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To replace the intake manifold on your vehicle the book time is 4.5 hours. You will also need to purchase some intake manifold gaskets, coolant, and possibly an EGR gasket if the gasket becomes damaged upon removal. If some coolant goes down into the engine during removal you will also need to do an oil change when the job is completed. Looking at the OEM price for the intake it is $358.32 the price may be different depending on the location where you purchase the part. You will need to purchase around 2 gallons of coolant, if it is not mixed you will have plenty if you buy pre-mixed you may need to purchase another gallon to be safe with having enough. The price of the parts / supplies will vary depending on your location and where you decide to buy the parts (depending on if you try to purchase from the dealer or after market parts stores). The dealership may not be able to get the parts as a lot of times after ten years they stop stocking and making the parts. If you have any questions please let me know and I will gladly assist you with you question. Thanks once again for choosing Just Answer!
The cost for labor will be 4.5 hours (if they charge $65 an hour = Roughly $300).
Intake manifold would expect around $350 or less.
Gaskets should be under $50 for everything needed.
Coolant 10 - 15 a gallon (non mixed should be $30 or less for all of the coolant you will need).
The complete job could be no more than $700 to replace the intake manifold.
Do you happen to have a write up of the quote?
The book time is 4.5 hours (which even at $100 would be $450)
$450 plus gaskets ($50) and coolant (on the high side no more than $30) = $530.
The rest of the cost would depend on the cost of the intake which looking at the OEM estimated cost it was $359, this price may be off if they have not updated the cost in some time and due to the availability of it may be more or less depending on location.
Here is a link on the intake to get an idea of what the problem is and how to make sure the issue is properly addressed. http://www.autoclinix.com/Manifold.htm
I did a quick search on line and the intake is $343, which includes a new thermostat and gaskets. http://www.partstrain.com/store/index.php?VN=4294967193+4294966864+4294965966+4294967022+4294966883&Nr=AND(universal:0)&N=0&Ntt=Intake%20Manifold
The price seems a little high. You may want to call around to other shops to get a quote over the phone, unless the shop is recommending other things in that quote then it seems to be fairly overpriced.