I acquired a beat-half-to-death 95 LE with 160K miles on it; the windshield is even scratched from not having any wiper blades, the prior owner took such bad care of it! Anyway, I'm still having trouble getting the engine in shape, and want advice as to which step to take next.

First, though, I've: installed new plugs, wires, distributor cap, changed all the fluids, changed air filter, cleaned the throttle body and IAC, checked the AC idle-up valve, looked for vacuum leaks, and a couple other things. I even fiddled with the throttle position sensor (good try, JohnnyUK), but to no avail. The engine still doesn't have any torque (especially if the AC is on) to handle hills, and the oil pressure light routinely blinks on intermittantly or comes on steadily when the car is in gear at a stoplight....

Idle speed looks correct, and the car performs great at speed (i.e., when the torque demand is reduced). So, in what order should I consider the following DIY projects?

• Replace fuel filter
• Remove oil pan and check the oil screen for contaminants, etc.
• Pay to have a compression check done
• Pay for a vacuum leak check
• Other???

I am a relative novice at this stuff, although I've been able to wrench quite a few basic things over the past 1 1/2 years. Just trying to play the percentages and save a few dollars if possible. Any help is appreciated.

 

If the engine idles OK doubt if there is a vacuum leak.

Crank the engine over with the ignition system disconnected. Determine by sound if one or more cylinders has very low compression. If so the cranking speed will increase as the cylinder with low compression is pressured during its compression stroke.

Does the engine miss under load, etc?

Have you tried down shifting manually to increase engine RPM when going up hills? Determine if the engine has no power or the trans is not downshifting to raise the RPM.

Typically the can fuel filter in the engine compartment seldom plugs up. However if the engine has no power might be worth changing. If attempting this use a tube wrench and also hold the filter can to prevent it from rotating. The fuel fittings to the filter can be VERY tight and VERY difficult to break free. More then one person has rounded off the tube fitting lobes or twisted the fuel line attempting to break the fittings free.

You may be able to rent a compression tester. 178 psi or more, 142 psi minimum, difference between cylinders 14 psi. Remove all plugs, throttle fully open.

Engine compression can be lower then minimum, say 110, 120 psi if the cylinders are reasonably uniform.

You can remove the oil pressure switch and replace with gauge. Minimum pressure at idle is 4.3 psi, 36-71 psi at 3500 rpm.

If low oil pressure could be worn main bearings, engine sludge, plugged up engine intake screen, stuck open oil pump bypass valve.