I bought a 1990 Accord LX Coupe w/ 69,xxx mi. on the odometer.

The engine / motor mounts seems to be worn, the car / engine vibrates at highway speed around 2500-3000 rpm, once above 3000 rpm the vibe seems to go away.
It got bad enough that during an slight incline @ about 55-60 mph, engine reving at around 2000 rpm, the check engine light came on.

Car has new distributor, new cap, new wires and sparkplugs. Seem to have difficulty starting once the engine is warmed up after good amount of driving. Is that the main relay acting up? or should I replace the motor mounts?

 

Really, no one has suggestions?

 

Well no offense but your description of your symptoms are still a bit vague for anyone to give you a good suggestion.

What is the CEL telling you? (Meaning have you checked to see if anything shows up)

Are you the original owner? The miles are obviously VERY low for a car it's age so there are probably some things that are just worn out from lack of use. Any other maintenance done that might be relevant?

What is your tire maintenance schedule like? (replacing, alignment, etc.)

Has the car been sitting for a while?

 

What is CEL?

No, I'm not the original owner, I just bought this Accord because of the low mileage.

Car sat most of its life in grandma's garage in FL.

Tires/alignment seem ok.

All other maintenance are up to date.

 

CEL = Check Engine Light

Well from knowing that history there are some things that you should really go through and replace because of their age. Sometimes low miles means that you can have extra liabilities because the lack of use.

Timing belt/water pump, check/replace any rotting/damaged serpentine belts, air filter (if dirty), oil change (if not done already), make sure the gas is relatively new, make sure the tires are not too old (they can rot, even if the tread is good, they doesn't mean the tires themselves are).

That's a decent start. You should really try to find what the CEL is, as that SHOULD tell you right away what's wrong.

Until then I can only make guesses. The hard starting when the engine is warm is typically ignition or fuel pump (see relay as well) though you seem to have your ignition up to date. Could be that the starter is having issues with the heat, you could always get it tested. However, before doing anything like that, check for CEL's.

 

It's now seven yeas since i bought my Accord.

Currently have 169xxx miles on the car. A/C has some massive leak that refilling the freon only gives me about 2 days of cold air.

Car still drives fine, tailpipe rattles when it's in reverse.

Detent cable was damaged when local mechanic routed it incorrectly while replacing a radiator hose... now I get heat even when the temperature adjustment is all the way to cold.

I keep it as a winter car, drive it every few days... or just on my 130 miles one-way commute.

Still love this car, will drive it to the ground now that it has antique plate and no need for annual state inspect.