Engine not getting enough vacuum after install

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Sep 24, 2005 | 01:30 PM

Cenco Fbody

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From: CA

Engine not getting enough vacuum after install

Hey guys, just had a 94 Opti and engine installed in a 95 a4 Z28. Now the Opti plugged in fine, but the motor wont pull more than 1" of cranking vacuum, whereas the toasted 95 engine pulled 5". Needless to say, the car is idling like s**t and isnt drivable. Anybody got any ideas?

Sep 25, 2005 | 01:03 AM

aintno6

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From: Romeoville, IL

So you did a motor swap. Or just swaped an opti over from an other motor?

Mike

Sep 25, 2005 | 01:11 AM

fcat8187

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From: plymouth,MN

leaky manifold, leaking vacuum lines try spraying starter fluid or carb cleaner anything really flammable around the manifold or were you think it is leaking and liten to hear if the motor RPM changes just be careful ***** super flammable

Sep 25, 2005 | 11:41 PM

Cenco Fbody

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From: CA

The motor was swapped, the engine is from a 94 and its got a reman'd Opti for a 94. I didnt do the swap, I had a shop do it. They are in over their head at this point, however, and havent got any answers. They did a smoke test and couldnt find any leaks. I'll check the lines when I get it home tomorrow, and maybe Ill try the carb cleaner. At least I have somewhere to start. Thanks guys.

Sep 26, 2005 | 02:13 PM

94strokedz

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From: Almont, MI

I'm not positive about this, but the 95 opti I think had a vacuum line going to it to vent it, and I'm positive the 94 does not. Possibly the line was never plugged, keeping it from building vacuum pressure. I know they switched from non vented to vented, I just am not sure when. My 94 is not vented.

Sep 26, 2005 | 02:22 PM

94strokedz

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From: Almont, MI

OK, I just looked it up. 95 was the first year of the vented opti. There is an in line and an out line going through the opti. The 94 does not have this. I bet the line for the opti which is not used on the 94 motor is not plugged. Did you do a complete swap, or just bottom end?

Sep 26, 2005 | 02:22 PM

Cenco Fbody

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From: CA

Yeah he mentioned something about that, but I thought he said that it was plugged. Perhaps he didnt, or plugged in something that shouldnt have been plugged in there.