1994 Chevy Lumina Engine miss

1994 CHEVROLET LUMINA

103,000 MILES • 6 CYL • FWD • AUTOMATIC

DAVID FISHER

MEMBER
1 POST

Had tune-up done. Plugs, wires, oxgen sensor, fuel filter, etc. At cold idle engine misses but not badly. Starts good but can hear an intermittent poom-poom sound through the exhaust. It gets better after it's warmed up.My mechanic replaced a plug and cleaned the egr valve. The miss is still there. The miss is much more pronounced when I hit the gas hard pulling up a hill especially when it's cold. He says I need to replace the egr. I think it's a bad or partially clogged injector or maybe the idle air control valve. Your thoughts?

Mar 10, 2008 at 9:10 AM

MASTERTECHTIM

✓Experienced Mechanic
4,750 POSTS

sounds to me like either carbon build up on the valves or injector, there is a high pressure injector cleaner that will unplug injectors and eliminate a carbon problem. egr cant be the problem if it does it under hard acceleration. get back to us and let us knowhow you make out. also is the check engine light coming on?

Mar 10, 2008 at 9:59 AM

BLACKOP555

✓Experienced Mechanic
10,386 POSTS

USER REPLY:

replied in topic: http://2carpros.com/forum/here-vp224121.html#224121

stated: " Check engine light comes on ONLY at high speed on the interstate ---- never while driving around town. This occurs mostly when I let up on the gas going down hill. Hot or cold. At times there is a foul smell at the exhaust but not always. Unburned fuel? I will get the injectors cleaned but if it's the valves, what are my options"

Mar 20, 2008 at 1:45 AM

MASTERTECHTIM

✓Experienced Mechanic
4,750 POSTS

what code is stored in computer? you said he replaced a plug in one cylinder, why? did he do a compression check?

Mar 20, 2008 at 4:06 AM

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