Loss of power, low compression

[rreedican]

(I had originally posted this in the engine forum, but was this may be a better direction)
Hello, I just registered today and ran through many pages of forum to see if I could remedy the problem without asking, but I could not. I have a '79 that was in wonderful (body) condition when I bought it. This is my first car, and the oil pressure-and thus the horsepower-is very low, and living on a hill makes it very difficult to even get into my parking space. What are some possible causes? Should I be checking the fuel pressure next?

Notes:

• Compression [1- 110 2-115 3-110 4-110 5-105 6-85(!)]
• Tested for vacuum leaks, none found
• Ignition timing reset, and found little difference
• Removed O2 sensor to check for back pressure. No difference with O2 out
• Spark plugs look okay

This list was compiled by three separate mechanics for me. I am not interested in spending any more money on not getting this fixed.
Thank you for your time.

[maximaj30]

if your gauge is reading correctly and your oil pressure is low your oil pump might be going bad

[79'SupraKid]

If the oil pressure is low you could be riding the bearings down... and yes that will cause loss of power along with your uneven compression that 6th cylinder is right at the acceptable limit.

[tyrantfour]

low compression in just one cylinder i would look at the head casket or valves first.

[4SFED]

the oil pressure-and thus the horsepower-is very low

Cause and effect? no, that's like the greenhorn who went to a shop with a burned out brakelight and the mechanic convinced him he therefore needed new brakes.

and living on a hill makes it very difficult to even get into my parking space.

That must be one steep hill!

What are some possible causes?

For low oil pressure? For difficulty getting into your parking space?

Should I be checking the fuel pressure next?

no

Compression [1- 110 2-115 3-110 4-110 5-105 6-85(!)]

I've had several mk1's over the years and more than one BHG. It always seems to start with loss of power and cylinder#6 dropping off in compression compared to the rest. I agree with Tyrant above.

I am not interested in spending any more money on not getting this fixed.
Thank you for your time.

You're a funny guy.

[4SFED]

Don't get me wrong regarding low oilpressure - if it's too low yes you have a problem and ultimately the engine may seize up but your post makes it sound like when oil pressure is low you automatically lose hp.
BTW, Tyrant meant gasket not casket.

[CarlH]

Comp testing,, 1)Motor must be hot/ warm. 2) all spark plugs out, 3) Throttle wide open, 4) crank over motor thru at least 6 comp strokes, It pays to watch the rise on the first several strokes.

carb Or injected. ?? I would check fuel pressure and volume . If you have a carb it could be plugged up jets, Injectors may also be bad. Is the gas fresh?

Does the timing advance as motor is reved?? Is the cat or exhaust plugged up??


Notes:

• Compression [1- 110 2-115 3-110 4-110 5-105 6-85(!)]
• Tested for vacuum leaks, none found
• Ignition timing reset, and found little difference
• Removed O2 sensor to check for back pressure. No difference with O2 out
• Spark plugs look okay

This list was compiled by three separate mechanics for me. I am not interested in spending any more money on not getting this fixed.
Thank you for your time.[/QUOTE]

[rreedican]

Tyrant, maximaj, and fsfed-
Thank you for the info. I appreciate your guys' input. The next time I take it to the garage (probably this weekend) I will look at the oil pump, the head gasket, and the valves.

Now about the hill: The problem is, it is not that big of a hill. At it's worst, it is at worst a 6% grade, and killing it and having to coast backwards into someone else's spot is super embarrassing, especially when they tap on your window to ask if they could help, seeing the stick shift, and then wishing me good luck.

[4SFED]

downshift and keep it in low gear when going up the steep grade.