92 Loyale with EA82

 

What is the RPMs speed for optimum mileage? Where do the HP and torque curves intersect?

 

What is the final front axle ratio?

 

I have rough idle, am I correct in thinking that it is probably the EGR valve which hasn't been touched in 185K miles? How often should it be replaced/cleaned?

 

Oxygen sensor - how often does that get replaced? I have an original one, as far as I know. I heard one estimate that O2 sensors get lazy after 80K miles.

It still gets close to 30mpg, but can it do better? I typically cruise at 3300 RPMs, which means 55-60 mph.

O2 sensor - I change mine every 30,000 miles. This may correct your rough idle. Check your plugs and make sure they are not fowled up, replace the PCV valve, air fliter, fuel fliter. Basic maintinence will help idle and gas MPG a lot. I think the axle ratio is 3.70 or somthing like that. EGR valve is not often the problem, they don't hardley ever go bad.

Ever 30,000? that's religious change.

 

I will replace mine. It doesn't seem to run that rich, about 29mpg, but I think it can do better than that.

is it a manual or auto.

for a manual, the best cruising rpm is around 3500 rpm. the motor is fat in its power curve, and takes little pedal effort to maintain or accelerate from there.

3500 rpm on a 5spd dual range with a 3.9 gear is roughly between 55 and 60 mph.

a single range 5spd goes about 65 at 3500 rpm in 5th gear.

 

the motor is happiest at 3500 rpm if you need to accelerate, but a lower cruising speed is good around 3000, but you will need to get more into the gas to pick up speed from there.

 

torque and horsepower curves meet at 5252 rpm, which is true for any motor(its a mathmatical equation that equals out to that)

It is a 3-speed auto. I usually keep it at 3100 rpms.