FORD 302 vacuum lines causing car to run crazy and backfire?

I have an 89 crown Victoria I been building its almost done but my vacuum lines are causing the car to dump gas idle high and want to cut off when the hoses that suck are connected or blocked i'm trying to figure out where do they go I took the engine and tranny out of an 89 or 90 Lincoln town car they are dropped in the car it crunk right up ran with no problem but when we tried to drive i it was hesitating to speed up as I could hear the air leaks but now maybe a week later after covering it up and leaving it alone when we tried to hook up the vaccum lines that run from the front of the intake and the back it started to backfire and want to cut off my friend suggested we scrap the fuel injection and convert it to a carb can anyone help on this

I would just replace the lines. Look for cracks in them first off. Also check where they connect. If they slide on and off easy replace them or hose clamp em. If its not the lines could it be that the distributor is out of time? That will cause it to miss. I doubt a 02 sensor would cause it because back then the computers in those cars were too weak to really pick up a good reading on them. Maybe the EGR is plugged? Or the idle sensor might be bad? Could be a lot of things.

Get a vacumn chart. Its likely under the hood around the radiator plastic or up on the under side of the hood or just look on internet for vacumn chart for 89 ford 302 engine (maybe under inages) or find another car and look at it for camparision. If there's a vacumn leak it will run fast because the idle valve will open to keep it running because it would stall with the leak

First, don't try to switch it to carbureted, that would be a mistake.

Next, go back to basics. Connect the Brake Booster hose and PCV hose then plug off every manifold port you can find. Then see how it runs and sounds. If it still runs bad and you still hear the hissing of a vacuum leak, find and fix that leak. Once you have cured all hissers see if it runs good, if good proceed to next steps.

The VECI (vehicle emission control information) label has the vacuum diagram. It should be either on your radiator cowl or the fender well. Follow that diagram and you should be able to sort out all of the vacuum lines.

They hook the same places your old ones did

Try to do a search on Google, maybe that will work out

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