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Eric, love the show by the way. Recently my 99 Altima SE 5-speed just 3k miles shy of 200k miles decided to quit on me. I’ve been experiencing some noise around the top end near cylinder number 1. oil light flashing on and off at low idle. low idle meaning normal operating idle never had a problem with idle. didnt seem like i had a dramatic loss of power. until the car decided to die on the bridge and i couldnt get it to turn over again (crank no start). had it towed to the house, went and bought a fuel pressure gauge but couldnt find the Schrader valve for the life of me so i went ahead and replaced the fuel pump anyways. fail. so i had it towed to the shop and they said i have compression loss across all 4 cylinders. i’m very diligent about oil changes and keeping it tuned up via plugs wires fluids and oil treatment. please help me eric
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what i was wondering is could i rebuild the top end but also replace the piston rings? i live on the North West region of the usa and i seem to be having difficulty finding a replacement engine locally. I would rather spend the money on a rebuild kit and fix it myself with the knowledge ive obtained through watching your videos and following the Haynes manual.
When that oil light started flickering, that was your warning sign. That was when you needed to have it looked at, and find out what was going on.
Now, it is well past that point. Low compression across all four cylinders, to the point that the engine won’t run generally means it needs to be replaced, or completely rebuilt. That, combined with the oil light flickering on and off, I would think you are in for doing the bearings, both rod and main, and probably the cam(s) as well, in addition to boring the cylinders out and honing for oversized rings. In all honestly, it will probably cost you more to rebuilt that than it will to buy a rebuilt engine and just swap it in.
Low idle can cause the oil light to flicker. The oil pump will not be able to produce a sufficient volume to keep the light off if the idle is low enough. If you suspect an oil psi problem, the best thing to do is check the actual oil pressure with an oil pressure gauge.
As for the low compression, you might want to do a compression test yourself, or have a second opinion. Besides worn cylinders and rings, low compression can also be the result of improper timing or even a low battery. If you truly want to know what’s going on with an engine, a leak down test is the way to go.
Compression testing
Leak down testing
I don’t recommend rebuilding engines if you find one that’s worn out. I would instead recommend a replacement engine, rebuilt would be best, but a low mileage salvage unit can also work.
In summary, verify that you do indeed have engine damage and if you do, seek out a replacement over rebuilding.
Good luck and keep us posted.
just got my ride back to my garage and i’m ready to start the tear down. i’ve called many sources and the available ka24de engines they have in town are for automatic transmissions. that reason alone led me to make the decision of rebuilding myself. i have the sporty Altima SE edition with a 5-speed transmission.( pretty sure its rare) ive also done work to it myself (cold air, OBX exhaust, and high output alternator for my stereo). as for the compression test i will redo the test because i feel like the mechanic did not do the test correctly. just have go buy a gauge and go from there. ive learned a lot just reading books, my haynes repair manual, and watching eric’s and other videos online. all i’m missing is the hands on experience of tearing an engine apart. i am looking forward to it. i suspect that i will have to replace rings, bearing, and some machine work. well i will keep you updated eric. thank you for making such great videos and sharing your knowledge with the world.
eric!! i started taking apart the engine a little bit. took some stuff apart to take the valve cover off, drained the oil, and removed the splash shields from the bottom. while doing that, i noticed a heavy scent of gasoline in the oil. any idea why?
it is normal for high mileage engines to have wear on the cylinder walls, and the piston rings. As these wear, the gap between the rings, and the cylinder walls gets bigger, allowing an increasing amount of “blow by” to happen. “Blow by” is a quantity of compressed air and gas from your combustion chambers that leaks between the worn rings, and cylinder walls, and manages to get into the crankcase. As this happens, the fuel that is present in the blow by will mix with the oil in the crankcase, making it smell like fuel, and thinning it out some as well.
Usually, there will also be some oil burning in an engine that has that much blow by, and you can usually see some traces of oil in the intake system, just after the PCV hose, as the blow by often pushes oil up through that hose, and into the intake. If you have ever seen a car that seems to burn oil off at higher RPM’s just before shifting to the next gear (high mileage Honda engines are famous for this) that is the effect of blow by pushing oil into the intake system.
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