Vacuum Hoses
Dude050
09-01-2005, 11:00 PM
Im new the the board and want to say wassup to all out there.
About a month ago i boutght an 87 crx SI from this guy. He said the car had been sittin for about 2 years. Well i did a tune up that included plugs, oil change, hoses, brake pads, battery, and a new radiator. I got the car to start after crankin it a couple of times but it would rev all the way up to 7,000 (not kiddin). Even after lowering the idle screw and adjusting the throttle cable it still reved to about 6,000. After about 3 hours i got frustrated with trying (about 2 am) an went to bed. I looked online at a couple out pictures of engines, but none of them were too clear to see everything. Thats when i noticed the colored vacuum tubes on the intakes of all the pics. I went back to the car and it had one uncolored and two yellow lines (instead of the blue, yellow, and i think red). I then rewired them as best as i could (based on the pics on the web) and got it to idle down to about 900. After idling for about 5 mins the PGM-FI light came on, and the car reved to about 1,500. I checked the ecu next and got ( 0x0x ) to light up on it. In the Haynes book, it says that it could be either the MAP sensor, the Ecu itself, or i think the oxygen sensor. I found that the Map sensor hose was unplugged so i plugged it in, reset the ecu (unplugged the battery and the hazard fuse, correct?) then started the car back up. The car idled back at 900 then reved up and bounced from 3,000 to 4,000. Does anyone have a diagram or any clear pics of how the vacuum lines are supposed to be plugged in? Will i need a new Map sensor or maybe a TPS?(read that i have to buy a whole new throttle body or use a dremel to turn it into a screw, but id rather buy a new throttle body instead of going through the trouble)
Another problem, the gas line has rusted out and a piece to the return line. (underneath the side skirt, towards the front of the driver side rear tire, and under the gas tank pipe) Does anyone know what this piece is and how much itll be to get fixed or if i can fix it myself? I want to make sure that the high pressure hoses that i put in its place wont leak and plus winter will be rollin through pretty soon here in Ohio.
Thanks
About a month ago i boutght an 87 crx SI from this guy. He said the car had been sittin for about 2 years. Well i did a tune up that included plugs, oil change, hoses, brake pads, battery, and a new radiator. I got the car to start after crankin it a couple of times but it would rev all the way up to 7,000 (not kiddin). Even after lowering the idle screw and adjusting the throttle cable it still reved to about 6,000. After about 3 hours i got frustrated with trying (about 2 am) an went to bed. I looked online at a couple out pictures of engines, but none of them were too clear to see everything. Thats when i noticed the colored vacuum tubes on the intakes of all the pics. I went back to the car and it had one uncolored and two yellow lines (instead of the blue, yellow, and i think red). I then rewired them as best as i could (based on the pics on the web) and got it to idle down to about 900. After idling for about 5 mins the PGM-FI light came on, and the car reved to about 1,500. I checked the ecu next and got ( 0x0x ) to light up on it. In the Haynes book, it says that it could be either the MAP sensor, the Ecu itself, or i think the oxygen sensor. I found that the Map sensor hose was unplugged so i plugged it in, reset the ecu (unplugged the battery and the hazard fuse, correct?) then started the car back up. The car idled back at 900 then reved up and bounced from 3,000 to 4,000. Does anyone have a diagram or any clear pics of how the vacuum lines are supposed to be plugged in? Will i need a new Map sensor or maybe a TPS?(read that i have to buy a whole new throttle body or use a dremel to turn it into a screw, but id rather buy a new throttle body instead of going through the trouble)
Another problem, the gas line has rusted out and a piece to the return line. (underneath the side skirt, towards the front of the driver side rear tire, and under the gas tank pipe) Does anyone know what this piece is and how much itll be to get fixed or if i can fix it myself? I want to make sure that the high pressure hoses that i put in its place wont leak and plus winter will be rollin through pretty soon here in Ohio.
Thanks
lxndr
09-02-2005, 11:24 PM
My guess would be the O2 sensor or a vacuum leak. You might be able to find the vacuum diagram at www.redpepperracing.com.
The return line is not under high pressure, you can fix it by cutting out the damaged area and splicing in a rubber fuel line. For the supply line you could cut out the damaged area, flare the ends, then splice in a piece of steel tubing. A rubber hose will probably work for the supply side too, but I don't want to suggest something that may not work.
Welcome to the AF!
The return line is not under high pressure, you can fix it by cutting out the damaged area and splicing in a rubber fuel line. For the supply line you could cut out the damaged area, flare the ends, then splice in a piece of steel tubing. A rubber hose will probably work for the supply side too, but I don't want to suggest something that may not work.
Welcome to the AF!
otto203
09-04-2005, 12:30 PM
did you get your prob corrected? i had the same prob. what i did to correct the prob was to change the idle control valve, the cylindrical peice that is attached to the backside of the throttle body. on the top of it are two philips screws, start these turning first with a vise grip, then, open the lid. inside of the cylinder is a black plastic donut shaped disc, plug this hole with your finger or someting while the car is running. if the engine is idling better, change this peice.
avistar
09-04-2005, 01:01 PM
did you get your prob corrected? i had the same prob. what i did to correct the prob was to change the idle control valve, the cylindrical peice that is attached to the backside of the throttle body. on the top of it are two philips screws, start these turning first with a vise grip, then, open the lid. inside of the cylinder is a black plastic donut shaped disc, plug this hole with your finger or someting while the car is running. if the engine is idling better, change this peice.
First off take a can of carb cleaner and spray it on all the hoses and gaskets while it is running. If there is a dramatic change along the way you will have found your vaccuum leak. If not, try the following:
Just take out one screw and loosen the other. Slide the cover over to one side gently. There is an O-ring under there so don't lose it. You will see a large slot inside and it needs a verrry wide screwdriver or use a 1" chisel to tighten it up a bit. Be careful as it damages easily. This usually does the job but not always. You can also screw it out and clean it up a bit.
It is basically a temperature sensor of sorts and there is a water hose attached at the bottom of the unit that heats it up. Sometimes if your system is not bled properly there will be air up there and cause the surging. It's a tough problem to track down easilly. You could also try to disconnect the wiring from there while car is running and if it evens out that may be the problem. It will throw a code and you will need to reset the ECU.
If you can find one at the wreckers you could try and replace it. I believe the manual has a section to test if it is working correctly with an ohm meter. Hope that helps. JS
First off take a can of carb cleaner and spray it on all the hoses and gaskets while it is running. If there is a dramatic change along the way you will have found your vaccuum leak. If not, try the following:
Just take out one screw and loosen the other. Slide the cover over to one side gently. There is an O-ring under there so don't lose it. You will see a large slot inside and it needs a verrry wide screwdriver or use a 1" chisel to tighten it up a bit. Be careful as it damages easily. This usually does the job but not always. You can also screw it out and clean it up a bit.
It is basically a temperature sensor of sorts and there is a water hose attached at the bottom of the unit that heats it up. Sometimes if your system is not bled properly there will be air up there and cause the surging. It's a tough problem to track down easilly. You could also try to disconnect the wiring from there while car is running and if it evens out that may be the problem. It will throw a code and you will need to reset the ECU.
If you can find one at the wreckers you could try and replace it. I believe the manual has a section to test if it is working correctly with an ohm meter. Hope that helps. JS
Dude050
09-06-2005, 10:46 AM
I was actually able to fix it a few days ago. The previous owner had the hoses plugged in incorrectly, so i was able to find a diagram and rerouted the hoses. the car runs like a champ now. Thanks for the help you guys.
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