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Thermactor Troubleshooting Help

  • Thread starter Thread starter pstang89
  • Start date Start date Jun 3, 2012
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pstang89

New Member
Jun 22, 2011
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Jun 3, 2012
#1
  • Jun 3, 2012
  • #1
This forum has been such a great help, now here are my latest questions. I've been troubleshooting a code 94 driver side secondary air injection inoperative. Maybe the drivers side head is blocked, but I'm starting to think I just have a really low flow from the smog pump. Followed diagnostic info from jrichker.

1. Crossover tube is totally clear, but I did not shoot air into the heads so I don't know how good the passages are.

2. Chased out the air tubing from the smog pump. The air diverter valve operates properly. HOWEVER, the air bypass valve seemed to always blow through and not dump to atmosphere.

3. The air bypass valve rattled and had a bunch of carbon/plastic looking debris in it, but I could never get it to dump to atmosphere so I will get another. After destructively opening it up (why can't people make this junk rebuildable?) I am sure that debris was keeping the valve from seating.

4. QUESTION: if the dump valve was always blowing through and not operative, would code 94 possibly get thrown because little or no condition change occurred during testing?

5. QUESTION: The smog pump definitely blows out air, but it didn't seem like a lot or very much pressure. It pulsed a little, and it was easy to block the flow with my hand. Does the black plastic debris indicate that the pump is partially fragged? Can the pump be rebuilt or just buy another?

6. QUESTION: I hooked a hose to each of the check valves and blew into them. They both flow, but they seem to have more resistance than the smog pump could overcome. Any idea what is normal?

Thanks in advance for your help.
 

jcgafford

10 Year Member
Jan 7, 2012
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Jun 3, 2012
#2
  • Jun 3, 2012
  • #2
5. my smog pump hardly moves air either. might be normal, might not. never got a good answer on airflow from it. on another note i have both diverter and bypass if you need them, oem they work. but to test them all you need is to provide vacuum to them and they will open or close.
6. is this the "check valve" on the diverter? you should apply suction to it, not airflow.
 

jrichker

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The black junk is likely to be the vanes from the pump. Sooner or later, the pump will probably seize up stranding you somewhere you don't want to be....
 
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pstang89

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Jun 22, 2011
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Jun 3, 2012
#4
  • Jun 3, 2012
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Thanks for the quick answers. For item 6 I actually blew air in the check valves that lead to the crossover pipe and the lower exhaust. Unless the smog pump flows a lot more air volume and pressure at speed than at idle, I don't see how it could ever inject enough useful air. Going to find another air bypass valve locally. Still wondering if I should tear apart the smog pump or consider a rebuilt since I found debris downstream.
 

jrichker

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  • Jun 3, 2012
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pstang89 said:
Thanks for the quick answers. For item 6 I actually blew air in the check valves that lead to the crossover pipe and the lower exhaust. Unless the smog pump flows a lot more air volume and pressure at speed than at idle, I don't see how it could ever inject enough useful air. Going to find another air bypass valve locally. Still wondering if I should tear apart the smog pump or consider a rebuilt since I found debris downstream.
Click to expand...
"Tear apart "is the operative phrase in this dialog. I "tore one apart" quite literally. Once they break, most of us ordinary guys may find it very difficult to successfully disassemble it and reassemble it in a working manner...
 
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