It's a 92 Royale 4WD 3AT 1.8L [H4 MFI/FI <--- what's all this mean?]
At 35mph it starts a horrible ticking, at 45mph it starts going faster and 50mph
and above it get so fast it becomes a hum. Any idea what it is and how I can fix it?
I found this on another Forum, but I can't find the forum again
Also, it idles terribly rough. It looks like a wet dog trying to dry off. Any hints there?
Is it the timing that needs adjustment?
Whew! First off, you have a Loyale, not a "Royale". This is the name for the later GL/DL models - basically the same car with some upgrades to the engine fuel management and such.
As for "4WD 3AT 1.8L [H4 MFI/FI": Four wheel drive, three speed automatic, 1800cc displacement, Boxer-four cylinder arrangement (just like an old VW), MPFI is multi-port fuel injection, FI would likely be single-port fuel injection (SPFI).
You have the classic "Tick of Death". I'm going to repeat your quoted bit:
"hydraulic valve lash adjusters (aka HVLA or HLA) get dirty.
You might try sea foam or MMO in the oil for a couple hundred miles then change the oil.
This is supposed to work pretty well. You can get Seafoam from AutoZone etc. Basically part of your valvetrain is a bit clogged. Seafoam can clear stuff out. I've never had to fix this, but others on the board can perhaps offer good advice. It's been covered about 30 times in different threads, do a search for "tick of death".
Questions to help narrow down your particular problem:
1) How many miles on the car/engine?
2) How's the oil level? Full? Dropping out the bottom of the engine? Rough idle as you describe can be due to something as simple as not enough oil in the engine. Make sure it's reading properly at the dipstick, and that your oil pressure gauge (if you have one) is reading decently.
Let us know more about these things and we may be able to help... good luck!
P.S. Add your city to your profile if you like... there are lots of us in Eugene and Portland and sometimes we can give location-specific info about shops, parts sources etc... :cool: