have a 99-00 y8 IM(has colds start assist)on a z6 head was on car when i bought it. its causin my car to have a vaccum leak between the IM and the head on the same side as the distributor. its causin my car to idle high. when i drive the car for a while and i push on throttle at like 2k rpm it does like a boggin noise. so i have to push on gas harder it doesnt do it. but it makes it hard to drive cause car bucks when takin off unless i give it more gas. did the person before me do something wrong to IM swap and also which IM gasket do i need y8 or z6 any info would help alot this is annoyin ty

 

I did this exact swap and the IM should be a direct fit to the head no problems. Mabye they didn't scrape all of the old gasket off before putting the new one on but either gasket will work, I used the y8 IM gasket on my swap... Post back and let us know if we can help with anything else

 

so i need to scrap it off the head also correct cause a friend took it off the IM but he didnt check the head and ty atleast u gave me hope