View Full Version : EFI light and stalling: 89 classic: long post

11-24-2006, 03:06 PM
Not long ago, I cleaned the stepper motor after the following symptoms:
1. Vehicle stalling at or when coming to a stop. Will sometimes not start up to ten minutes afterwards.
2. Idle often either too low or too high, often up as much as 3000-4000 RPM when in idle or drive at a stop. When accelerating and then easing up on the accelerator, vehicle either stalls or almost stalls.
3.Dimming (pulsating) dash lights and headlamps when activating windshield washer fluid and wipers. The radio does not work and before it stopped working, it would go on and off, similar to a loose connection. I have checked the connections behind the radio on the interior and everthing looks good.
4. EFI light is activated. I know the O2 sensor sensors and mass airflow meter will cause the light to be activated but can't remember the others?

Distributor has been completely rebuilt using OEM Lucas parts. Baseplate assembly was stuck before rebuild causing the dustributor rotor arm not to spring back into place causing idle problems. Timing is adjusted correctly and alternator tests fine. Thanks in advance.

11-27-2006, 01:29 PM
clean battery posts,check out put on the alt. if the running problem was not corrected when you replaced the s.motor i would think about the fuel filter.
replace your o2 sensors,maybe causing a rich mixture.
check your plugs ,and low tension for correct placement.marc

11-29-2006, 01:43 PM
I just cleaned the battery posts and and reinstalled. All grounds are tight and clean. The plugs were replaced recently and the vehicle ran much better but after a few weeks it went back to the way it was before. A few of the old plugs were black and oily. All leads are clean and in correct order. I would appreciate if you would give me a step by step on how to test the alternator and fuel pump? I had an auto parts store test the alternator and they said it was ok. I'm pretty sure the O2 sensors need replaced since I can hear rattling in the catalytic convertors. Thanks for your help.

Paul Grant
11-30-2006, 07:09 AM
If you hear rattling in your cats, it's not the O2 sensors causing it, it's the cats themselves. Buy a Catco 6905 and have it welded in by a good exhaust repair shop. The cat can be had on Ebay for less than $50.

Another thing, a bad cat won't be the cause of the EFI light as it is downsteam from the O2 sensors and therefore wouldn't be able to trip the lght. I'd be willing to bet that along with a cat you need an O2 sensor on that side of the exhaust.

11-30-2006, 12:14 PM
Should I have any problems if I take a different route other than the OEM O2 sensors? I am thinking about buying the Bosch sensors.

Mike Koch
11-30-2006, 01:41 PM
Rovers North has ProLine oxygen sensors at $129.95 each.


http://www.roversnorth.com/store/p-4814-oxygen-sensor-3539l-rr-clc-discovery-i.aspx (http://www.roversnorth.com/forums/../store/p-4814-oxygen-sensor-3539l-rr-clc-discovery-i.aspx)

Have a great day,


11-30-2006, 07:14 PM
Check the throtle position sensor. If its not working properly it could stall the engine and/or accelerate the idle. Good luck.

12-01-2006, 03:22 PM
have you checked the air gap on your dizzy after the rebuild?
also if it ran good after the plugs were changed and then re occurred,makes one think of a fuel problem,to rich could lead you to a temp sending unit,dimming lights may be a bad ground (engine)left side of engine? i think.hows your battery? marc