I am running a Honda D15B7 in a sandrail and seem to have a problem with vacuum lines. Since I am not running anything accessories wise I do not need the vacuum's yet if I plug them the car will not idle? If I unplug the one that runs to the brake booster the car idles high (which it should) I just don't know where to go with this or if my timing is off and that is why it will not idle when I plug all the vacuum's. I did change the timing belt and could have gotten it off a tooth or so? Any help would be greatly appreciated.

 

Some of the vacuum lines contribute to air intake, so if the hoses are plugged the idle will reduced.

I don't understand why you want to plug all the vacuum lines. Please explain. Is the idle problem specific to a cold or warm engine or both?

You can check the ignition timing with a timing gun but, if the engine runs fine at low and high rpm under load, then the timing is probably fine.

 

The reason I plugged them was because I am running no Brake Booster and don't have the diagram of where all the other vacuum lines go. When first starting it up it runs fine for a few seconds and then it starts to run rough once it starts to warm up. At about half throttle it runs like its missing, but I am guessing that is related to the vacuum. I have tried running all the vacuum lines together and it still does not work. The main question is where do I run them to in order to solve this problem of the lines having to be plugged? Thanks for you help!

 

The plugged vacuum lines will affect the idle, but not how the engine runs above idle speeds. As you mentioned, check the mechanical and ignition timing.

 

Another thing has come up in this whole things. I currently don't have MAP sensor could this cause the engine to run like crap? I know the TPS should read .49 volts at closed throttle and 5.0 at wide open! I don't know if this has anything to do with it but the TPS right now reads 5.0 volts at all times, even when changing the throttles position. When I removed the ref. Voltage wire it is 5.0 volts at closed throttle and 14.3 at wide open? I am guessing this could be part of the problem beings that the ECU thinks it is wide open at all times therefore giving it more fuel than it actually needs?!?! I am just going out on a limb here... If I confused you with all of this please let me know
Thanks again

 

Yes, proper functioning of the MAP sensor and TPS is absolutely critical. Do you have a way to retrieve CEL codes from the ECU (see link in my signature)?

 

From what I get is that all you need to do it hook up a light to the CEL wire off the ECU and it will flash so many times when you turn the key on? so not having the MAP could cause the TPS to not function properly? when you disconnect the plug off the TPS nothing changes in the motor...

 

Retrieving CEL codes is detailed at the link in my signature. For the engine to run properly, you must have a functional MAP sensor and TPS.