: Service Emission System - No Acceleration



Big G
08-23-08, 09:03 PM
I have a 96 sedan deVille with 110, 000 miles on it. It's my wifes daily driver. She made a left turn onto our road this afternoon and the accelerator quit working. The display reads Service Emission System. I can turn wrenches, but Detroit lost me with all the electronics.
Any ideas?

Thanks,
Big G

zonie77
08-23-08, 10:08 PM
The sticky right above your post says...Got codes? look here!

Look there. Then come back and let us know what codes you got.:welcome:

Ranger
08-23-08, 10:18 PM
:welcome::yeah:

zonie77
08-23-08, 10:27 PM
Darn, great minds think alike! I like that!:histeric:

zonie77
08-23-08, 10:39 PM
Big G, are you looking at a broken cable? End came off?

zonie77
08-23-08, 10:56 PM
You really gave us nothing to give you help on. Give us a better description than "no accelleration".

Many of the problems with computer controlled engines are the same or similar to older engines.

Big G
08-24-08, 12:19 AM
I don't have a code reader, I suppose I need one, or is there another method?
The car starts fine, goes in gear and idles fine. The Driver Information display says "Service Emission System" and she noticed it as soon as she felt no acceleration after making the left turn. She idled it home and into the garage.
It could possibly be a cable, as there is absolutely no RPM change with the engine running and the pedal pressed. I've had the cover off once and don't remember the fuel delivery actuation setup. I wanted to let the cool down before getting in to it. That will be tomorrow morning. I was curious what loss of acceleration pedal action had to do with the emission system. Is it a sensor, is it a plugged cat, I don't know. I was curious if anyone else had experienced or heard of this particular problem. Thanks all.

Ranger
08-24-08, 12:24 AM
Simultaneously press and hold the OFF and WARMER buttons til the DIC lights up. DTC's will be displayed. In the diagnostic mode high fan =YES and low fan = NO to the prompts. No need for a code reader on a Cadillac.

Even with a clogged CAT you should get SOME RPM response. I'll bet Zonie is right on with the cable. It should be pretty obvious if that is the case.

Big G
08-24-08, 12:30 AM
Thanks Ranger , zonie and the rest of you. I'm on track after I took some advice and did a little reading. I'm playing a gig right now, we;re between sets,. I appreciate the help. I'll check it out in the morning and I'll report back.

misfit6794
08-24-08, 10:53 AM
If the linkage is fine, it might be the throttle position sensor, should set a code.

Big G
08-24-08, 01:03 PM
OK, here is what I found:
PC0603.....Control Module Long Term Memory Reset
PC0741.....TCC System Stuck Off
PC1406.....**I Did Not Find this one**
PC1441..... EVAP System Flow During Non Purge

ALso, when I fired it up this morning, the acceleration appeared fine.
Any thoughts?, like I said, they've lost me with the electronic stuff...
Thanks in advance for your help.

Big G

zonie77
08-24-08, 01:14 PM
When she pressed the pedal did it move?

The cable opens the throttle blade (just like a carb) the TPS tells the computer how far it opened so the computer knows how much gas to feed ( along with a couple of other sensors). The TPS is just a rheostat, a variable resistor, and they are very reliable. It would be strange for it to totally fail, then work fine.

Big G
08-24-08, 01:24 PM
Well I just asked her and she said NO. I was under the impression she pushed it, it worked, but no response...

Big G
08-24-08, 01:34 PM
I did find the PC1406 code.....EGR Valve Pintle Position Circuit.

zonie77
08-24-08, 08:41 PM
Well I just asked her and she said NO. I was under the impression she pushed it, it worked, but no response...

Does that mean it did not move? Then something blocked the pedal or the throttle. Make sure there's nothing rolling around in the car. It's unlikely the throttle itself would have stuck.

CadillacSTS42005
08-24-08, 09:38 PM
egr needs cleaned
its got carbon build up
thats causing the serv emissions message
but it shouldnt cause the car to have absolutely no throttle response...

Big G
08-24-08, 10:31 PM
Does that mean it did not move? Then something blocked the pedal or the throttle. Make sure there's nothing rolling around in the car. It's unlikely the throttle itself would have stuck.

Yeah, like it was locked....My first thought after I asked her this morning was to go look for empties rolling around on the floor, but I found none...
I fired up, drove it got it to op. temp. with no probs. I'll send her to work in it tomorrow and see if my cell phone rings, actually, I'll probably follow her in to work. I'll post back tomorrow evening.
:bouncy:Thanks,
Gordon

Big G
08-24-08, 10:33 PM
egr needs cleaned
its got carbon build up
thats causing the serv emissions message
but it shouldnt cause the car to have absolutely no throttle response...

Yeah, I'm sure it does. Is that still fixed the old fashioned way or is there an easier method now?

Thanks,

Gordon

Ranger
08-25-08, 01:03 PM
Check the Tech Tips section for a post on cleaning the EGR valve.

Big G
08-25-08, 03:14 PM
Check the Tech Tips section for a post on cleaning the EGR valve.



Muchas gracias, Ranger, I'm on it. She drove to work today No Problem, and, there was nothing that could have blocked the pedal travel, nothing rolling around on the floor. Maybe her way of getting back at me because I didn't buy her a new 2500HD for our 25th last week....! No, I can't imagine why the foot feed would totally lock up..

misfit6794
08-25-08, 05:32 PM
Pretty strange. Definetly give the egr a good cleaning, and if that's carboned up, I betting the throttle body is as well, maybe the butterfly got stuck. There's an article in tech tips on how to clean it, very simple, and while you cleaning it, check the harness going into the throttle position sensor to make sure its tight, maybe clean that as well. Oh, and some wide open throttle runs will help that carbon issue.
.
I would take a caddy over a pickup anyday of the year.

Big G
08-25-08, 06:51 PM
Pretty strange. Definetly give the egr a good cleaning, and if that's carboned up, I betting the throttle body is as well, maybe the butterfly got stuck. There's an article in tech tips on how to clean it, very simple, and while you cleaning it, check the harness going into the throttle position sensor to make sure its tight, maybe clean that as well. Oh, and some wide open throttle runs will help that carbon issue.
.
I would take a caddy over a pickup anyday of the year.

Yhanks misfit, unfortunately, her deVille isn't Four Wheel Drive...
...the places that woman takes that car...