Ok had my 87 for over a year, have had the usualy 3800 bogging etc. no serious mechanical or electrical issues. Today driving back from work i noticed the tach was jumping around under light highway throttle but the engine wasnt actually revving at all. then i noticed under moderate acceleration the tach would jump around a bit and i would have small dead spots in acceleration at completely random points. then the tach died completely but engine was still running with just a few little dead spots every now and then. parked it for a few hours then went to a meet, on the way home it started doing the same thing again, tach jumping small random dead spots in acceleration like it wasnt getting fuel or spark. Then it actually stalledwhile under decel. i bumped it, i t restarted after a slight hesitation and some throttle. tach was still dead till i turned the key off and back on. Now normally i would trouble shoot this further, but im exhausted and i have only one car to drive to work tomorrow. I checked various electrical connections etc. no obvious issues. plugs and wires are fairly new, fuel filter is new. please any suggestions as to the issue are welcome.
thank you.

 

Have you done anything to the trailing coil lately? Disconnect the plug to the trailing coil which has the Yellow/Blue wire and clean it up and add a little dielectric grease to it and while you're at it do the same for the other plug connected to the trailing coil. If this doesn't help then connect a jumper wire from the black bullet connector of the leading coil to the same connector of the trailing coil and see if this makes the tach behave as it should. Installing this jumper wire will run the tach off of the leading coil rather than the trailing coil as usual and you could use this test as a way to discern if the problem is trailing coil related or tach related.

 

i'll give that a shot thanks. but could that cause the other issue?

 

and no i havent done anything to the trailing coil lately

 

update, just tried to go to work this morning and it started bucking hard (losing spark i'm assuming) tach died early on, then it would lose all power but the engine would still be running and i'd get a burst of normal power. then it started to stall. couldnt get it restarted until i flipped the switch to my fuel pump and cleared it. this is why i assume its lack of spark, engine was flooded. it died twice after i got it restarted, then third time it started and went like nothing happened.

 

Sounds to me like the coil is taking a crap. I had the same issue just before the motor blew. lol. So lets hope that isn't going to happen to you. I'd stop driving the car, replace the coil with a known good and go from there.

 

well i cleaned the trailing and leading connectors and made that jump wire, all seems to be ok, but i dont really trust it... gonna go try driving to work again.

 

well, fixed it. wasnt the coils or anything. wires were loose on my fuel cut switch.soldered them and it works better than ever now. plus a contact screw was loose. thanks for the help!