Sticking valves
Hi, I'm fairly sure the valves are sticking in the guides on one cylinder. I've tried Liqui-moly and redex additives with no luck.in the fuel.
Is there anything pls that might go in the oil or fuel to unstick the valves even for a short while. To prove what the fault is
Sticking valves.
Really I made a mistake with the description, it is partially sticking. They move but drag in a sticky motion. Probably.
I videod the movement so all move but I cannot slow it to a speed the eye can diagnose a delay.
The compression is very good but a vacuum check indicates something on one cylinder.
Again the vehicle is of no financial worth so I'm trying to save it without unsensible spending.
With all the gdi problems thi s is something an owner on here will have cured. I hope...
You mentioned this being a GDI engine.
With GDI (Gasoline Direct Injection) engines the fuel is injected directly into the combustion chamber, the only thing flowing past the valves is air, no fuel additive will have any impact on dirty valves, you'll need to use something that is introduced into the intake air stream, and if your valves are dirty enough to be sticking, which as you know, I doubt, then, they are beyond what can be removed by the use of chemical treatment.
Syndicate
Color me sceptic.
Assuming the vehicle hasn't been laid up for a long period of time, the probability of valves being stuck is slim to non-existent.
Now, so that this pellucidly clear I HAVE seen it happen, an older pushrod engine (Morris Garages B-series), parked for several years, the valves that were open when it was parked stuck open and didn't close.
We're not dealing with a B-series here, and whilst you haven't given us any detail as to what engine we're discussing, it's presumably a Mitsubishi, nad since we're discussing an iO (this is an iO forum), most likely a 4G93 or a 4G94.
Let's say you have a valve that IS stuck open, what's going to happen when the engine turns over, this is, what is known as an interference engine, piston meets valve, valve bends.
A compression test will reveal the possibilty of stuck (bent) valves, and a leak down test will confirm it.