car surges and stalls. help!

I'm runnin' with a 3800 Series I. When I start up my car, half of the time the engine will run pretty rough for about 20 seconds when in park. When in drive, lets say at about 30 mph, the car will kinda hiccup and stall out and then in 1-2 seconds, start running again. Car kinda seems to not really "coast" when I take my foot off the gas either. Gas pedal comes up of course, but it still seems like it's being pressed down. That lasts only momentarily. Occasionally surges really bad when I'm idling also. Maybe a cam sensor? I dunno.

Without us guessing, any way for you to post codes? if any? What year is the car?

It's a 94 Olds 88. I did get a code out of it about 3 months ago, (a different problem was occuring) and it happened to be a bad TPS - replaced that. Then this started happened 2-3 weeks afterwards. It threw a code then: Intermittent Cam Signal.

So was it code 18 or code 41? Both of those are cam codes. Let me know if you can, and tomorrow I can give you the flow chart and/or the schematic. And please specify Royale, LS, or LSS.

If cam sensor is bad, car will run but how well depends on how well the ECU is able to guess cam position.

If you have service records, look back at them and see if you have replaced crank, cam, and oxygen sensors recently. Oxy sensor will not cause this particular problem (it's most likely the cam sensor but you need to verify that) but the point is that based on age and mileage if you have not replaced the combustion and engine management sensors yet -- you soon, soon, very soon will.

Abaddon - it's a Royale. As far as crack, cam, or oxygen sensors being replaced, I have no idea. It's got 107,000 miles on it.

mmmmmk. Read carefully and follow....

NOTE these tests are on the Cam Sensor harness plug

Unplug the cam sensor, turn the ignition on. With a voltmeter, check the voltage between terminals A (brown wire/white stripe) and terminal B (red wire/gray stripe). You should have somewhere in the range of 5-7 volts.

Now check between terminal B (red wire/gray stripe), and terminal C (white wire/black stripe). You should have battery voltage (10.5 - 13 volts).

If you have these correct readings, I would replace the cam sensor.
If these readings are not correct, we need to determine which wire is faulty, or if the ignition module is to blame. Chances are it's the cam sensor. Do these easy checks to be sure.....

Here is the schematic if it helps.....

okay, so i did happen to replace that Cam Sensor about 6 months ago. Car's been running fine, for the most part. It just threw a code a few days ago: Cam Sensor Failure. So I put another one on it, keep in mind that I have also checked the voltage on the harness plug. The readings were fine. Problem fixed the second go around? Nope. Another code was thrown, Intermittent Cam Signal. What could this be? NOTE: My car will occasionally sputter while only accelerating, almost as though it's juuuuust about to stall, but then it'll almost jerk forward a couple times before returning to normal. Of course this doesn't happen often, hence intermittent. It is running better since I replaced the sensor for the second time, but as you can tell, not completely fixed. :/

wellz wrote:

okay, so i did happen to replace that Cam Sensor about 6 months ago. Car's been running fine, for the most part. It just threw a code a few days ago: Cam Sensor Failure. So I put another one on it, keep in mind that I have also checked the voltage on the harness plug. The readings were fine. Problem fixed the second go around? Nope. Another code was thrown, Intermittent Cam Signal. What could this be? NOTE: My car will occasionally sputter while only accelerating, almost as though it's juuuuust about to stall, but then it'll almost jerk forward a couple times before returning to normal. Of course this doesn't happen often, hence intermittent. It is running better since I replaced the sensor for the second time, but as you can tell, not completely fixed. :/

check the wiring to the cam sensor, inside the plug. with a voltmeter connected flex the wires and see if you have an intermittent open. also check the wiring harness plugs at the ignition module and the big connector at the fire wall.

Also, if you cheaped out on the cam sensor (bought a standard "T series" for instance instead of a Delphi, Delco, or such) it may simply have crapped out. You can't cheap out on sensors although the temptation is strong.

Agreed on all that Albert has said. Also, see circuit 451 off of the Ignition Control Module? It's the little ground wire that wraps around the bottom of the IC and connects to the mounting backet stud. Those little bastards have a tendency to rub through and corrode. Can't hurt to check it.......