Vacuum lines?

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SHO9391

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My 91' isn't running too good. As a matter of fact it's not running at all, now. It started when I changed my valve cover gaskets. Before I started, I noticed gas was squirting out of the fuel dampener. I got the gaskets changed and the intake manifold put on, and I got a new fuel pulse dampener. Now, it ran for a while, not very good, but it ran. The engine was pretty shaky, and there was a strange whistling noise after I let off the gas. I didn't drive it, just reved it up to about 2,000-2'500 RPM's. And the air box was making a lot of noise, like it was letting in way too much air.
I pulled the codes an I got a 21, a 91, and a 25. I also got a 22 with the engine off test.
I'm wondering if I shouln't replace the fuel pressure regulator as well.
It was my first time taking off the Intake manifold, and Ive looked at everything, and it seems to be in order.
Sorry for the long post, and I hope you guys can help me.
 

sdpatt

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The whistle was probably a vacuum leak. The fuel pulse damper? That was probably the fuel pressure regulator on the passenger end of the fuel rails. If that was leaking fuel then you definitely need a new fuel pressure regulator. What all did you remove to get the valve covers off? There are detailed procedures available.
 

SHO9391

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The regulator is the one with the hose coming out of the top, right? I replaced the thing right below it. It did not have a hose, but it had a little rubber ******, and thats where the gas was coming out. It looked just like the regulator, except without a hose. As for the valve covers, I tried not to take off any thing I didn't need to. I did take the intake manifold apart though. I got it started and the whistling seems to be coming from the valves(?) in the middle of the intake on the inside edge. They open and close the ports(?). Not sure what they are called. One more thing. The front row of spark plug wires were in wrong (Chiltons). Got theminthe right way, and ran the codes. I got a 12 this time. All clear on the engine off test.
 

RogueSHO

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one thing you may want to investigate, the things that you don't know what they're called... sounds like the secondaries. they're these "butterflies" that give the engine that mean ass torque and growl above 4k (technically it's 3950rpm but the tach lags anyway and it will seem like 4k). these are meant for the high rpm's and therefore make idling poopy if not closed. so what you do here is, take a look at the big square intake... look in the middle inside edge of the front and back... you have the OOO bracket area that has an open hole with a lil' rod actuator and a small triangular piece poking out and under it will be the solonoid and vac line, a likely culprit (i believe looking at the engine, on the end closer to the windshield, it's about here O,OO). you can push (up?) on the tiangular piece there to close them (engine off=open). when you turn your key to the on position, they should flip. have someone turn the key for you and watch them. hope i've helped... and if you already knew this, sorry to babble.

btw, mine don't work right now. shrug
 
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