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gardinerbowen
06-03-2007, 10:24 PM
My 1995 LT-1 has a problem as soon as you slip it into gear it will go up and down from 700 - 1000 rpm's any idea's?

JimN
06-03-2007, 10:35 PM
Look for a loose ground at the rear of the motor, a loose MAP, TPS or IAC plug. If the ECM is mounted low, next to the motor, remove the hose going from the MAP sensor to the throttle body and make sure there's no liquid in it. Make sure the PCV valve is functioning properly and that the hose is tight, with no leaks.

gardinerbowen
06-12-2007, 02:23 AM
Ok so i went through the whole thing i put new plugs in, I made sure all the plugs are working. checked the throttle body sensor's and they both change when i put a meter to them but im not sure what there ment to read.(as i give it gas)

After i put new plugs in the boat come up with a new problem it will no longer run any higher then 35K RPM's and still at idle will go up and down from 10k to 8k.

What does this mean?(and how do i do it?)
Make sure the PCV valve is functioning properly and that the hose is tight, with no leaks.

ANY IDEAS???

Im kind of new at all of this

gardinerbowen
06-12-2007, 02:25 AM
i mean 800

Sodar
06-12-2007, 11:15 AM
Ok so i went through the whole thing i put new plugs in, I made sure all the plugs are working. checked the throttle body sensor's and they both change when i put a meter to them but im not sure what there ment to read.(as i give it gas)

After i put new plugs in the boat come up with a new problem it will no longer run any higher then 35K RPM's and still at idle will go up and down from 10k to 8k.

What does this mean?(and how do i do it?)
Make sure the PCV valve is functioning properly and that the hose is tight, with no leaks.

ANY IDEAS???

Im kind of new at all of this

Well, if that motor is turing 35,000 rpms (35k), than I would suspect you have got one of the FASTEST LT-1's on the planet. :D


Here is a post from me about my old LT-1 and the steps Jim had me run through. It really sounds like it could be the IAC... you should trouble shoot that first.

Here is the link to that thread: http://www.tmcowners.com/teamtalk/showthread.php?t=7962

JimN
06-12-2007, 11:53 AM
If it still "hunts" for the right idle speed, remove the TPS plug and see if it stops. If not, remove the MAP sensor plug.

First thing to do in any injected motor diagnosis- check fuel pressure and verify that the injectors are clear and getting proper firing signals.

gardinerbowen
06-12-2007, 08:36 PM
Ok so i checked everything, I read this whole thread: http://www.tmcowners.com/teamtalk/showthread.php?t=7962

And thought about testing my IAC

I took it out and turned the boat key to the on postion it then shot out the cone shaped thing i tried to screw it back in and it wouldn't stay. I am guessing this is the problem ?

ANY one seen this before?

gardinerbowen
06-12-2007, 08:46 PM
http://bel.rwu.edu/gbowen429/1_IAC.jpg

This Is a pic of it after poped out....

I can screw it in a bit but it will just pop out again as soon as i turn the key I will post anouther pic of it when i screw it together

gardinerbowen
06-12-2007, 08:47 PM
http://bel.rwu.edu/gbowen429/2_IAC.jpg

this is it screwed together

JimN
06-12-2007, 09:21 PM
If you leave the body connected and turn the key ON, hold the pintle in place while someone else turns the key OFF. It may work, it may not. It came out because the tip is supposed to contact the throttle body housing and that tells the ECM that it's "at zero position" due to the rise in current. It then backs out approximately 11 steps to its key ON position. Personally, I would replace it now but try to re-insert the pintle first.

Was it that clean when you removed it?

Sodar
06-12-2007, 09:46 PM
Gardiner... mine did the same thing. I screwed it back in, reinstalled the IAC, turned the key on and left it for a few seconds, then off, then on for a few seconds, then off and then finally restarted the boat and it was fine.

gardinerbowen
06-12-2007, 11:37 PM
yes it was that clean

gardinerbowen
06-13-2007, 01:01 AM
Gardiner... mine did the same thing. I screwed it back in, reinstalled the IAC, turned the key on and left it for a few seconds, then off, then on for a few seconds, then off and then finally restarted the boat and it was fine.


did this just fix the IAC problem or the whole thing? All the problems i have been having?

gardinerbowen
06-14-2007, 09:37 PM
Ok so an update I put in a brand new IAC and this solved the idle problem untill i give the boat gas as soon as it comes back down to idle the same problem begin's.

It Also added a new problem of after giving it gas the boat will stall out. Sometime it will chatch it self cough and come back other times it will just die?

Please help with whatever you know or however you can? Anything i can test? Im going to throw the towl in soon I really wanted to get it working for the weekend