99 Dodge Ram 2500 Evap Core replacement
dksob81
06-10-2007, 08:37 PM
here is my experience with replacing the evap core on my boss' 99 Dodge Ram 2500 5.9L. I replaced my evaporator core on my old 94 jeep grand cherokee and it is pretty much the same routine. So I talked my boss' into doing the repair, he didn't want to even fix it because he heard of what needs to be done. Well i did this yesterday at work took me about 4 1/2 hours. it's not that bad of a job at all, I did this by myself with little help here and there when needed. If I had to do it again i would and could prolly cut the time down to about 2 hours, now that I know where everything is at. Here are some instructions for all of you guys out there that have this problem and are a little elary about doing it.
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Evap core replacement 99 Dodge Ram 2500 5.9L
1. Disconnect battery.
2. Recover all remaining freon in the a/c system and drain engine coolant.
3. Disconnect a/c lines (3/4" and 7/8") Using disconnect tools and disconnect heater core hoses.
3, Disconnect vacuum line, going into the firewall by the a/c lines, at the "T", you may want to unbolt the drier and move it aside.
4. Remove the PCM (3) 8mm bolts (1 has a ground connected to it).
5. Remove the (4) 11mm nuts holding the HVAC housing to the firewall (1 is located behind the PCM).
6. On the inside of the truck, remove both driverside and passengerside kick panels along with the plastic cover in the center and the knee bulker (cover under steering column). Remove the Glove Box from the dash.
7. Remove the (5) Screw on top of the dash, next to the glass.
8. Loosen/Remove the (2) 13mm bolts, one on each side, in the kick panel.
9. Remove the (2) 10mm bolts holding the steering column to the dash. and remove the lower bar (5 or 6 philips/8mm screws, plus there is 1 more philips for the HOOD release) going across the lower dash under the column.
10. Remember to disconnect the AIRBAG connector, the BRIGHT YELLOW connector on the crossbar mentioned above.
11. Disconnect the Parking Brake release linkage.
12. Now you should be able to move the dash out far enough to see a few other connectors you will need to remove.
***You should be able to disconnect the big wire harness on the driverside (10mm center bolt) and all (3?) connectors surrounding this connector. then looking toward the center of the dash from underneath, you will see a connector going to the HVAC housing, disconnect it along with the 2 connectors on the front side of the HVAC housing on the passengerside.****
13. Remove the 10mm nut on the top of the HVAC housing (sticking out of the firewall, there is a ground wire connected to it) and another 10mm nut behind the ground wirie.
14. Underneith the passengerside dash looking straight up on the very end toward the kick panel you will see another (10mm) nut that needs to be removed, you may need to move the insulation out of the way to see it.
15. With help of a friend you will need to pull the dash out as far as you can, and then have them hold the dash up on the passengerside while you pull the HVAC housing off the firewall and out of the truck.
16. Now you will need to remove the EVAP Core from the HVAC housing, pretty self-explanatory.
17. Installation is reverse of removal.
** Don't forget to connect the ground wire to the top stud of the HVAC housing and the ground wire on the one PCM screw.
Also, the only real problems I had were the 4 nuts I had to remove in the engine compartment for the HVAC housing, they were really rusty and I had to use alot of PB Blaster and wire brushing, I finally got out the die grinder and put the wire wheel attachment on to clean up the studs and the nuts came right off. Then the 3 nuts (1 holds a ground wire on) on the inside, I didn't see them and there were no bolts/nuts holding the HVAC housing to the firewall on the inside when I did my jeep all the nuts were in the engine compartment, so I wasn't expecting them, I prolly wasted close to an hour trying to get the housing out, before I seen these nuts. and close to an hour on the other nuts trying to get them to come off.....lol
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I hope this helps someone else who needs these instructions. if anyone has any other questions about this just email me.......
Joe
[email protected]
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Evap core replacement 99 Dodge Ram 2500 5.9L
1. Disconnect battery.
2. Recover all remaining freon in the a/c system and drain engine coolant.
3. Disconnect a/c lines (3/4" and 7/8") Using disconnect tools and disconnect heater core hoses.
3, Disconnect vacuum line, going into the firewall by the a/c lines, at the "T", you may want to unbolt the drier and move it aside.
4. Remove the PCM (3) 8mm bolts (1 has a ground connected to it).
5. Remove the (4) 11mm nuts holding the HVAC housing to the firewall (1 is located behind the PCM).
6. On the inside of the truck, remove both driverside and passengerside kick panels along with the plastic cover in the center and the knee bulker (cover under steering column). Remove the Glove Box from the dash.
7. Remove the (5) Screw on top of the dash, next to the glass.
8. Loosen/Remove the (2) 13mm bolts, one on each side, in the kick panel.
9. Remove the (2) 10mm bolts holding the steering column to the dash. and remove the lower bar (5 or 6 philips/8mm screws, plus there is 1 more philips for the HOOD release) going across the lower dash under the column.
10. Remember to disconnect the AIRBAG connector, the BRIGHT YELLOW connector on the crossbar mentioned above.
11. Disconnect the Parking Brake release linkage.
12. Now you should be able to move the dash out far enough to see a few other connectors you will need to remove.
***You should be able to disconnect the big wire harness on the driverside (10mm center bolt) and all (3?) connectors surrounding this connector. then looking toward the center of the dash from underneath, you will see a connector going to the HVAC housing, disconnect it along with the 2 connectors on the front side of the HVAC housing on the passengerside.****
13. Remove the 10mm nut on the top of the HVAC housing (sticking out of the firewall, there is a ground wire connected to it) and another 10mm nut behind the ground wirie.
14. Underneith the passengerside dash looking straight up on the very end toward the kick panel you will see another (10mm) nut that needs to be removed, you may need to move the insulation out of the way to see it.
15. With help of a friend you will need to pull the dash out as far as you can, and then have them hold the dash up on the passengerside while you pull the HVAC housing off the firewall and out of the truck.
16. Now you will need to remove the EVAP Core from the HVAC housing, pretty self-explanatory.
17. Installation is reverse of removal.
** Don't forget to connect the ground wire to the top stud of the HVAC housing and the ground wire on the one PCM screw.
Also, the only real problems I had were the 4 nuts I had to remove in the engine compartment for the HVAC housing, they were really rusty and I had to use alot of PB Blaster and wire brushing, I finally got out the die grinder and put the wire wheel attachment on to clean up the studs and the nuts came right off. Then the 3 nuts (1 holds a ground wire on) on the inside, I didn't see them and there were no bolts/nuts holding the HVAC housing to the firewall on the inside when I did my jeep all the nuts were in the engine compartment, so I wasn't expecting them, I prolly wasted close to an hour trying to get the housing out, before I seen these nuts. and close to an hour on the other nuts trying to get them to come off.....lol
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I hope this helps someone else who needs these instructions. if anyone has any other questions about this just email me.......
Joe
[email protected]
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