Idle issue - About ready to sell this old girl

[Dprocks100]

I wouldn't even think about replacing the engine when the compression in the "low" cylinder is still at 110psi. If it were like 85psi then sure.

I recommend you replace the intake manifold gasket and keep driving it. Gaskets are cheap and easy to replace so I think it's worth the time.

I did buy a intake gasket set today, should be here by Thursday. I'm not sure if its going on this engine or not, kind of bought it because I would need one for the other engine anyways. I have a little while before I can dive into swapping the engine, so I might go out this weekend and mess around a bit, tighten the intake etc. Honestly, I wouldn't have a problem driving it until it dies or burns too much oil to keep up, if I can get the idle to come down and get it to stop missing. I just don't like the fact that its so much lower than the others. Doesn't that cause even more problems the further away from the others it gets? All the stuff I've read says that there is a serious problem once its past 10-15% than the others and it causes running issues.

 

[Mark_88]

I did buy a intake gasket set today, should be here by Thursday. I'm not sure if its going on this engine or not, kind of bought it because I would need one for the other engine anyways. I have a little while before I can dive into swapping the engine, so I might go out this weekend and mess around a bit, tighten the intake etc. Honestly, I wouldn't have a problem driving it until it dies or burns too much oil to keep up, if I can get the idle to come down and get it to stop missing. I just don't like the fact that its so much lower than the others. Doesn't that cause even more problems the further away from the others it gets? All the stuff I've read says that there is a serious problem once its past 10-15% than the others and it causes running issues.

That's pretty much what I have read over the years...anything over 10% is going to eventually help wear out the other components. It really is a matter of what you can afford, handle (experience) and good fortune at finding an older engine to rebuild...or a newer one to swap.

I think the consensus on the rebuild was to find an older engine from the same year or even the one you have if you can park the truck. Sounds like a simple modification for the crank sensor fit but I've never done one and haven't the resources to even consider it...

I don't think the gasket is that expensive that it would not be worth your while to try it...mostly your time and energy involved but I know how sometimes it is just a really tough call to invest more time in something that is going to be replaced...

 

[Dprocks100]

So I started doing the intake gasket Saturday because I don't think the compression issue is effecting the engine yet. Found a few things that probably have a effect on the way its running currently. First, Fel-Pro gave me the wrong intake gasket when I did the head gasket 6 months ago. The one they gave me covers the coolant passage on the head going to the intake for a 95+, where the new gasket I bought doesn't cover that passage. So the Engine coolant temperature sensor wasn't getting an accurate reading. So I got that all swapped and the lower intake put on. Second issue is while inspecting the injectors, Cyl 3 injector has a small crack. And the other 3 look pretty hammered, so I bought a set of reman injectors. Third issue I found is the vacuum connector for the charcoal canister on the TB is weather cracked. Fourth potential issue is that my brake booster might have a leak. While unplugging the booster line, I heard hissing coming from the vacuum that was stored inside. Sadly, by the point I found that out, the upper intake had been removed, so I wasn't able to test that. Now that I have to wait for my injectors to get here, I won't know if I fixed it until Friday, if I have enough time to finish. I have to work my seasonal job Saturdays now, so I hope I'm able to get it done Friday.

 

[tomw]

While unplugging the booster line, I heard hissing coming from the vacuum that was stored inside.

That should not be a "sadly" condition. The Ranger is made with a 'vacuum reservoir' that will hold enough vacuum to provide power brake boost for ~2 stops after the engine has died in an emergency. It is holding vacuum, so it does not leak. If you had not heard the hiss, your reservoir, the vacuum lines or the check valve would be suspect.
As the engine runs, it forms a partial vacuum in the intake, and that is used to 'vacuum out' the reservoir and all vacuum lines. When the engine stops, the vacuum goes away as air leaks in past the throttle plate. No more vacuum in the intake and in the vacuum lines. The check valve stops air from coming into the reservoir, which is(should be) connected to the power brake booster vacuum connection, thus holding a vacuum(for a while). The HVAC controls that have vacuum motors(positioners0 will also be kept in vacuum if the hoses and controls are in good shape, thus keeping the flaps at the current settings. Defrost is the 'default' mode if vacuum goes away as you can live w/o cool air from the vents or hot air on your feets but you may not live if the windshield is frosted over and you run into a tree...
All that said, good to year you are finding things that should have contributed to indifferent performance. You might find the thing runs so well after all your repairs that you will just run it 'as is' for a few years. The future is hard to predict, especially about things that haven't happened yet...
tom

 

[Dprocks100]

That should not be a "sadly" condition. The Ranger is made with a 'vacuum reservoir' that will hold enough vacuum to provide power brake boost for ~2 stops after the engine has died in an emergency. It is holding vacuum, so it does not leak. If you had not heard the hiss, your reservoir, the vacuum lines or the check valve would be suspect.
tom

I guess I should explain that one a bit better, when moving the check valve around in the brake booster, the built up vacuum was allowed to leak past the rubber seal. I took the check valve out and replaced the seal and the check valve. The seal had a crack and was warn and weather cracked. I don't doubt that helped contribute to my problem with everything else.

So here is the final list of things that were replaced to get this to run right:
All intake gaskets (lower, upper, TB, IAC, EGR)
Injectors + O-Rings
Vacuum lines and connectors
PCV valve and hoses
Brake booster check valve and rubber seal
Cleaned all intake components + IAC valve
Coolant line running behind the head

So somewhere there was a vacuum leak that carb cleaner could not find, I suspect that the lower intake gasket was the most at fault. So far the truck has been running pretty good . Now I just have to get caught up on pre-winter maintenance on it (oil change, tire rotation, fluid checks, put winter gear in the box, etc.) and hopefully it will give me some good service for a while more. Thanks for your help guys!

 

[Mark_88]

Good going...did you check the compression after doing all that work? It might help to know if there is still a major gap...more to simply not push it too hard if possible...not that "I" wouldn't try to put it through the paces...lol

Anyway...thanks for the update...hope it lasts a long time...keep an eye on the oil consumption and also watch for oil smoke between shifts or on startup...that's usually a better indication that it needs a rebuild than just compression numbers...

 

[Dprocks100]

I haven't done another check yet, I kind of don't really want to know. That third cyl has been the problem one. It had the crack when the head cracked, and the injector that was cracked. She doesn't blow any smoke at the moment, and oil consumption actually slowed down after I rebuilt the head. there was a lot of it leaking out of the oil pan gasket and valve cover. I was averaging about 1q every 3,000 miles and I was down 1/2 a quart at 2,000. So hopefully it goes for a bit longer. I guess I'll just have to baby it. I only drive it 5,000 miles a year at the moment, so if it gets me through another year I'd be happy.

 

[tomw]

Quote:I was averaging about 1q every 3,000 miles and I was down 1/2 a quart at 2,000.

FoMoCo won't do anything about a new truck using oil unless it consumes a quart in 600 miles... so, going 3k or 4k w/o using oil is quite good.
tom