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Andyman · 06-08-2008, 02:35 PM

I think something may not be adjusted quite right on your car. Or maybe you have to stop or slow down too much during your driving. I have an '88 Accord too. Mine has fuel injection and automatic transmission. On a recent highway trip of 276 miles (until I filled the tank) I averaged 38 MPG. Mostly I was going about 55-65 MPH but some of the time I was travelling on roads with a red traffic light every few miles. According to the EPA, your car should get about 4 more miles per gallon on the highway than mine.

I found a few things that needed attention on my car. The timing belt was a little loose. After I adjusted the tensioner, a slight knock at full throttle and low speed went away. My distributor advance mechanisms weren't working. The centrifugal advance was stuck but I got it working by spraying WD-40 into the bottom of the distributor and then putting the rotor back on and twisting it several times. The vacuum advance didn't work either. My distributor has two diaphrams and two vacuum hoses on it. The inner hose (closer to the center of the distributor) is connected directly to the intake manifold and the outer hose connects to a vaccuum switch which connects to manifold vacuum when the engine is cold for some additional spark advance. My outer diaphram seems to have a leak and it caused all vacuum advance to go away after the engine was warmed up. By clogging the outer hose with a piece of fat wire, I was able to restore normal vacuum advance for warm operation. I noticed more engine power at light throttle after that. I also suggest that you check for dragging brakes and the front and rear wheel alignment. I like to check alignment by pushing the car with the engine off and checking the bulge at the bottom of each tire to see if it changes depending on whether the car was pushed forwards or backwards. Use a ruler to check how far the tire sticks out beyond the rim for good accuracy. If the bulge gets bigger when you push the car forwards then you have toe out. If it gets smaller then you have toe in. The goal is to adjust your alignment until the bulge is the same when you push the car forwards or backwards. Correct Ignition timing is very important for good fuel economy. You may be able to advance it a little (probably no more than 4 degrees) from the specified setting for better efficiency without knocking. If you get some knocking, just retard it a couple of degrees.

06-08-2008, 02:35 PM	#10 (permalink)
Andyman amateur mech. engineer Join Date: May 2008 Location: New York City Posts: 112 Sporty Accord - '88 Honda Accord LX-i 90 day: 23.25 mpg (US) Dad's Camry - '01 Toyota Camry CE 90 day: 22.81 mpg (US) Artie's Camry - '98 Toyota Camry 90 day: 37.3 mpg (US) Thanks: 0 Thanked 17 Times in 4 Posts	I think something may not be adjusted quite right on your car. Or maybe you have to stop or slow down too much during your driving. I have an '88 Accord too. Mine has fuel injection and automatic transmission. On a recent highway trip of 276 miles (until I filled the tank) I averaged 38 MPG. Mostly I was going about 55-65 MPH but some of the time I was travelling on roads with a red traffic light every few miles. According to the EPA, your car should get about 4 more miles per gallon on the highway than mine. I found a few things that needed attention on my car. The timing belt was a little loose. After I adjusted the tensioner, a slight knock at full throttle and low speed went away. My distributor advance mechanisms weren't working. The centrifugal advance was stuck but I got it working by spraying WD-40 into the bottom of the distributor and then putting the rotor back on and twisting it several times. The vacuum advance didn't work either. My distributor has two diaphrams and two vacuum hoses on it. The inner hose (closer to the center of the distributor) is connected directly to the intake manifold and the outer hose connects to a vaccuum switch which connects to manifold vacuum when the engine is cold for some additional spark advance. My outer diaphram seems to have a leak and it caused all vacuum advance to go away after the engine was warmed up. By clogging the outer hose with a piece of fat wire, I was able to restore normal vacuum advance for warm operation. I noticed more engine power at light throttle after that. I also suggest that you check for dragging brakes and the front and rear wheel alignment. I like to check alignment by pushing the car with the engine off and checking the bulge at the bottom of each tire to see if it changes depending on whether the car was pushed forwards or backwards. Use a ruler to check how far the tire sticks out beyond the rim for good accuracy. If the bulge gets bigger when you push the car forwards then you have toe out. If it gets smaller then you have toe in. The goal is to adjust your alignment until the bulge is the same when you push the car forwards or backwards. Correct Ignition timing is very important for good fuel economy. You may be able to advance it a little (probably no more than 4 degrees) from the specified setting for better efficiency without knocking. If you get some knocking, just retard it a couple of degrees.