First off, '87s are subject to wiring harness problems. Is yours in good shape or can you see bare copper or crumbling insulation anywhere? If so, it's possible that nothing is going to work.

IF it's ok, first check the plugs and make sure none are fouled. If it's been a while, replace them anyway, they're less than $2 each. Same goes for a dirty distributor cap or a burnt up rotor- easy to check, easy to replace.

There could be a significant vacuum leak. Look at the black hose to the air mass meter. Is this the "air housign" that was replaced? IF it has any holes in it, replace it. It's possible that the intake manifold gasket or the fuel injector seals are leaking. A shot of carb cleaner on each point should reveal any leaks- idle will increase if there's an air leak there.

You could have a fuel pressure problem. It's hard to say if it's too high or too low without a pressure test, but your mechanic can check the mixture on an exhaust gas analyzer (should be a standard tune-up test, not very expnsive) and if he finds that it's way off it should be checked. You could have a bad Fuel Pressure Regulator, which will throw the mixture way off.

Good luck!
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Rob Bareiss, New London CT ::: "Roterande Fläkt Och Drivremmar!"