Check engine light flashes on acceleration

:banghead: I've got a 1991 geo metro, 3 cylinder, & check engine light flashes on acceleration it seems. Had the car about 4 years, automatic transmission. It also idles rough after it warms up. Dies sometimes at stops or when putting in reverse. Pulled dash out saturday & discovered check engine light missing along with 2 others. Its been a good car, usually gets 40 mpg. Paid $600 for it. Anyone out there had same problem? Also have 1994 geo 5 speed. Love it. Got 57 mpg last summer. It still gets over 50 mpg and needs rings.

make sure you don't have the diagnostic fuse plugged into the fuse box. its the one toward the firewall in the fusbox under dash. it sits a little lower that the rest. if you have the plastic fuse cover you will see the slot in it where it plugs in. if you don't have it plugged in you might want to pulg it in and see what code is coming up. do a search on how to read them

I've checked code & reset twice, different code each time, still flashing & eventually will get codes. Last time got 3 codes, O2 senser, EGR, & Intake Air Temp......will reset & try again, see what get. Saturday discovered distributor rotor centrifical advance locked in place, cleaned & lubed, can set timing right now.

Try checking your vacuum lines. If it is only happening on accelleration, you might have started developing a vacuum leak. Reseat all the connections (this will also reveal the ones that are dry rotted) and see if the problem still happens.

:grinyes: Reringed & revalved my 1991 metro. Found problem, intake valve had a hole/crack in it. Problem solved, running fine. Getting 41 mpg, has automatic transmission in it. Hope this can help someone else.

Whick intake valve? Do you mean the throttle valve in the intake manifold?
Do you have a carburator or fuel injection?

It was an intake valve in the head.....Engine check light flashed again for awhile & then stayed on.....haven't checked the code yet.