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Help!!
I just replaced my DOHC engine and when I stareted it up, it idled at 4800 rpm. I've checked all my connections and can find nothing out of place. The engine ran just fine before removal to put into mine. I kept all the wiring intact during the switch. It drives down the road normally and gives no engine trouble codes after 30 miles driving. Still idles at 4800 rpm. I pulled the PCV hose off and started it. It struggled for a moment and then went to its 4800 rpm idle. If I remove the MAF connection, it will idle very roughly at low rpm but as soon as it plug it back in, back to the 4800 rpm.

Help!! Any ideas?
 

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Check your TPS sensor. It is hooked up to the Throttle Body, than I would check the PCV Hose. It is the hose that connects from your Valve cover to your air box.

be sure to check all relays and fuses as well.
 

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How would timing out 180 cause high idle ?

I would check for a Vac leak and check that your throttle plate is closed all the way , when you confirm no vac leak with engine running unhook th idle air controle valve the engine should die , restart and set TB idle screw to 750 then plug idle air controle valve back in

Tom
 

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Check your TPS sensor. It is hooked up to the Throttle Body, than I would check the PCV Hose. It is the hose that connects from your Valve cover to your air box.

be sure to check all relays and fuses as well.
The PCV hose connects from the PCV (center of block behind header) to the back of the intake manifold

Tom
 

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Hatch Nation #136
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Everyone that I have heard that has set their timing out by 180 said that their RPMs raced.
 
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