Will engine run without intake duct?
Thread Starter
Burning Brakes
Joined: Feb 1999
Posts: 1,157
Likes: 3
From: Encino CA
Will engine run without intake duct?
I asked this before but am still wondering. My 95 is occasionally rough while idling at a stop. It seemed that I was able to mostly eliminate this by spraying throttle body cleaner and carefully wiping out the bores and throttle plates (also sprayed into the idle port just below the main bores). Of course this had to be done while the engine was off as I could not figure out a way to get the car to turn over with the duct removed. I tried keeping the electric connectors hooked to the duct while the duct was removed (I think these are MAF and IAT sensors) and also tried disconnecting the connectors. Either way, the car did not seem to want to turn over and I did not "force" the issue.
So is there a way of overriding and getting the car to turn over without the intake duct? I figured I could clean things more effectively while spraying the cleaner into the throttle body while the car is running (the Gumout cleaner even instructs to spray while the car is running).
Thanks.
So is there a way of overriding and getting the car to turn over without the intake duct? I figured I could clean things more effectively while spraying the cleaner into the throttle body while the car is running (the Gumout cleaner even instructs to spray while the car is running).
Thanks.
Instructor
Joined: Oct 2003
Posts: 147
Likes: 0
From: Holbrook NY
Re: Will engine run without intake duct? (DougSilver)
Your car will run without the intake duct - it will even drive without it (but not well). If you wist to start the engine with nothing past the throttle body, go ahead. Not a good idea to try and drive it like that, though. The biggest danger is the most obvious - sucking up dirt.
The C-4 'Vettes will start and limp along with quite a lot of disconnected parts. The computer will go into a special "just get me the heck home" mode.
George
The C-4 'Vettes will start and limp along with quite a lot of disconnected parts. The computer will go into a special "just get me the heck home" mode.
George
Burning Brakes
Joined: Feb 2000
Posts: 824
Likes: 2
From: Camden SC
Re: Will engine run without intake duct? (George West)
Sounds to me like the best thing to do would be remove the Throttle Body, clean the Idle Air Control valve, and the air chamber. I suspect you may be drawing some cleaning fluid through the idle air port thereby cleaning the valve, slightly.
A new gasket set for the entire throttle body is around $7, easy job.
dlmeyers 90 coupe zf6 3 speed shocks
A new gasket set for the entire throttle body is around $7, easy job.
dlmeyers 90 coupe zf6 3 speed shocks
Thread Starter
Burning Brakes
Joined: Feb 1999
Posts: 1,157
Likes: 3
From: Encino CA
Re: Will engine run without intake duct? (Pop Chevy)
No--I do not intend on driving without the duct but I thought it would be more effective to spray the cleaner into the throttle body while the engine was running. If I keep cranking, will the engine eventually turn over without the MAF and other electrical connector and without the duct?
Instructor
Joined: Oct 2003
Posts: 147
Likes: 0
From: Holbrook NY
Re: Will engine run without intake duct? (DougSilver)
Doug,
If you need to "keep cranking", I would stop. The engine should start right up, even with the MAF in your living room. You will, of course, get a "service soon" light. But it should start (in the"limp home" mode) with just a click of the key, just as it normally would. If continued cranking is needed, something else is wrong or disconnected. Did you disconnect the TPS?
George
If you need to "keep cranking", I would stop. The engine should start right up, even with the MAF in your living room. You will, of course, get a "service soon" light. But it should start (in the"limp home" mode) with just a click of the key, just as it normally would. If continued cranking is needed, something else is wrong or disconnected. Did you disconnect the TPS?
George
Thread Starter
Burning Brakes
Joined: Feb 1999
Posts: 1,157
Likes: 3
From: Encino CA
Re: Will engine run without intake duct? (George West)
There are only two electrical connectors that I can see--one is to the MAF and the ither may be the temperature sensor (IAT?). I tried once disconnecting the duct and moving it over to the side while leaving the electrical connectors attached, and I also tried removing the duct and disconnecting the connectors. In either case, I cranked a few times and the engine did not jump to life as it usually does, so I stopped cranking. I tried this a few times but never held the key on more than a few seconds. Are you saying that the car would eventually have started if I held the key on?
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Instructor
Joined: Oct 2003
Posts: 147
Likes: 0
From: Holbrook NY
Re: Will engine run without intake duct? (DougSilver)
Doug,
No I would not say that. It should have started right up. Something else was disconnected, wet, dirty, or needed replacing.
In fact, since I obviously have WAY too much free time, let me try an experiment, hold on .......
..........time passes..........
OK. I disconnected the MAF sensor on my '85 Vette. I reached in through the driver's window and turned the key. It made the sound:
RUFF......RUFF......RUFF....and then it caught.
Usually one (sometimes two) "RUFFS" will start it, so maybe it knew about the MAF sensor being disconnected? The "service" lamp illuminated.
Then I connected it, but removed the rubber coupler, and disconnected the MAT sensor (on the coupler). Same results.
Then I disconnected the TPS. To my surprise, the car started up - and sounded just fine.
It seems like a lot could be broken, and still the engine will start. But I do know that everything has to be perfect in order to go fast!
-George
No I would not say that. It should have started right up. Something else was disconnected, wet, dirty, or needed replacing.
In fact, since I obviously have WAY too much free time, let me try an experiment, hold on .......
..........time passes..........
OK. I disconnected the MAF sensor on my '85 Vette. I reached in through the driver's window and turned the key. It made the sound:
RUFF......RUFF......RUFF....and then it caught.
Usually one (sometimes two) "RUFFS" will start it, so maybe it knew about the MAF sensor being disconnected? The "service" lamp illuminated.
Then I connected it, but removed the rubber coupler, and disconnected the MAT sensor (on the coupler). Same results.
Then I disconnected the TPS. To my surprise, the car started up - and sounded just fine.
It seems like a lot could be broken, and still the engine will start. But I do know that everything has to be perfect in order to go fast!
-George
Thread Starter
Burning Brakes
Joined: Feb 1999
Posts: 1,157
Likes: 3
From: Encino CA
Re: Will engine run without intake duct? (George West)
Thanks for the experiment--I wonder if my 95 should react the same. By the way, if you get a "service" light and then reconnect things, does the light go off and reset itself?
