My LeSabre won't start when it is outdoor and cold. It will start in a cold garage just not outside. I have replaced the fuel pump, fuel filter, all the plugs and the plug wires. It runs good except when it is cold. I have to pump the gas and eventually it fires up. Once going it will start easily the rest of the day. As long as it is in the garage it is fine. I did test for spark at the plugs and the module and there is spark. I also checked the fuel injectors and they are working too. This is a mystery to me. I hear lots of talk about the sensors but is there anyway to know without changing them one by one?

Not reallly...

There are many things that have to happen..
When you first turn start your car usually pre injects fuel at the start for a cold start. Apparently thats not happening unless if fires and quits. If it doesnt fire a bit and quit that would be a Computer problem.

One sensor (MAF) checks for air flow.
Another (IAT) intake air temp checks for air temp.
Another (ECT) checks for a cold engine.

The computer deduces from these sensors what to do.

The car seems to think its warm when it isnt, so I would suspect a temp sensor unless theres a fuel flow problem.


Good Luck



Edited by: bassasasin

I had an experienced car tech run a diagnostic on the car after a really cold night. The first thing he noticed is the car has NO crank signal so the senor is bad. He also said the ECM said the car was running lean when in fact it was running rich. He mentioned some other techno stuff I don't understand. I'm going to replace the crankshaft sensor and the ECM and see if that doesn't fix it. I'll look up the sensors you mentioned in your reply too. Thanks!

The first thing he noticed is the car has NO crank signal so the senor is bad. He also said the ECM said the car was running lean when in fact it was running rich. He mentioned some other techno stuff I don't understand. I'm going to replace the crankshaft sensor and the ECM and see if that doesn't fix it. I'll look up the sensors you mentioned in your reply too. Thanks!


With no CPS Crank position sensor signal.. there is abslolutely no spark, no firing, no ignition. Thats not to say yours gets some signals and they fade away as the engine warms.. but when they do dissappear completely, during a run the engine abruptly, absolutely quits.

I dont suspect the ECM yet.. Perhaps the ECT..

The wild thing about this 1990 LeSabre is when it does start it runs great, gets good gas mileage etc. It is amazing that when the wind is blowing the the temps are below freezing it refuses to come out and play. This car was given to me and was mostly driven in Arizona and now it must endure North eastern Ohio. Perhpas the car wants to go back to the desert. The tech who looked at the car was convinced the computer was bad. He also told me the scanner was reporting NO error codes. Instead the ECM was confused and didn't know exactly what to do. Mind you I'm a pastor not a mechanic so he was talking down to my level. Today we're going to replace the ECM and the CPS and see what happens.

The ECM is an easy thing if you can get a cheap one..Junk yard.
THe CRankshaft sensor usually throws a code to the computer. But often it throws a Camshaft code.


However, You did say you had spark at first post.

Checkin for Fuel starvation. If you spray starting fluid (ether) (Ive done WD40) in the engine when the engine very cold does it start.. fire whatever. This tells you you have a fuel problem and not a ignition or Crankshaft sensor problem and you can take a different course.
Fuel pulses do come from the ECM.


Divide an conquer.


In the samelogic can you check for spark when the engine is very cold.


Ignition modules under the coil pack get cold too. Short out spark, quit etc. If you do the junk yard run.. get one of those too off a wrecked car.. a smashed car was running..



Good Luck


Edited by: bassasasin

This car will not start or even sputter when cold. In fact it backfires and smells like gas. I didn't get to replacing the ECM yet but I plan too. I got a new one for $80. I'm thinking the module might be bad and if this doesn't fix my problems I'll be off to the junk yard. Since the car was a freebie why night put some work and money into it. It only has 80K for mileage and I hope to baby it for at least 100k more!

What you just said. tells me you may have ignition problems.. Meaning the crankshaft sensor or ignition module is still a focus..ECM wont hurt still.


Rev Bass


Edited by: bassasasin

ECM is replaced along with the crankshaft sensor and still the car will not start when cold. I sprayed starter fluid into the intake and this had no effect. I guess the next step is to look for the ignition module. At what point do you take the car to a Buick dealer? I guess if someone can diagnose the problem I can get the parts and do it myself otherwise I am going to have to let it sit until warmer weather comes.

Edited by: davchrwoo

Were you able to divide and conquer? If there was spark the spray would have fired a bit..


Im going to assume you proved ignition problems.. somewhat.


The ignition module is under the coil pack. Its flat and the coil pack usually screws onto it. You could get some very hot water in a jug and after the car was cold outside pour that hot water there and warm it up alot. Maybe even 2 gallons.


Theres lots of possibilities..If its not a module its wiring.. and wire checks are necessary. But Im still on a module.


I have recently read some interesting info yesterday... Leaking injectors will cause a hard to start when cold condition... they leak when cold.. which would give you a rich condition.. thats what I learned..But you said no spark when cold.. But we are chasing spark right now. .


Personally I would never go to a dealer. They are good trouble trackers butget paid for it. I like the challenge. hang in there.





I am..

my 89 lesabre did that years ago,changing the coil pack,fixed the problem right away.maybe you should check toward that.Idid160000k since and had no other problem with the car up to now.the price you paid for that car sure is worth a little investment.

Update. Huge snow storm hit cleveland burying my Buick. However, one day it started covered with a foot and a half of snow on top of it. I was shocked. I let it sit over night and now I'm back to the same problem. The crank and poof of a backfire and no start. We're looking into the module and the injectors now.

Cleveland... I just bought a car from there.. .Friday 2/16.

Wouldn't suspect the injectors yet.. You can pull a plug and smell for gas when it refused to start.. Google "worn spark plugs" to read them.

Get that ignition module swapped out from a junker. Or you could just take it out, warm it up in the house and put it back in. That would check for "starts when warm".
Also just thinking of a scenario. If you turn on the ignition and wait for 10 minutes before you crank it and flood it, just the electrics of the module might warm it up OR get some HOT water on it.
Close that chapter.

Odds are better that its an item and not a wire.

Also chasing that Crank sensor possibility, pour some very hot water on the harmonic wheel sensor area. Its about at the 3 o'clock position way down there. You may need a hose for that.

Good Luck



Edited by: bassasasin

I had that problem twice with my 91. The first time I replaced the sensor in the intake and that fixed the cold start problem for at least a year. The I had to replace the coil packs, one set would crap ut when it was cold.

Final Chapter...I replaced the module and after lots of cranking the car started. However, the car back fired whenever I hit the gas hard and the idle was a bit rough. I left the car out over night and in the morning it wouldn't start. I was disappointed. I drove to Mr. Goodwrench at a local dealer and asked about having them look at the car. Instead, they brought one of the mechanics in to talk to me and he suggested I replace the ignition coils since I'd already eliminated everything esle. So i went that morning and replaced the coils for $70. Last night was real cold and when I got up it was only 15 degrees. The car fired instantly without hesitation! Eureka! This part was the suspect part from the beginning. I guess you live and learn. Thanks for you help!
Edited by: davchrwoo

Wow... Reminds me when I couldn't get into a place. Started banging on the door.. no answer... finally called a person to come down and open it up..
Seems the door opened in the other direction.

The good thing now is the education too.


Bass

Edited by: bassasasin

i've been having the same problem with my 90 lesabre. today i tried they idea about spraying some starting fluid to see if i'm getting fuel, did not start. then i checked for spark at the spark plug and was surprised to see that i did have spark. this leads me back to the fuel system. could it be the fuel pressure regulator? or injectors? like the other post, when it starts it runs great. any help would be appriciated.

Start a new thread... It would get more attention and we can start afresh.


I think this thread poster had a spark.. but the coil pack fixed it anyway..


A weak coil pack may not fire to the plug while under cylinder pressure.


Good LuckEdited by: bassasasin

If you have spark and fuel it should run. Maybe your timming gear jumped on you. Any backfiring thru the intake while you try to start?

ok, i'll start a fresh thread. thanks

sdsdsd, the thing is i'm not sure it's getting fuel, or it may be getting to much fuel, i don't know for sure. i can smell fuel after i've cranked it and it hasn't started. thats why i asked the question about the fuel pressure regulator. i am pretty sure that the timeing chain hasn't jumped. the car ran great, i parked it , and now it won't start. thanks for the idea though.