Idle dropping and bouncing??

**suitercrew** · 01-05-2016

Not everytime but pretty frequently if i rev it when in park as soon as i let go of the accelerator rpms will drop really low and bounce back up. This has also happened at a light when i was stopped engine was idling fine right in the 700-750 range then when i went to give it gas rpms dropped really low then shot back up.

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**chris99gtp** · 01-05-2016

Check for vacuum leaks, clean the tb, and check the maf sensor. Any codes?

**suitercrew** · 01-05-2016

No codes i just got some carb cleaner to clean the tb and maf

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**FordMan77** · 01-05-2016

Don't use the carb cleaner on the MAF. Use MAF cleaner on it. The TB is ok. If you have some electronics parts cleaner around you could use that on the MAF.

**suitercrew** · 01-05-2016

Ok thanks. So ten minutes in im disconnecting the throttle body and theres two hoses that conjoin into one at the throttle body and where it conjoins there is a huge slice down the middle the two other hoses lead to the evap purfe solenoid and the fuel pressure regulator. Could this be a cause?

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**suitercrew** · 01-05-2016

Is there supposed to be puddles of oil in the valleys of the intake manifold and is the upper manifold supposed to have oil spray all over it?

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**SubwayGuy** · 01-05-2016

Originally Posted by suitercrew

Is there supposed to be puddles of oil in the valleys of the intake manifold and is the upper manifold supposed to have oil spray all over it?

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Yes, the PCV valve does that. Mine had it when I did the LIM. Not sure about the UIM though.

**suitercrew** · 01-05-2016

Why would they make it like that? What if you never changed it?

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**SubwayGuy** · 01-05-2016

Originally Posted by suitercrew

Why would they make it like that? What if you never changed it?

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Because GM. And change what, the PCV? Take it out and shake it. If you hear it rattle, then it's good and you don't need to replace it.

**Scottydoggs** · 01-05-2016

Originally Posted by suitercrew

Ok thanks. So ten minutes in im disconnecting the throttle body and theres two hoses that conjoin into one at the throttle body and where it conjoins there is a huge slice down the middle the two other hoses lead to the evap purfe solenoid and the fuel pressure regulator. Could this be a cause?

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that split is your problem. you need to hit a parts store, advance sells the best little t's. you need a Y and some vac line that fits the tb, then some smaller line to push inside the fat line, the Y to the other two small lines and the new line off the tb.

you'll need to cut or pull off th eold factory rubber end off the hard lines, then put a inch or so of new vac line on the end of the hard lines to the Y.

**suitercrew** · 01-05-2016

Well the one hose that goes to the purge solenoid has that fuel line connector on it so i thought it might be a "special order" kind of part unless that tip just pops off the hose?

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**Scottydoggs** · 01-05-2016

i just told you how to make a replacement. for less then 5 bucks too mind you.

**suitercrew** · 01-05-2016

O ok i see what your saying now. Ok thanks scotty sorry for the confusion

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**suitercrew** · 01-06-2016

Hey so im doing the rear vc gasket since its alot easier access with everything off but whats up with the gaskets on the bolts themselves because there breaking when i take them off and my new vc gaskets didnt come with any

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**Scottydoggs** · 01-06-2016

the rubber ring around the bolt is called a grommet. ask for them at the parts store.

**suitercrew** · 01-06-2016

Ok thanks scotty, have to make a trip to the parts store anyway cause they sold me the wrong lim gasket ugh.

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**Scottydoggs** · 01-06-2016

make sure its a metal lim gasket.

**SubwayGuy** · 01-06-2016

I got a factory replacement Y-hose from the junkyard for like $3 if you choose that route.

**HighOctaneRacing** · 01-06-2016

No it's not "cause GM". Many manufacturers use PCV valves. It's your responsibility to maintain your car properly. Just take it out and check it once a year.

Also I've used 4 different brands of PCV valves and the only one that has worked flawlessly is AC Delco.

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