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Engine Stumbles When Coasting


creslevi
04-17-2004, 05:37 PM
I HAVE A 94 BUICK LESABRE 3.8 V6 WITH 207,000
MILES ON IT AND ITS THE MOST DEPENDABLE CAR I HAVE EVER OWNED, BUT!!! NOW THE QUESTION ABOUT THE 100,000 MILE MARK THE ENGINE STARTED TO STUMBLE WHEN YOU ARE OFF THE THROTTLE JUST COASTING, I HAVE REPLACED THE PLUGS AND WIRES AND PUT A COUPLE CANS OF OCTANE BOOST 108 THRU IT BUT THAT HAS'NT HELPED, I GET ABOUT 25 MPG AND IT RUNS GREAT WHEN I GET ON IT, OCCASIONALLY IT WILL JUST DIE IN TRAFFIC BUT SO FAR AT LEAST IT RESTARTS AS SOON AS I PUT IT IN NUETRAL AND START WHILE STILL ROLLING, ANY SUGGESTIONS WILL BE APPRECIATED THANKS RICK

tman
04-18-2004, 12:37 AM
WHEN YOU HAVE THE CAPS LOCK ON, IT'S LIKE SHOUTING ON THE INTERNET, AND SHOWS ANGER. YOU DO NOT SEEM ANGRY, SO PLEASE TURN THE CAPS LOCK OFF.

creslevi
04-18-2004, 01:38 AM
Sorry about the caps lock, I am very new at this posting routine and still trying to figure out how it all works.
Rick

tman
04-18-2004, 12:59 PM
Thats cool, sorry I cant help. It may be the coil packs, but I'd send it to a dealer to have them look at it.

btw, congrats on 200,000 miles, these engines last forever if you take care of them! My park has 146000 on it, I'm gonna dance on the side of the road when it hits 150!

public
04-25-2004, 07:55 PM
You may also check the torque converter clutch solenoid.

DGary
04-26-2004, 07:55 PM
That sounds like the same problem I am having with my 94 Le Sabre with 215.000 miles on it. It feels like it is trying to run out of gas and on the freeway, it will quit completely but always restarts fine.

creslevi
04-26-2004, 11:00 PM
Hi
My lesabre has 208,000 miles on it, and also has died a couple timels always while kinda coastin,g never under power or acceleration and it also restarts fine soo far, thats what worries me that maybe the next time it won't !!!??. So far I am stumped as to why ?.
I just hope someone reads this and has a solution, I will do my best to post it here if I find out whats wrong and I hope you will do the same.
Rick

DGary
04-27-2004, 07:27 AM
Do you have your Check Engine Light on at any time? Mine comes on once in a while and then goes out. It has an OBDI system with an OBDII 16 pin interface connection and on OBDI you can jumper pins A and B and get the light to blink the code, however I do not know which pins are A and B on the OBDII plug. I am hopeing to find out so I can see what error code has been stored but to no avail so far. Might be a clue as to what causes the engine to quit.

creslevi
04-27-2004, 01:03 PM
Hi Dgary
I am not certain what the OBDI is or where its located ??. Its been suggested maybe the map sensor is going or the pcv valve or the torgue converter lockup solenoid ??.

This car has allways been so dependable now its scary to not be able to pinpoint a problem !!??.

I have done the wires and plugs and put on a rebuilt Alternater last year plus I put on a rebuilt water pump (now I wish I had paid the extra and bought original pump) because I suspect it of making a funny noise that goes away when you take the tension off the belt.
Its a pretty big job to change the water pump (you have to remove the motor mount)so I am not looking forward to that ?.
my battery was dead in the driveway Sunday (unexpectadly)so I cleaned the cable ends and hope that problem is solved.

I find it pretty difficult to work under the dash anymore (Tooo Old)but I can't really afford to pay a troubleshooter either, But its still the best most comfortable car we ever owned, My wife loved it, (I lost her to cancer last dec/21) Lets hope someone reads these posts and comes up with the solution, everything is soo expensive you really can't afford to start throwing parts at it, at least I can't.
Rick

creslevi
04-27-2004, 01:08 PM
PS Dgary to my last post

Never had the check engine light come on, a couple years ago the security light came on for about 100 miles but went out and has never came on again.
Rick

DGary
04-28-2004, 06:55 AM
There are two computer sustems, pre 96 was the OBDI system and 96 and after was called OBDII, on board diagnostics systems. It takes two different readers to check the codes but with OBDI you could jump two pins, A and B, and it would blink the check engine light to give you the trouple code.

MDEM88
04-30-2004, 11:10 PM
Well guys...Im having a horrible problem with my 92 lesabre...not quite as many miles but getting there. A new battery, 2 new starters, and coil packs, so far....now hes gonna try the camshaft sensor.....wish me luck!!! Car only starts when it wants to....I swear at it..I kick it....still won't start! LOL

DGary
04-30-2004, 11:18 PM
Good luck, camshaft sensor won't keep it from starting, it tells the computer when it is top dead center for fuel, if it is bad, it will inject gas on the compression and exhaust stroke both and knock down the milage but will still run fine.

MDEM88
04-30-2004, 11:29 PM
Good luck, camshaft sensor won't keep it from starting, it tells the computer when it is top dead center for fuel, if it is bad, it will inject gas on the compression and exhaust stroke both and knock down the milage but will still run fine.
OOOP...sorry..I meant crankshaft sensor..LOL Car cranks over...but won't start...intermittently....Im sooo sick of this!!

creslevi
04-30-2004, 11:59 PM
Update
Last weekend my battery was dead for no apparent reason so I checked the cables and sure enough they were ful of electrolisis so I cleaned them and thought that took care of the stumble (missing while cruiseing)but today it was back to missing, since Dec/03 I have had a funny rattleing sound and could'nt pinpoint it and today almost bought a steering pump but thank goodness I listened one more time and sure enough it was coming from the alternator (I put on a rebuilt last Aug. so I had dismissed that, But that was where the noise was coming from, So the parts store gave me another (I let them hear it first)then I smelled antifreeze and the fitting for the bypass hose from the manifold to the water pump was broken (plastic nipple)it was a dealer Item $13.31 if you can believe that !. Does anyone know if a computer diagnosis will pinpoint any problems with all these sensors ie:Cam,Crank,etc. it runs again and has never failed to start, it now has 209,000 miles on it.
I do think it runs better since I cleaned the cables ?? .
I hope someone comes up with a solution soon.
Rick

DGary
05-01-2004, 07:34 AM
I replaced the fuel filter a couple days ago and haven't noticed the problem i was having (stumbling) since, it had been replaced at some time before but no idea when.

creslevi
05-03-2004, 10:22 AM
can anyone describe how to check and or change the crank sensor, Where is it located, how does it work, I am sure enjoying reading all you guys responses on this forum and the sharing of information is just great, it is sure fun to be helpful to someone when you can.
Rick

DGary
05-04-2004, 07:43 AM
When my 96 century had an error code I could check which turned out to be a camshaft position sensor, I went to the public library and looked up the info in the GM manual, it gives detailed info on how to check sensors, locations, and how to check if it is really the sensor or the computer itself.

daddymac6
05-08-2004, 10:19 PM
hi im having same problem with my 94 olds 88 have engine light on but cant pull up and codes it says its obd1 equipped but cant find scan tool for obd1 system with the 16 pin connecter if any one knows how to pull codes please email me @rmarti8@twcny.rr.com thank you.

creslevi
05-11-2004, 01:05 PM
Yesterday I found out I do have the OBD2 system and had a tech check it out, he said the Engine was fine the Stumble was in the Converter, So I had the tranny serviced (Flushed with filter change)$124.95 ! took 1 1/2 hrs, It did not help, so now wonder about the switch on the converter ?.
The Engine had no codes or weak cylinders ! (209,000 miles)Wow.
If it is the converter How does it come out ?. I have been told you are more likely to have trouble with the tranny than the engine, anyone else experience this
Rick

PS
I hope everyone that was kind enough to write me about this either gets a copy of this or reads this post, there's probly a way to do that with this forum, But I don't know how YET.

tman
05-11-2004, 05:14 PM
the engines are built like a rock, but you can kill a tranny quite easily.

dgogley
05-12-2004, 10:04 AM
the engines are built like a rock, but you can kill a tranny quite easily.
If it is in the tranny is this a common problem? I only have 80,000 mi (highway) and mine is doing the exact same thing. I have read posts on other internet sites where people with as little as 30,000 miles are experiencing the same thing.

dgogley
05-14-2004, 06:53 PM
If it is in the tranny is this a common problem? I only have 80,000 mi (highway) and mine is doing the exact same thing. I have read posts on other internet sites where people with as little as 30,000 miles are experiencing the same thing.


Ok guys update, I took my Buick to the transmission shop today. Found out their is a small valve in the transmisssion that wears out, about a $300 job. I will keep to posted if it corrects the bucking, jumping problem

creslevi
05-14-2004, 08:14 PM
After I had my 94 Lesabres tranny, oil & filter changed on this past tue, on wed morning I had to wait about 10 t0 15 seconds for the tranny to build up pressure enough to move the car, its the first time ever that happened, I am told when they flushed the tranny they probly washed out some blocked passages that now lets the oil pressure bleed off during the night ??, The problem is in the torque converter shift electronics ??. Due to age and miles 209,000 a whole different tranny is suggested ? , what do you guys think, It runs real strong with no Slippage when I accelerate and it only bleeds off at night, I guess the OBD2 does'nt have much to say about the tranny ??.It is nice to know the engine is running fine with no codes showing, If it needs a tranny is there any suggestions on the best site to find one, and how much to expect to spend, I am a Widower and just suffered a horrendous financial loss due to theft, So I am between a rock and a hard spot as this is my only wheels, If I am going to change tranny's I have to get my ducks in order beforehand, Could dgogley elaberate a little on this little valve that wears out, and does the tranny have to come out to get to it, I sure don't need this now I just lost my wonderful wife of 50 years in Dec. Thank you for any and all help or advise on this.
Rick

DGary
05-14-2004, 08:44 PM
I think they fed you a line of bull, shouldn't slip at all and no reason for it.
If it didn't slip before you took it in, they are the reason for it now IMHO.

sega
05-17-2004, 10:22 AM
i had this problem with my 92 lesabre and it stopped after i replaced the fuel filter. at one point i let my gas get a littler below quarter tank and it started acting up again, so i used the fuel injector cleaner and it fixed the problem once again.

pcmos
06-07-2004, 09:24 PM
Ok, first of all I have successfully used the pins A and B on the OBD I connector on my old 1992 LeSabre to read out the codes, all of these diagrams including this procedure are outlined in great detail in the two factory shop manuals for the car, which I really recomend. Pin A is a ground line and can technically be interchanged with any ground connector you find under there, but the wire coming out of it will always be black. Once you find the pin on the connector for the ground, the pin right next to it will always be B. So if you can get a peek at the wires coming out of that connector, one of them will be solid black which is the "Pin A" wire, the wire right next to the black one in the same row will be the "Pin B" wire. No matter what there is always only one ground wire on the old pre - 1995 connectors, so once you find that one ground wire the pin right next to it in the SAME ROW will be the pin B, just as my little diagram shows below, I copied this right out of my shop manual.

My manual shows the following:

F E D C B A
G M

where A and B are the pins you need to short between in order to read your codes

I had similar problems on my old 1992 LeSabre but more of a situation where my car would stall out under heavy stopping or on hard turns, so one day I went to my gas station and filled my tank to the brim with 89 octane fuel, and went out for a joy ride late at night with it to make it act up. I Jammed on the breaks, revved the engine, did everything I could think of to make it fail and it simply wouldn't. Then I went home and immediately siphoned the fuel into our other car until I had the lesabre down to just above empty. I repeated the same moves with teh car and I barely got it around the corner before it stalled out. All in all I found out that GM re-designed the fuel strainer and sender assembly on the pre-1995 LeSabre's so I bought the sender assembly and strainer. Unfortunately I got rid of the car for another reason later and never installed them, if anyone wants to get these parts from me i'll sell them cheaply and you can give it a shot.

The car also had a problem where it would lose power for no reason under hot driving conditions, this turned out to be a bad cam shaft position sensor, but it drove me crazy for many years. I would just be driving along on the highway perfectly normally and all of a sudden I would hit the gas only to find that the car had no power and the engine would almost die out. I would let off the gas and accelerate gently and it would get up to speed. One cold winter day I went out with a hair dryer and got the cam sensor nice and warm, turned on the car immediately and boom it was acting up. I had the sensor replaced by a mechanic and never had a problem again.

cswor
08-12-2004, 07:29 PM
i didn't see that you had gotten your problem resolved, so i'll throw in my 2 cents worth: i had a similar problem on a 90 nissan 240sx. in that case it turned out to be a failed/failing 02 sensor. since your codes have been read, they would have probably found that.

3echo9
08-13-2004, 09:50 AM
Well guys...Im having a horrible problem with my 92 lesabre...not quite as many miles but getting there. A new battery, 2 new starters, and coil packs, so far....now hes gonna try the camshaft sensor.....wish me luck!!! Car only starts when it wants to....I swear at it..I kick it....still won't start! LOL

I'd put money on the Crank Pos Sensor. You might as well change the Cam Sensor too. It's only around $30 and it's right there when you change the CPS.

creslevi
10-24-2004, 05:53 PM
After many months and frustrating trials I think I finally solved the stumble problem I posted last mar/apr ?.
about a month ago my check engine light started coming on pretty regularly, So I took it to my local parts house where they do a courtesy scan for you and it said intermittent miss noted and EGR pintel circuit problem.
I took a chance and went to the wrecking yard and bought an identacle EGR for $45.00, (?I think it had 126,000 miles on it) cleaned the mounting surface put it on and no more stumble or miss at all, At least so far needless to say I am very pleased and surprised that that was the problem, I have been tempted a number of times reading the different posts to change this or that and now I am happy I didn't, The car now has 216,000 miles and running strong with no oil consumtion to speak of and hopefully My MPG will improve, Even though I don't really understand exactly how the EGR works from what I do know it could drastically effect my MPG, Thanks to all who took the time to read my posts and respond I hope this post will help someone else in the future, I have a tranny question but I will put it in a new post.
Rick
PS
A new EGR was quoted at $180.00 from the same parts house.

avatar307
10-24-2004, 11:28 PM
You know. After I tilted my engine up 10 degrees to replace the water pump... my TCC Solinoid shudder doesn't seem near as bad. Maybe I tweaked the TCC back into the place or something. LOL Don't ask me, I only know enough about TCCs and automatic transmissions to cause problems.

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