TPS?

[CHL2T]

As stated in another post, the 95 SLS has been acting up. Every time I go to start it it will immediatly stall and start with the loud clicking and tapdance on the foot. I can see the thing doing it when I look under the hood.

Once the clicking is done, and if I wait a few seconds, I can start it by applying the gas about halfway and starting it. Once I have started it in this way, it will continue to start normally.

After less that five minutes after shutting it off, I have to go through the whole procedure again. I personally don't care as I can start anything around here, but since it is my daughters car, I need it it start normally for her.

Any thoughts?

Comments?

Thanks in advance. )

[KHE]

Sounds like the idle speed control motor assembly has dirty contacts in the closed throttle switch portion. Tons of information in the archives on that issue.

[CHL2T]

Could you point me in the direction of the archives? I cant seem to find it.....

Thanks!

[KHE]

Could you point me in the direction of the archives? I cant seem to find it.....

Thanks!

In the upper right corner of the page, below your sign-in name, there is a search field. Search ISC or idle speed control. There is a LOT of information.

[CHL2T]

Replaced the idle speed sensor motor as it was making a hell of a squealing noise as well as the tapdance on the foot and it has had no effect other than eliminating the squeal.

I have tried several times to dredge up some info using search and advanced search but it keeps directing me back to this thread with no other help.

The car still won't start, it will fire up and then immediatly die with no codes other than stall detected.

Any ideas (other than the search function)

Thanks

[adallak]

Can you take a picture of the part that makes that clicking sound?

[CHL2T]

Sure, here is the link..... http://www.oreillyauto.com/site/c/detail/BWD0/EC1403P/02176.oap?year=1995&make=Cadillac&model=Seville&vi=1027796&ck=Search_motor-idle+speed+control_1027796_2975&keyword=motor-idle+speed+control

[Cadillac Jim]

How about the OBD codes?

If it's not the ISC Stepping motor or the TPS, it's another sensor or a sticking throttle cable or cruise control servo. If it's another sensor, the OBD codes will tell us which one.

[adallak]

Sure, here is the link..... http://www.oreillyauto.com/site/c/detail/BWD0/EC1403P/02176.oap?year=1995&make=Cadillac&model=Seville&vi=1027796&ck=Search_motor-idle+speed+control_1027796_2975&keyword=motor-idle+speed+control

That is ISC motor. I think it should be adjusted after installation. I replaced it three times on my 4.9 engine. Once, I even had to shorten the plunger so it would work. Did you touch the minimum air screw on the throttle body? Your throttle body blades can be so dirty that they do not allow enough air in and make the engine stall.

Get access to throttle body. Clean it with carb cleaner and tooth brush. Pay attention to back sides of the blades and the bores. After cleaning you should disconnect the battery for three minutes. I am sure after cleaning throttle body, EGR valve, adjusting per manual ISC motor, your car will run just fine.

[CHL2T]

Sure, here is the link..... http://www.oreillyauto.com/site/c/detail/BWD0/EC1403P/02176.oap?year=1995&make=Cadillac&model=Seville&vi=1027796&ck=Search_motor-idle+speed+control_1027796_2975&keyword=motor-idle+speed+control

That is ISC motor. I think it should be adjusted after installation. I replaced it three times on my 4.9 engine. Once, I even had to shorten the plunger so it would work. Did you touch the minimum air screw on the throttle body? Your throttle body blades can be so dirty that they do not allow enough air in and make the engine stall.

Get access to throttle body. Clean it with carb cleaner and tooth brush. Pay attention to back sides of the blades and the bores. After cleaning you should disconnect the battery for three minutes. I am sure after cleaning throttle body, EGR valve, adjusting per manual ISC motor, your car will run just fine.

Thanks for the response,

Things I have done since the problem started....

1. Removed and cleaned the EGR pintle, Check engine light is now off. (when the car starts and runs....lol)

2. Replaced the Idle speed control motor (unsure of adjustment procedure, will check chilton manual but I am sure there will be no help there)

3. Did a partial cleaning of the throttle body but not a thorough one, will tear the assembly down as far as I can, clean it and report back.

Charged the battery overnight as it was cranking slow and the car fired right up like there is nothing wrong at all. Tried it a minute ago and it's back to the tapdance

And no, I haven't touched the minimum air screw, don't even know where it is...LOL

Edited July 14, 2013 by CHL2T

[CHL2T]

Tore the throttle body out, found that it and the spacer were CAKED with carbon buildup.

Cleaned the living #$@* out of the parts, reassembled and...........

Same thing, still the tapdance fire up and die and still with no codes

[adallak]

Tore the throttle body out, found that it and the spacer were CAKED with carbon buildup.

Cleaned the living #$@* out of the parts, reassembled and...........

Same thing, still the tapdance fire up and die and still with no codes

See, you have had multiple issues, not just one. Check out ISC motor adjustment procedure. 4.9 engine had it , Northstar has it most likely too. You'll be fine as soon as you adjust it.

http://www.cadillacforums.com/forums/cadillac-forum/t-79245.html

When ISC motor is not adjusted properly, the plunger does not move far enough at start up to increase RPM enough, so that cold engine would not stall. That is your problem. I mean your Northstar's one.

Cleaning EGR pintle may be not enough. The diaphragm can be destroyed, the spring may be weak, etc.

DO THIS. Have someone start engine. Push the throttle lever by hand to increase RPM. You will see the engine will NOT stall that way. As it warms up, you can leave the throttle alone.

[Göran W]

Also sounds as if You have a bad battery or poor charge from alternator! Maybe lost a cell in battery?

[CHL2T]

I am at my wits end with this thing. I have tried and tried to get it to start and run consistently to no avail.

After trying to start it twenty times, I was able to get it running by backing the screw on the isc all the way down. It ran rough for about a minte with the isc clicking evey now and again but once it warmed up it would start, run and idle normally. I was able to start and run it several times so thinking that I got it licked, I leave it for a couple hours.

Come back and of course,no start.

Read the link suggested above rgarding the minimum air screw thinking it has to be the thing, tear the trottle body apart again, get to the screw, remove it and install it opposite of factory so I ca get to it once the TB is reassembled.

Back together and still no start! (start, no run)

Still no codes

[adallak]

I am at my wits end with this thing. I have tried and tried to get it to start and run consistently to no avail.

After trying to start it twenty times, I was able to get it running by backing the screw on the isc all the way down. It ran rough for about a minte with the isc clicking evey now and again but once it warmed up it would start, run and idle normally. I was able to start and run it several times so thinking that I got it licked, I leave it for a couple hours.

Come back and of course,no start.

Read the link suggested above rgarding the minimum air screw thinking it has to be the thing, tear the trottle body apart again, get to the screw, remove it and install it opposite of factory so I ca get to it once the TB is reassembled.

Back together and still no start! (start, no run)

Still no codes

Do you have any manuals? Factory service manual? Chilton? I think you do not follow ISC motor adjustment procedure correctly. Now, when you touched the minimum air screw, things could get even worse.

[KHE]

Did you review the ISC motor adjustment procedure? Messing with the minimum air screw did not help matters. What do you mean you installed it opposite of factory??? That would mean the minimum air screw is doing nothing and the engine cannot get enough air to run. Hard to believe that it is even possible to reverse the minimum air screw.

The correct thing to do is to properly install the minimum air screw. Start the engine and depress the closed throttle switch on the ISC assembly to get the ISC plunger to retract fully. Then set the minimimum air screw to the factory specified RPM and LEAVE IT ALONE. Then adjust the plunger on the ISC to the factory specified distance from the stop.

[CHL2T]

Did you review the ISC motor adjustment procedure? Messing with the minimum air screw did not help matters. What do you mean you installed it opposite of factory??? That would mean the minimum air screw is doing nothing and the engine cannot get enough air to run. Hard to believe that it is even possible to reverse the minimum air screw.

The correct thing to do is to properly install the minimum air screw. Start the engine and depress the closed throttle switch on the ISC assembly to get the ISC plunger to retract fully. Then set the minimimum air screw to the factory specified RPM and LEAVE IT ALONE. Then adjust the plunger on the ISC to the factory specified distance from the stop.

By reversing the min air screw, I meant that instead of it having to be adjusted from underneath the throttle body, I can adjust it from the top. It installed and turns just fine.

As for adjusting the ISC, I did it according to instructions found in an earlier post directing me to "cadillac owners" forum.

Once I removed the throttle body and located the Min air screw,(with isc still attached) I noticed the screw wasn't even touching the stop on the throttle and the plunger on the isc was fully retracted but still pushing on the throttle and holding it open

Ugh! Everything that I have had to work on and or fix was "worked over and poorly fixed" by the previous owner!

[adallak]

Did you review the ISC motor adjustment procedure? Messing with the minimum air screw did not help matters. What do you mean you installed it opposite of factory??? That would mean the minimum air screw is doing nothing and the engine cannot get enough air to run. Hard to believe that it is even possible to reverse the minimum air screw.

The correct thing to do is to properly install the minimum air screw. Start the engine and depress the closed throttle switch on the ISC assembly to get the ISC plunger to retract fully. Then set the minimimum air screw to the factory specified RPM and LEAVE IT ALONE. Then adjust the plunger on the ISC to the factory specified distance from the stop.

By reversing the min air screw, I meant that instead of it having to be adjusted from underneath the throttle body, I can adjust it from the top. It installed and turns just fine.

As for adjusting the ISC, I did it according to instructions found in an earlier post directing me to "cadillac owners" forum.

Once I removed the throttle body and located the Min air screw,(with isc still attached) I noticed the screw wasn't even touching the stop on the throttle and the plunger on the isc was fully retracted but still pushing on the throttle and holding it open

Ugh! Everything that I have had to work on and or fix was "worked over and poorly fixed" by the previous owner!

Learning curve... you 'll be fine as soon as you adjust ISC motor and understand how it works.

[CHL2T]

Did you review the ISC motor adjustment procedure? Messing with the minimum air screw did not help matters. What do you mean you installed it opposite of factory??? That would mean the minimum air screw is doing nothing and the engine cannot get enough air to run. Hard to believe that it is even possible to reverse the minimum air screw.

The correct thing to do is to properly install the minimum air screw. Start the engine and depress the closed throttle switch on the ISC assembly to get the ISC plunger to retract fully. Then set the minimimum air screw to the factory specified RPM and LEAVE IT ALONE. Then adjust the plunger on the ISC to the factory specified distance from the stop.

By reversing the min air screw, I meant that instead of it having to be adjusted from underneath the throttle body, I can adjust it from the top. It installed and turns just fine.

As for adjusting the ISC, I did it according to instructions found in an earlier post directing me to "cadillac owners" forum.

Once I removed the throttle body and located the Min air screw,(with isc still attached) I noticed the screw wasn't even touching the stop on the throttle and the plunger on the isc was fully retracted but still pushing on the throttle and holding it open

Ugh! Everything that I have had to work on and or fix was "worked over and poorly fixed" by the previous owner!

Learning curve... you 'll be fine as soon as you adjust ISC motor and understand how it works.

Believe me, I'm trying.....lol

[KHE]

By reversing the min air screw, I meant that instead of it having to be adjusted from underneath the throttle body, I can adjust it from the top. It installed and turns just fine.

As for adjusting the ISC, I did it according to instructions found in an earlier post directing me to "cadillac owners" forum.

Once I removed the throttle body and located the Min air screw,(with isc still attached) I noticed the screw wasn't even touching the stop on the throttle and the plunger on the isc was fully retracted but still pushing on the throttle and holding it open

Ugh! Everything that I have had to work on and or fix was "worked over and poorly fixed" by the previous owner!

The ISC plunger will be touching the throttle and holding it open slightly. If it did not, the engine would nearly stall.

If you have not done so already, clean the throttle body and the plate. I can't remember what the minimum air screw idle RPM is but the engine will be almost stalling at that RPM. That's why the ISC opens the throttle slightly.

You need to depress the closed throttle switch on the ISC and the plunger will retract. Once it is retracted, unplug the ISC and there should be a gap petween the ISC plunger and the throttle plate. Adjust the min. air screw to provide the proper idle RPM, then adjust the plunger on the ISC to the specified gap. Plug the ISC back in and it should be all set.

[CHL2T]

Thanks for the help guys but after discussions with the wife and daughter, we have decided to dump the car and get a newer, less hammered on and reliable Caddy...

If you remember, it was traded for a pos 78 chevy truck that cost me 300 bux so I'm not too torn up about it

[Cadillac Jim]

I would try what KHE says and see if that fixes it. It's just a few minutes, and if it works, you are done. If not, you have lost nothing.

[CHL2T]

I would try what KHE says and see if that fixes it. It's just a few minutes, and if it works, you are done. If not, you have lost nothing.

I have followed every direction, suggestion and procedure that all of you fine folks have suggested......

Tried to start the car this morning and it starts right up but idled like it is only running on two cylinders, after a minute, it smooths out.

Upon trying to give the car gas, it immediatly chokes and dies. After a few more minutes, it will idle, and drive fine but as soon as it cools down it's back to the same thing .

Gonna go look at a couple STS's today one 00 and the other and 03.....anything in particular that I should be aware of on either of these two years other than the obvious block test?

Thanks again guys!

[Cadillac Jim]

Perhpas the FPR, which could quite well be bad on your current car. Lift the hood and see if all the hoses are on the throttle body, and lean over and see if there is a faint smell of gasoline. If the engine is cool, sniff the coolant; the smell of exhaust there is a deal breaker. If the car is cold, start it, let it idle for about 30 seconds and see if it starts and idles, OK, then shut it off. Then, go back to the rear of the car and see of the exhaust has either the smell of fuel (bad FPR) or coolant (head gasket). The smell of coolant at the rear of the car after starting a cold engine for a few seconds is a deal-breaker.

Then, take a test drive. Right after you start the engine, run the OBD codes, and write them down, particularly any CURRENT codes. Then, drive through an OBD cycle as well as the usual test-drives stuff (smoothness, responsive engine, shifts OK, no noises or quirks in the steering or suspension, etc.), and when you get back but before you shut it off, run the OBD codes again, and note any differences, particularly any codes that are CURRENT after a drive that were HISTORY before you started.

Then, unless you have your own OBD code sheet and mechanic, come back here and post your experiences, including both lists of OBD codes. If you are happy with what you have when that's over, I would still have a trusted mechanic go over the car for you.

Don't forget to check the tires for wear, flat spots, obvious repairs that may not hold on the freeway, mismatched tires on the drive axle, etc.

And, get a CarFAX.

[CHL2T]

Perhpas the FPR, which could quite well be bad on your current car. Lift the hood and see if all the hoses are on the throttle body, and lean over and see if there is a faint smell of gasoline. If the engine is cool, sniff the coolant; the smell of exhaust there is a deal breaker. If the car is cold, start it, let it idle for about 30 seconds and see if it starts and idles, OK, then shut it off. Then, go back to the rear of the car and see of the exhaust has either the smell of fuel (bad FPR) or coolant (head gasket). The smell of coolant at the rear of the car after starting a cold engine for a few seconds is a deal-breaker.

Then, take a test drive. Right after you start the engine, run the OBD codes, and write them down, particularly any CURRENT codes. Then, drive through an OBD cycle as well as the usual test-drives stuff (smoothness, responsive engine, shifts OK, no noises or quirks in the steering or suspension, etc.), and when you get back but before you shut it off, run the OBD codes again, and note any differences, particularly any codes that are CURRENT after a drive that were HISTORY before you started.

Then, unless you have your own OBD code sheet and mechanic, come back here and post your experiences, including both lists of OBD codes. If you are happy with what you have when that's over, I would still have a trusted mechanic go over the car for you.

Don't forget to check the tires for wear, flat spots, obvious repairs that may not hold on the freeway, mismatched tires on the drive axle, etc.

And, get a CarFAX.

Thanks Jim,

Before I started dinking with the various intake and idle issues, the first thing I noticed were that the two vacuum hoses to the right of the fpr were off. Thnking that was the original trouble with the stalling, I hooked them back up and the thing still did the same.... The rest as they say is history.

Just a minute ago however, I went out and the 95 started and ran normally so thinking what the heck, I started really romping on the gas To my amazement, I was suddenly surrounded by thick cloud of white smoke. Still thinking "what the heck" I continue romping as my nephew is saying "keep going, it's starting to thin out and only coming from the right now" He also noted that there was quite alot of oil dripping out of the pipes as well. I keep romping till no more smoke or oil and now it seems to run and sound alot better......soooo....now I am again undecided....