I recently bought a 94 LeSabre and am having a few issues with it. First, sometimes when I am slowing down, the Check Engine Light comes on. I took the car to Autozone, and there scanner wouldn't link up right, so I have no idea what the codes are.


Second, the car misses and stutters at rpms above idle. I just replaced plugs, wires, pcv valve, valve cover gaskets, and fuel filter. The car still does it. It does this both in park and while driving. In park, if I rev the engine up, the engine acts like it misses, and then catches up, misses and catches up again, and will just keep doing that. Any ideas will be greatly appreciated.

 

Sounds like ignition, but you've replaced the plugs and wires. I guess I would check the (3) coils. If you don't have equipment, buy one replacement and switch it until the problem goes away. It's unlikely that all three have gone bad at once. Other possibilities include the crankshaft position sensor, but you're guessing without the scanner.


Incidentally, in many newer cars, the engine computer will notallow revsabove 3500 RPM in neutral, but that doesn't seem like what's happening here.


If the scanner "wouldn't link up" you may have a more serious problem. I think that you don't have the current OBD II, so maybe the guy at Autozone didn't have the older OBD equipment. But if there's something wrong with your car's computer, it could be an expensive PIA. Maybe you need to go back to the seller as soon as possible.


Edited by: MrBSS

 

I spent some time looking around under the hood yesterday afternoon and found a vacuum hose that wasn't connected and in pretty bad shape. I replaced it, and the "Park" problem went away. The bad news is that even now, when driving a constant speed above 40-45 mph, the car vibrates pretty bad. If I accelerate, it goes away, and if I take my foot off the gas, it goes away. I am thinking this might be the torque converter clutch, but I'm not 100% sure. Any help with this portion.

 

Oh, the OBD on the car is not the old version, that you just sitck the jumper into and the light will flash with the ignition on. It has what I think is the OBD II trapezoid connector, and when Autozone hooked up the scanner, it came up saying LINKING...., and then said a comm error.

 

the link error is bc u have what is referred to as a hybrid obd. az czn run a scan tool if they use their cp9145. it just need power. illl bet the guy used the cp9135 which relies on power from the obd port. urs needs aux power(cig lighter).

 

Thanks for the info. on the scan!

 

The scanner wouldnt link up because you needa OBDI reader on a OBDII connection.. Its a specialized cable. (Blue I believe). I call it a OBD I.5..


I believe over 1500 rpm the timing circuit changes to use sensors.


BEST check for sparkover is uphill under loadin overdrive. or with brake hard on indriveway, or water spray or put the Plugs at .035..In other words under load. IF that is it. ONLY. #1 Bad FuEL (85octane or below) Fuel pressure low, filter clogged, contaminants (water in gas, etc). 2. Wires,Plugs,sensor, grounds,etc 3. COIL Pack, Ignition Module, Fuel Injectors (check plug soot color). CRANKshaft sensor (controls the injectors and Ignition). If without load and intermittent missfire.


NOTE CAMshaft is the advanced timing circuit. (No spark advance)


BAD PLUG wires AGAIN..Cracked plug?for a test of that or spray with water. or put the plugs at .035. Butput them back.


I agree With MrBSS.. on RPM while sitting still.