Idle issue...input please
Thread Starter
Pro
Joined: Oct 2002
Posts: 586
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From: Schmuckville SA
Idle issue...input please
New 02 and TPS. Idle is fussy as all hell now.... Go figure... New parts,
problem worsens.. IAC has been cleaned out, fuel pump and filter are
recent. Adjusted TPS, set base idle, no go. The 02 was replaced a couple
of weeks ago, the TPS a couple of days ago.. Problem started when TPS
was replaced. What can I do to narrow down the problem?
Few things are worse than a car with hunting/crappy idle.. Rather drive
my commuter and thats pathetic.. Please help.
This is an 85, stock, no mods...
problem worsens.. IAC has been cleaned out, fuel pump and filter are
recent. Adjusted TPS, set base idle, no go. The 02 was replaced a couple
of weeks ago, the TPS a couple of days ago.. Problem started when TPS
was replaced. What can I do to narrow down the problem?
Few things are worse than a car with hunting/crappy idle.. Rather drive
my commuter and thats pathetic.. Please help.
This is an 85, stock, no mods...
Thread Starter
Pro
Joined: Oct 2002
Posts: 586
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From: Schmuckville SA
Just ran out on lunch and replaced the TPS I put in last week...
Same thing, throwing a code 22 and idle will not drop.. Check Engine
light comes on, then goes out, then on again at about 90 second
intervals. Cleared codes, started up and idle jumped up to 1300
and light is back on, code 22 is the only code... Any ideas before
I enter into this years demolition derby? ( I am not kidding)...
This really gets my goat as the original TPS literally fell apart
when I took it off the TB...and the car ran much better with no
light.. I put two brand new parts in and all hell breaks loose..
Only GM...
Same thing, throwing a code 22 and idle will not drop.. Check Engine
light comes on, then goes out, then on again at about 90 second
intervals. Cleared codes, started up and idle jumped up to 1300
and light is back on, code 22 is the only code... Any ideas before
I enter into this years demolition derby? ( I am not kidding)...
This really gets my goat as the original TPS literally fell apart
when I took it off the TB...and the car ran much better with no
light.. I put two brand new parts in and all hell breaks loose..
Only GM...
Pro
Joined: Jun 2003
Posts: 559
Likes: 6
From: OKC OK
Hunting Idle
Were you experiencing the hunting idle before you replaced the tps?
If so my friend, you have a vacuum leak.
I'm speaking from experience. My 85 had a hunting idle that was driving my crazy for a year. What I learned from practical experience and from reading the forum is that sometimes we become too dependant on the ECM to tell us what's wrong instead of following our real world experience.
Shotgunning parts isn't going to help. Drop by your local Autozone or equivalent and get yourself a intake gasket set. Then remove, clean and replace all of the top end gaskets. That will fix your hunting idle.
If so my friend, you have a vacuum leak.
I'm speaking from experience. My 85 had a hunting idle that was driving my crazy for a year. What I learned from practical experience and from reading the forum is that sometimes we become too dependant on the ECM to tell us what's wrong instead of following our real world experience.
Shotgunning parts isn't going to help. Drop by your local Autozone or equivalent and get yourself a intake gasket set. Then remove, clean and replace all of the top end gaskets. That will fix your hunting idle.
Safety Car
Joined: Apr 1999
Posts: 4,623
Likes: 2
From: Ohio
Originally Posted by Unriced
Just ran out on lunch and replaced the TPS I put in last week...
Same thing, throwing a code 22 and idle will not drop.. Check Engine
light comes on, then goes out, then on again at about 90 second
intervals. Cleared codes, started up and idle jumped up to 1300
and light is back on, code 22 is the only code... Any ideas before
I enter into this years demolition derby? ( I am not kidding)...
This really gets my goat as the original TPS literally fell apart
when I took it off the TB...and the car ran much better with no
light.. I put two brand new parts in and all hell breaks loose..
Only GM...
Same thing, throwing a code 22 and idle will not drop.. Check Engine
light comes on, then goes out, then on again at about 90 second
intervals. Cleared codes, started up and idle jumped up to 1300
and light is back on, code 22 is the only code... Any ideas before
I enter into this years demolition derby? ( I am not kidding)...
This really gets my goat as the original TPS literally fell apart
when I took it off the TB...and the car ran much better with no
light.. I put two brand new parts in and all hell breaks loose..
Only GM...
Why all the high blood pressure? You will find what you need to fix this...it's no biggie. I assure you that given the proper description of the symptoms, the details of the car (ie. year, auto manual etc. mileage etc. etc.) you will have adequate feedback from Forum members. Now, obviously it's related to the removal of the "old" working parts, and your install of the new parts. The obvious questions are: a) did you in fact get the proper TPS? The parts stores aren't always right. Yours needs the adjustable one...sounds like you have the correct one. b) are you convinced that it's adjusted correctly? Did you use the jumper harness made for that job, or did you use a home made setup? c) you mentioned that you cleaned the IAC...was it removed? If so, did you follow the factory procedure for resetting it? d) you mentioned that you set the "base idle"...not sure on an '85, but it's usually controlled by the computer. IF yours is, then something changed that required you to use the set screw on the throttle body. d) are you sure that the O2 is properly screwed in, and there's no air getting to it? e) have you driven the car an ample amount of time to have the computer relearn? Triple check your work, have a beer, chill, and give us more details. 
Thread Starter
Pro
Joined: Oct 2002
Posts: 586
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From: Schmuckville SA
Intake gaskets were done less than 2 years ago... along with EGR and temp switch.. I cant imagine thats the problem... No shotgunning here,
I was more or less cleaning up and removed the TPS when I noticed it
was grinding when moving the lever, then the arm came out of it. It did not work after that, hence the replacement..I have also put a vaccum gauge on the car and it looks normal. No jittering or dropping, holds rock solid.. Also, even if idle is bad, the ECM should be able to
at least drop it below 1300 rpms.. Thats my biggest issue now as it is
a new problem that did not previously exist. Will a misadjusted TPS
set a code 22?
I was more or less cleaning up and removed the TPS when I noticed it
was grinding when moving the lever, then the arm came out of it. It did not work after that, hence the replacement..I have also put a vaccum gauge on the car and it looks normal. No jittering or dropping, holds rock solid.. Also, even if idle is bad, the ECM should be able to
at least drop it below 1300 rpms.. Thats my biggest issue now as it is
a new problem that did not previously exist. Will a misadjusted TPS
set a code 22?
Safety Car
Joined: Apr 1999
Posts: 4,623
Likes: 2
From: Ohio
Originally Posted by Unriced
...I was more or less cleaning up and removed the TPS when I noticed it
was grinding when moving the lever, then the arm came out of it. It did not work after that, hence the replacement....Also, even if idle is bad, the ECM should be able to
at least drop it below 1300 rpms.. Thats my biggest issue now as it is
a new problem that did not previously exist. Will a misadjusted TPS
set a code 22?
was grinding when moving the lever, then the arm came out of it. It did not work after that, hence the replacement....Also, even if idle is bad, the ECM should be able to
at least drop it below 1300 rpms.. Thats my biggest issue now as it is
a new problem that did not previously exist. Will a misadjusted TPS
set a code 22?
Thread Starter
Pro
Joined: Oct 2002
Posts: 586
Likes: 0
From: Schmuckville SA
H Rocks, the lever on TPS that slips under the TB lever fell out when I moved it a couple of times. I think I am gonna get the meter out and reset the TPS when I get home. I still think I have a problem. Car has 147k miles and has run very reliably and trouble free up until this incident. I will fill y'all in later... Thanks for the help..
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Le Mans Master
Joined: Dec 2000
Posts: 7,839
Likes: 22
From: San Diego, Ca
Intermittents are usually wiring and the 22 is loss of the TPS signal, so check the connector making sure none of the terminals have backed out and that the wires are intact. You can check the sensor with an analog voltimeter by seeing if the needle fluctuates as you open the throttle. It should be smooth and linear.
The 5 volt reference is gray, so put your meter on it and wiggle the harness. The return is dark blue and shorting it to the reference should set a 21 which would mean that the wiring and ECM are ok. Ground is spliced into the air temp and coolant temp sensors. You're not getting codes for either of those, so it's probably ok. I'd really suspect the connection is funky though. Also, if you disconnected the IAC with it running or readjusted the minimum idle, be sure to depress the accelerator when starting. Let it run for 10 secs and then turn it off. That should get the IAC back to normal.
The 5 volt reference is gray, so put your meter on it and wiggle the harness. The return is dark blue and shorting it to the reference should set a 21 which would mean that the wiring and ECM are ok. Ground is spliced into the air temp and coolant temp sensors. You're not getting codes for either of those, so it's probably ok. I'd really suspect the connection is funky though. Also, if you disconnected the IAC with it running or readjusted the minimum idle, be sure to depress the accelerator when starting. Let it run for 10 secs and then turn it off. That should get the IAC back to normal.
Thread Starter
Pro
Joined: Oct 2002
Posts: 586
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From: Schmuckville SA
Update
We are all good.. Readjusted TPS and we are all set.. Idle is rock solid
and car runs great.. I tell ya, that TPS is sensitive as all hell but it works.
Getting bum parts off the shelf doesnt help either.. Thanks for the help.
We are all good.. Readjusted TPS and we are all set.. Idle is rock solid
and car runs great.. I tell ya, that TPS is sensitive as all hell but it works.
Getting bum parts off the shelf doesnt help either.. Thanks for the help.
Team Owner
Joined: Jan 2003
Posts: 20,316
Likes: 246
From: Summerland B.C. Canada
Originally Posted by Unriced
Update
We are all good.. Readjusted TPS and we are all set.. Idle is rock solid
and car runs great.. I tell ya, that TPS is sensitive as all hell but it works.
Getting bum parts off the shelf doesnt help either.. Thanks for the help.
We are all good.. Readjusted TPS and we are all set.. Idle is rock solid
and car runs great.. I tell ya, that TPS is sensitive as all hell but it works.
Getting bum parts off the shelf doesnt help either.. Thanks for the help.
