: 98 eldo jerking while stopped



dom418
03-28-05, 06:25 PM
Hi all, recently I have noticed that sometimes my eldo starts jerking forward after I have come to a stop while driving, sometimes it goes away but other times it does not until I start accelerating again. My trans fluid is fine and I was wondering what may be some possilbe causes? Thanks

dom418
03-31-05, 09:18 AM
Anyone???

1996deVille
03-31-05, 11:55 AM
Have you had the SS fuel rail replacement as of late? My '96 deVille surges now - after the fuel rail recall... I should've stayed with the plastic, everything was great until then.

As I come to a stop and get off the gas the car pulses forward - is that how your car acts? Mine is most noticeable on a hill, but I can feel the surge at every stop.

dom418
03-31-05, 03:15 PM
The best way to describe it is it feels like I am getting bumped by another car. It jerks forward.

Ranger
03-31-05, 03:51 PM
Have you had the SS fuel rail replacement as of late? My '96 deVille surges now - after the fuel rail recall... I should've stayed with the plastic, everything was great until then.


'98 was not included in the recall........yet. It was '95 - '97. Many of us, myself included, suffered a misfire after the recall. It seems that disturbing old wires in doing the job causes them to break down. Replace your wires with OEM wires and your problem will likely be solved.

dom418
03-31-05, 04:10 PM
I have already replaced the wires, plugs with OEMs and also the FPR. Any other suggestions? Thanks

mcowden
03-31-05, 05:37 PM
I would say clean the throttle body and disconnect the battery for 30 seconds. You can search the forums for this and find lots of info about how to do it. Does it ever idle strangely? Does it start OK? Are there any codes set?

dom418
03-31-05, 06:02 PM
It starts fine and it does idle strange when it is cold. It is not setting off an SES light but I have no other way of checking for codes since I don't have the scan tool.

mcowden
03-31-05, 08:23 PM
It starts fine and it does idle strange when it is cold. It is not setting off an SES light but I have no other way of checking for codes since I don't have the scan tool.

Thankfully you don't need a scan tool. Hold down the OFF and WARMER buttons on the climate panel, or OFF and passenger-side WARMER if you have the analog cluster. Be prepared to write down the codes when they come up. All of the dash lights will come on and then the codes will pop up one at a time. Write them all down and whether they're current or history. Post it here and somebody will probably be able to tell you what's going on.

If it idles funny when cold, I'm betting on the throttle body bore and plate being in need of cleaning and/or an IAC issue. Both of which are easily corrected. Let's start with the codes and go from there.

dom418
04-01-05, 09:16 AM
Ok. The computer ran through all the code types and for each it displayed "no pcm codes..." etc for each type as it cycled through. So no codes are coming up. Do I have to do this when they car is having the problem symptoms or should it have already come up as a past code if there ever was one?

mcowden
04-01-05, 10:31 AM
You can check for codes any time and get the results we're looking for. The codes will show up as either Current or History if there are any. In your case there were no codes, so we're looking for something that's not being tracked by the computer.

I would start by cleaning the throttle body bore and plate. If you search the forums, you will find the procedure described many, many times. It's not very difficult. That will eliminate the crud from the throttle body that could obstruct intake air and cause the weird cold idle you're experiencing. When you're done with that, disconnect the battery for 30 seconds. That will essentially reset the idle air control values so it can compensate for the now-clean TB. If you noticed the accelerator feeling a little sticky sometimes, the TB cleaning will fix it most likely. After that, it's probably time to start listening for vacuum leaks if the problem continues, but drive it and let us know if that did it.

dom418
04-01-05, 10:40 AM
Thank you very much! I'll let you know what I find.

dom418
04-21-05, 11:56 PM
Cleaned the throttle body and no luck. It stopped for a while but came back. I got this code:

IPC U1255 History- Serial Data Line Malfunction

Any ideas???