Two Problems - IAC and Injector Leak Down
Thread Starter
Burning Brakes
Joined: Aug 2005
Posts: 772
Likes: 6
From: Huntsville AL
Two Problems - IAC and Injector Leak Down
1988 Conv. 153000 miles.
My idle is too high but all adjustments to idle set screw and TPS are correct. I removed the IAC and cleaned and it worked great for one trip but now idles too high again. I want to remove the TB and clean all passages and everything before I buy a new IAC.
Also - I have the typical delayed start when warm and you can smell fuel in the exhaust when it does start. I want to remove the injectors and clean good and check for leak after cleaning.
Questions.
1. How much coolant will I loose when I remove the coolant lines from the intake? Do I need to drain the radiator a bit?
2. What all has to come off to get the injectors out? Do you really have to remove the entire intake system? If so - what all gaskets am I going to need to replace?
I have all the tools and the ability and the shop. Just never done it before.
Thanks,
Tony
My idle is too high but all adjustments to idle set screw and TPS are correct. I removed the IAC and cleaned and it worked great for one trip but now idles too high again. I want to remove the TB and clean all passages and everything before I buy a new IAC.
Also - I have the typical delayed start when warm and you can smell fuel in the exhaust when it does start. I want to remove the injectors and clean good and check for leak after cleaning.
Questions.
1. How much coolant will I loose when I remove the coolant lines from the intake? Do I need to drain the radiator a bit?
2. What all has to come off to get the injectors out? Do you really have to remove the entire intake system? If so - what all gaskets am I going to need to replace?
I have all the tools and the ability and the shop. Just never done it before.
Thanks,
Tony
Former Vendor
Joined: Jun 2001
Posts: 7,204
Likes: 6
From: St Marys PA
drain the radiator, but before you do that I would try to locate, what I think is a vaccuum leak. The gaskets get old and you start sucking air in that is not suppose to be there and you will get a high idle from it.
Easy way to find the leak is with Ether (starter fluid). Let the car idle and go around the seams spraying a little at a time. When you hit the spot that is leaking the cars idle will pick up.
Use the stuff in very small amounts, its flamable.
yeah the upper part of the intake will need to come off to get at the injectors if you need to do that, but I would try the above first.
You might find its something pretty simple to fix.
Good luck!
Easy way to find the leak is with Ether (starter fluid). Let the car idle and go around the seams spraying a little at a time. When you hit the spot that is leaking the cars idle will pick up.
Use the stuff in very small amounts, its flamable.
yeah the upper part of the intake will need to come off to get at the injectors if you need to do that, but I would try the above first.
You might find its something pretty simple to fix.
Good luck!
Thread Starter
Burning Brakes
Joined: Aug 2005
Posts: 772
Likes: 6
From: Huntsville AL
Possibly found one problem
Found a vacuum line loose. Must have come off while changing the plug wires. Plugged it back up. Seems to idle better but at work so will have to see on the way home.
Still think I need to pull and clean the injectors for the leak down. Is there not any way to get them out without removing the pipes from the intake? I think at most I could do one side and then the other and that would keep me from disconnecting the coolant lines going to the TB.
Thanks,
Tony
Still think I need to pull and clean the injectors for the leak down. Is there not any way to get them out without removing the pipes from the intake? I think at most I could do one side and then the other and that would keep me from disconnecting the coolant lines going to the TB.
Thanks,
Tony
Drifting
Joined: Mar 2005
Posts: 1,923
Likes: 0
From: GA
Originally Posted by thomastl
I think at most I could do one side and then the other and that would keep me from disconnecting the coolant lines going to the TB.
Thanks,
Tony
Thanks,
Tony
You don't have to disconnect the coolant hoses from the throttle body. Just remove the throttle body from the plenum and let it sit there. Also, you don't have to remove the runners from the intake to get the rails up, though it will make it a bit easier. You do, however, have to remove the plenum and while you have it off, check your EGR valve, it is the perfect time to make sure it opens and will stay open.
Race Director
Joined: Jun 2004
Posts: 13,961
Likes: 707
From: WI
Glad ya found that line loose.No need to worry about the TB lines. If your car is cold, little will leak. Clamp them off before you pull them if you'd like. Place a rag under the TB to catch drips. It'd be a good time to plug them lines together and make the TB bypass. Yeah you have to take a part the intake.
Race Director
Joined: Jun 2004
Posts: 13,961
Likes: 707
From: WI
For me it made the car easier to work on and look nicer. You can route the hose to not crawl across the passenger side valve cover. It may help make some HP but not much if any. From people posting TB temps, it seems to lower the TB from 200° F to 100° degrees. Making the air intake cooler. You'd never have to worry about your TB dripping coolant again when you work there. 
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