my 4.0 aerostar has exsessive n. o. reading.i changed the mas sensor and the check engine lite is now out.what other repairs should i do before i retest it?
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1995 Ford Aerostar Question: failed smog test
Answer #1mastertech6371 September 07, 2010, 16:49Master
the mass air flow controls hc and co. nox is controlled by egr and cat converter. you had more than one problem. have these 2 items checked for operation
Replyshadetreeauto, September 08, 2010, 10:42Master
thanks for your reply.i was hoping not to replace the cats as they are high dollar.ill change the egr and see what i get.if it still wont pass ill have to take it to the referee.