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Discussion Starter · #1 ·
I have a 3800 series 1 in a 95 Regal Custom and believe I have a massive vacuum leak. Was looking for a vacuum diagram or possibly a pdf of the factory service manual if anyone has that and would like to share. I've found a few vacuum line diagrams in searches but none are specifically labeled for my model year so i'm not sure what I can/can't use.

My 3800 cranks and runs (although a bit rough) and it will immediately cut off if I don't give any gas. Have to work the gas pedal to coax it to start. Doesn't idle at all.

Car received a lot of new parts and ran perfectly fine before this work (but leaked a lot of oil), so I suspect I failed to hook something back up correctly. The lack of idle makes me think that its a vacuum issue. But since it WILL start I know I didn't break it too badly 馃槅
 

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Someone on here may have a diagram.
Unless a hose or connector is completely unplugged, I would think it would sort of run for ya. Try pulling out the idle air control valve and seeing how dirty it is. I have had them get stuck before. You can also try using a smoke machine. Im not sure what you exactly had pulled apart.

Best of luck!
 

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Discussion Starter · #3 ·
Someone on here may have a diagram.
Unless a hose or connector is completely unplugged, I would think it would sort of run for ya. Try pulling out the idle air control valve and seeing how dirty it is. I have had them get stuck before. You can also try using a smoke machine. Im not sure what you exactly had pulled apart.

Best of luck!
thanks for the reply. I found the correct vacuum diagram and verified the vacuum lines are connected correctly and damage free. I'll pull the IAC motor and have a look at it. Don't have a smoke machine unfortunately. The IAC motor actually makes sense. My jeep had a very similar issue years ago, but with the jeep once the engine warmed up the IAC could hold idle. That wasn't how it happened last time I tried to get this regal running.

I did find a loose connector near the firewall but don't know where it goes. It can almost reach the power steering pump. 2 pin connector colored red. Not sure exactly what it is. A couple diagrams i've seen say that its a VSS but I don't remember unhooking this, so maybe it's not VSS and actually unused on my model?

Regarding what I had apart, I had the upper/lower intake manifolds and valve covers out. A good majority of the engine harness was disconnected during that. But I also put new injectors in when reassembling everything with new gaskets. One of the old injectors cracked the pintle cap from plastic fatigue so I figured a refurbished set made sense. Hopefully that isn't what caused this to start happening. Really should have put those injectors in after everything else, as a way to minimize the variables changed.
 
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