01 lanos heater core replacement

[lanos01hatch]

Help please just got done putting pretty much new top end on my lanos now lost heat except when rpms are high temp gauge is running normal was told its heater core. Anybody have any tips on doing this job pics or step by step would be helpful

[Daniel]

Hum. Seems to be a big job...removing dashboard...recover airco refrigerant...removing heater box...removing heater core...
All the procedure is in the service manual. To get one look in the FAQ section "where to download service manual"...

Are you sure it's heater core? Maybe clogged. Try to backflush it from firewall hoses.