Ok Long story short. driving down the road and I get a low coolant light on the dash. I pull over and top her up at gas station, then I turn it over and it starts running really rough and burns TONNES of coolant. I turn it off and try again but it'* hydrolocked.. so the first thing I do is hop on bonneville club and start reading. I found out the problem with the intake manifold and all of the symptoms apply so I start working. I changed both the lower and upper intake manifold gaskets after draining the coolant and oil. after I get her all back together I have the moment of truth and I turn it over. same thing happens again. runs insanely rough and then stalls. now its hydrolocked again. I pull out plugs and turn it over. water sprays out of #4 like niagra falls and maybe on the other side aswell. I am lost here and ANY help at all would be greatly appreciated. thanks in advance!

did you replace the UIM or just change the gaskets?

If you didn;t replace the UIM I would suspect that the actual manifold has failed. Which would be why it hydrolocked again

Did you empty the coolant out of the cylinders from the first time?

I did use the old UIM due to me being a lowly aprentice with no money. I was afraid that this could be the problem. I assumed that the problem was the gaskets because around the stovepipe the gasket was degraded from heat. I now am beginning to see things your way and realize it may cost me a few more bucks than i originally expected. so my questions to you are: Is there any way to check to see if in fact it is the UIM that has failed,and do i have to take EVERYTHING apart again or can i get away with just pulling off the fuel rail and UIM? I am assuming the my LIM gaskets are still ok because they are still brand new. oh and thanks for the speedy response. I am trying to get this done because i can't get to work with no car :(



and yes I pulled out all of the plugs and disconnected the coil and turned it over a few times to evacuate the cylinders. the first time it was dex cool coming out but this time i just used straight water and it was clean when it came back out.

Please put your year and model in your signature. Change out the UIM for a new one. You can re-use all the gaskets with no trouble. Also change the oil and filter at least twice to flush coolant out of the oil system.

Before you buy a new UIM, please read all of this article: http://www.bonnevilleclub.com/forum/...e=article&k=38

Since you did not replace the UIM I would put money on it that, that is what failed. You should only have to remove the fuel rail and UIM. Since you would only be replacing the black UIM.

Search around the forum, there are many threads about your different choices for manifolds. Depending on your year, 100ish should get you a new manifold.

In the mean time I would change your oil again.

thanks alot fellas! i really appreciate all of your info and suggestions. I am going to try and find a new UIM tomorrow and will deffinately be letting you all know how it goes for me. feel free to keep giving suggestions tho. i do appreciate everyone'* input and I am sure that many of you have been in the same boat. cheers!

If you can wait a day or two, you would be way better off to buy an APN UIM kit. Much cheaper and better than the Dorman.

well i couldn't wait so i had to get a factory plenum for 250 CDN at the dealer. I took it all apart and installed the new UIM, put it all back together, and now she turns over but no start. I am pulling my hair out here. I checked everything i took off and it all looks ok. there is spark and there is fuel in the rail. I checked the plugs and they are dirty so i cleaned them, then tried again, same thing, it wants to start but something is stopping it. I am so close to calling a mechanic even tho i can't afford to. welcome to my nightmare.