trashed.

This is a good time to pull engine codes.

For your misfire, suspect your ignition module or a failing coil. If it were caused by your injectors, rebuilding and cleaning them is simple and pretty cheap.

In regards to the smell, is coolant leaking into your cab from the heater core?

Since you have the valve covers off, pull your rocker arms. Dissasemble and thoroughly clean the the shafts. Take look at the push rods, rockers and lifters for proper condition and operation. When you reasemble this check to verify that the correct preload is felt by those hydraulic lifters. If these components are still serviceable, when cleaned and resembled at the proper preload, you shouldn't have any valve train noise.

 

[bcschief]

Compression test and a cylinder leak down test will tell you the condition of the engine. Check with your local Autozone for a compression test gauge on their rental tool program. It will cost you nothing after you return it. As far as a cylinder leak down tester you maybe able to borrow one from somebody. There are plenty of video's on U tube on how to perform these test. I would do this before spending another dime on this engine.

 

[ecgreen]

Compression tests are normal.

Well, I re-did the initial timing an 80% of the problems went away. Power is back, hesitations are minimal and seeming misfire is gone. Engine shake is also minimal now, probably due to 30YO engine mounts.

I still have some sort of exhaust leak and I think its the pass side manifold.

There is also still a rattle sound from 2000 to 3000 RPMs. I am at a loss as to what it might be.

 

[Nez'sRanger]

Yeah, that rattle at 2500 rpm... Sheesh! I have it in mine. Drives me nuts, but I've put on 8,000 miles on it so far; no rods thrown, rings blown, and no valves have exploded, yet. I've redid the valve lashing to no avail. Must be a bottom end issue?

 

[ecgreen]

Yeah, that rattle at 2500 rpm... Sheesh! I have it in mine. Drives me nuts, but I've put on 8,000 miles on it so far; no rods thrown, rings blown, and no valves have exploded, yet. I've redid the valve lashing to no avail. Must be a bottom end issue?

You got me! lol

 

[rusty ol ranger]

Sure its not spark knock?

For shits n giggles run 93 in it with some octane boost see if it changes.

Could be a simple vaccuum leak causing a lean condition.

 

[ecgreen]

Sure its not spark knock?

For shits n giggles run 93 in it with some octane boost see if it changes.

Could be a simple vaccuum leak causing a lean condition.

I tried the 93 thing and no luck. Also changed every vacuum hose on the thing, as well as various gaskets. The only one I haven't touched is the throttle body gasket. I'll change it for poops and giggles.

 

[rusty ol ranger]

I tried the 93 thing and no luck. Also changed every vacuum hose on the thing, as well as various gaskets. The only one I haven't touched is the throttle body gasket. I'll change it for poops and giggles.

TB gasket shouldnt make that big of a difference.

Upper intake gasket get changed?

Being an 89 you dont have EGR or a knock sensor. You sure its the engine?

 

[ecgreen]

TB gasket shouldnt make that big of a difference.

Upper intake gasket get changed?

Being an 89 you dont have EGR or a knock sensor. You sure its the engine?

both lower and upper intake gasket changed. No EGR. Actually, I am not 100percent sure it's the engine. Just not sure where to look next

 

[gaz]

ecg:

NOISE; did you clean the rocker arms when you had them open and subsequently, verify that your lifter preload is correct?

MISFIRE:
- did you measure the resistance of and check the output voltage from your coil?

- if your coil is verified working at 100% and your ignition module is not dying, then you should consider cleaning your injectors