2000 Intake manifold gasket replacement

[kemp215]

Anyone give me any good tips on replacing my intake manifold gasket. I have a vacume leak in that gasket and it has caused my CEL with a misfire code.
Also...in the last couple of weeks my city gas mileage has decreased huge. On the hiway i get 800 km per tank..in the city its only 400km.
any tips on that?

[Eye8Pussies]

I presume you have a 4banger then considering the gas mileage that you're getting?

just take it apart and replace the gasket. the v6 gasket is a lot more work to do.

[kemp215]

ya its a 4cyl

[kemp215]

any ideas on whats causing the horrible gas mileage?

[Eye8Pussies]

no idea....it could be a whole lot of things

but if you're still getting 800km per tank on the highway, then I don't really see the problem...sounds like you're spending a lot of time idling and eating gas that way then

[Stillrunning]

Don't know how many miles on the car or when it was last serviced but if you're taking the intake off consider removing the injectors while your in there and getting them tested and cleaned. There should be companies in Canada that you can mail them to for this service. They'll do flow testing before and after, clean, and replace any parts you may need.

[Qslim]

Originally Posted by kemp215

any ideas on whats causing the horrible gas mileage?

Well, if you have a vacuum leak bad enough to cause a misfire, then the computer will have the fuel trim pegged as high up as it will go to try and compensate for all the extra air. A lean-running engine is not a good thing. You should replace the intake manifold gasket (if you are sure that is where the problem is) as soon as possible.

[kemp215]

Originally Posted by Qslim

Well, if you have a vacuum leak bad enough to cause a misfire, then the computer will have the fuel trim pegged as high up as it will go to try and compensate for all the extra air. A lean-running engine is not a good thing. You should replace the intake manifold gasket (if you are sure that is where the problem is) as soon as possible.

Thanks for the heads up...I plan on replacing in withing a week or so....although i have been running it for a few months with it like this. It took a while for the smoke test to show the leak.
Why is a lean running engine not a good thing?
also, thanks for the help guys...this site is great.

[Qslim]

Originally Posted by kemp215

Thanks for the heads up...I plan on replacing in withing a week or so....although i have been running it for a few months with it like this. It took a while for the smoke test to show the leak.
Why is a lean running engine not a good thing?
also, thanks for the help guys...this site is great.

Well, fuel mileage for one, as you've already experienced. Another concern from a lean-running engine is the heat associated with burning all that extra air. A super-lean engine can burn valves, spark plugs, and overheat the cooling system in general.

[kemp215]

Thanks Qslim.