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DonovanNorway
11-04-2005, 02:19
After I removed Catalyst. my 95 Sub 6.5 has a high Idle of 1000 rpm all the time. With break, in gear, when warm, when cold. Is there a oxygen sensure that I need to do something about?
moondoggie
11-04-2005, 07:48
Good Day!

No oxygen sensors on either of my 95's.

No change to the idle on the Sub before or after installing JK's exhaust, which is somewhat similar to what you've done.

I've NEVER seen either of my 95 trucks idle this high, except on the Sub - I installed the high idle mod detailed on JK's website, which provides 1075 rpm idle on-demand. As cold as I've seenhere in MN (-30F/-34C), the highest idle I remember is ~ 800 rpm when cold, which drops to ~ 600 rpm warm. Puzzling... :confused:

Blessings!
jspringator
11-04-2005, 13:11
What sensors could he have disturbed changing an exhaust?
Barry Nave
11-05-2005, 03:18
Did'nt happen to change Alt at this time also?
DonovanNorway
11-07-2005, 06:50
Hi
I did not change alt. but today I received to DTC codes of 15 and 48. This is for Engine Coolant sensor and air intake sensor. Another thing that is now happening is that the overdrive will only work for short period, and the transmission will kick down to 3. Starting to wonder if I have a ground problem???
DonovanNorway
11-07-2005, 10:44
I now tried testing the Intake air sensor, and the coolant sensor, and it seems to test like it should according to the book I have. I also tested the crankshaft position sensor and have 4.9 volts on the gray, 4.9 on the yellow with key on.... Not sure if the vibration from the motor would have any differance if a shortage was there.

The high Idle comes and go's sometimes as well.

On the way home from work the overdrive worked for about ten minutes then started shifting down and up several times before staying i 3 for 5-10 minutes, started shifting between overdrive and 3 again so many time where I decided to just put the shifter i 3rd gear for the remainder of the trip.

PLEASE help....
JohnC
11-07-2005, 14:12
I suspect you're on to something with the coolant sensor, or the related wiring. The idle speed will be higher and the TCC will be locked out if the PCM thinks the engine is cold.
JohnC
11-09-2005, 06:31
After mulling this over for a while, I'm not sure if the TCC lockup is controlled by coolant tempature or trans fluid temperature, or both.
moondoggie
11-09-2005, 07:40
Good Day!

Both, on my 95's.

Blessings!
DonovanNorway
11-10-2005, 02:20
Well I went out to my 98 K3500 pickup, ripped out the Coolant sensor, stuck it in the Sub, and yes we have a winner!! So now my pickup is sitting there until the part arrives but feels really good to have the Sub working correctly. Thanks for your help.