Ok fellas here is the scoop. I just finished putting my turbo in and what not. I still have not put the FCD on there as well as I am still runing regular unleaded fuel. When I started up the car just to see if everything was good and to see if it would turn over it idled for a min at normal then it would slump down into a very rough idle. I would say 800rmps. I tried to give it some gas and it would jump up and run just fine. But it would hesitate for second before raising the rpms. I took it up to 4-5 grand and it was fine and what not. Boost gauge didn't move all to much. So does anyone know the source of the problem. I think it is a vacuum line somewhere. I don't think the fuel or the hook up of the FCD should matter since I am just letting it go at idle. So any thoughts on what it could be? Thanks.... Oh and I know there are tons of items on rough idleing but I couldn't find one that was simular to my problem.

check for vac leaks . i almost possitive its that

Originally posted by boosted60trimrst
check for vac leaks . i almost possitive its that

Ditto.

This is how i found a tough one
i filled the engine with smoke from a cigarette
then watched for where it moving to
led me right to a leak

Ok i have been searching for two hours with two other people and we can't seem to find any open vacuum lines anywhere. I mean I have undone them all and held my finger over it and it still idles rough. What am I suppose to be idleing at? I would think that it would be the same as it was before but I am not sure. Also when I start the car the boost/vacuum gauge reads 15 in the vacuum region. Is that suppose to read like that?

Originally posted by xlr82x
Ok i have been searching for two hours with two other people and we can't seem to find any open vacuum lines anywhere. I mean I have undone them all and held my finger over it and it still idles rough. What am I suppose to be idleing at? I would think that it would be the same as it was before but I am not sure. Also when I start the car the boost/vacuum gauge reads 15 in the vacuum region. Is that suppose to read like that?

15 vac sounds about right. A vac leak doesnt necessarily have to be at a connection, it could be cut somewhere so follow the lines and look for cracks or cuts. does the vac gauge stay constant at 15 in/hg? Mine used to sit at 15 then slowly rise up then the car would die. /shrug

Originally posted by xlr82x
When I started up the car just to see if everything was good and to see if it would turn over it idled for a min at normal then it would slump down into a very rough idle. I would say 800rmps.

Do you mean 8k right below the 1 mark? If so mine idles a bit lumpy/ruff at 7k. Which I think between 7 and 8 is normal. If not, please disregard this message.

You don't mean 8k, you mean 8 hundred. 8k is 8 thousand. ;)

It's supposed to idle there, anywhere from 800-900 rpms.

If it's a rough idle, then that's something different. Have you disconnected your spark plug wires one at a time to check for a dead cylinder?


Brian

First off the guage stays constant at 15 vacuum until you give it a lot of gas this it rises up a bit but is still in the vacuum range. That could be because I have not installed my FCD yet and will be doing that tonight. Second, as far as the whole cyclinder thing, I don't believe i have a blown cyclinder since I check compression before I started this whole project. They were all in the green so I think I am good there. It is running around 8 hundred rpms, just thought it was feeling a bit rough because orginally it was a little higher and the car didn't shake at all. So if it is suppose to be around this area then i think I am good. I guess the only way i can offically tell is later on tonight when I install the FCD. So thanks for the help and if you can throw out any more suggests that would be great.

Ok, I'm glad you checked the compression beforehand. (what did you get by the way?)

Your FCD is not going to help the situation. Do you know what this thing does?

It's designed to prevent the MAP sensor from seeing positive pressure, something that doesn't happen with NA cars. you need this because if the MAP sees positive pressure the ECU freaks out and prevents you from going any further. Since you can't get boost in idle, your FCD will not help you.

The boost gauge is rising because you're opening the throttle plate and allowing more air to rush in, thus not as much vacuum is present in the manifold.

You have a rough idle, which could be caused by a number of different things. Spark plugs, wires, compression, fuel injectors, IAC, dirty intake manifold, bad sensors (MAP, MAT, TPS, CLT)....etc, all of which could be possible problems. Or you just could see about upping the idle a little bit, or checking your throttle cable. Both of them could be an easy culprit.


Brian

EDIT: I forgot to ask, what fuel managment are you running? That could be the culprit too.

compression was 180+ in all four cyclinders meaning I still have a little time before the whole car dies. As far as the FMU, I am just running and regular OBX 12:1 FMU ( I know not the smart thing but it was free and will be upgrading here shortly with the sfmu.) I had an idea on what the FCD did and knew that its only application was when the car was driving. But see i bought the car with one of those fagot ass spacers in there and have been wanting to take it out because yea they do nothing. I just ordered the bolt two days ago and will be picking those up a little later. Not sure if that will help any but I think it will make the car look a little better without that spacer. I just got done starting it up and again and I let it run a bit just to see what would happen. It stooped down to 6 hundred then came back to 1k and then to 8 hundred and held there until i turned the car off. I don't think it is fixed but that is just what happened. i would have given it a bit of gas but yea we all know what would have happened there without the FCD.

Originally posted by xlr82x
i would have given it a bit of gas but yea we all know what would have happened there without the FCD.

Yup. Nothing would have happened.

As has already been tried to be explained to you, the FCD provides protection from POSITIVE boost pressure reaching the map sensor. you will never see positive boost pressure until you spool up the turbo and get past 0 vac. Even if you revved the shit outta your car in neutral you might *MIGHT see 1psi if even that...

At this point it sounds like you need to spend some of this downtime on research and the basics of turbocharging a car and how all these pieces that you bolted work together. Without that basic knowledge you are bound to have countless problems and no basis for where to start to look to even fix them.

g/l

First off. I have done as much research on this as possible at this time. This is a new area for me and I know that when others did this theya also had problems with their shit. so don't think that I didn't do research. Secondly, I started the car and gave it gas. The car hesistated and then when up. I tried to do WOT on it and it couldn't even raise the RPMs. Is this a vacuum problem. I noticed a post said that there is a lot of shit that could go wrong so I am just looking for advice on where I should be starting my search. Because if i understand what you are all saying, the car should rev up with no problem unless I am not getting something. and I was running the car and the check engine light came on so I took it to auto zone and let them do a read out and it turns out the my o2 sensor in bank 1 (down pipe) is working correctly. I am not sure if i should be replacing this because the sensor was fine before i started the project. And the guy who i got the header from painted the inside and out side of the header and I am thinking that that had something to do with it but I am not sure. Any thoughts?

Do you know what the idle fuel pressure is? When you say "rough" idle, does it rise and fall (sporatic) or does it stay at a certain rpm for a while before changing? If you've ruled out a vac leak in your lines & at the throttle body, then I'd double check the ignition stuff like ForceFed420a mentioned in his post.

ya id check the ignition cause it sound like ur rich as hell if u floor it and the rpms wont rise g/l man