What could be the problem with my car??


Asked by Jul 12, 2011 at 08:52 PM about the 1990 Buick LeSabre Custom Sedan FWD

Question type: Maintenance & Repair

Ok. I have this buick with so many problems it seems.  Recently the check engine light has been on.  I had the catalytic converter taken off and just had a straight pipe ran, i changed the egr valve, fuel filter, air filter, oil change, rebuilt transmission, new coil pack and ignition module, new crank sensor, new o2 sensor, spark plugs are all giving off good spark, the engine only has 113,000 miles on it.  I had the car hooked up to a computer today and it said the tps.  the harness for the tps wasnt holding well so i went to the junkyard and got  a new harness for the tps and spliced the wires well and bought a new tps.  I put it on correctly and the car is still having the symptoms of bad tps.  what could the problem be??? I start a new job tomorrow and I really need my car running!!! Please help!

6 Answers


Put the Cat back on. The engine has to have the back pressure to run correctly. This is by govt mandate to make sure people don't take the cat off.


Ok thanks rob. I'm going to get the cat put back on next saturday. I'll let you know the outcome. Also, I failed to mention that when i had the computer scanned, it also came up with a code 43, electronic spark. I looked it up and it said it could be one of the following: 1.Open or shorted knock sensor, 2. Loose knock sensor, 3. Excessive mechanical noise within engine, 4. Improper or incorrectly installed PROM or CALPACK in the ECM or defective ECM, 5. Intermittent open in the EST line to the ignition module. I ruled out 3 and 4 so it's either the knock sensor or EST line. How do I find the location of the EST line and I found the knock sensor location. I'm going to get the sensor changed since its only $40 and have that EST checked out.

1 of 1 people found this helpful.

I'm not sure what symptoms your car is having, so I can only give an example of a possible cause of the problem. If it is running rough, or not wanting to stay running without gas pedal assistance, you may have a cruddy fuel pump sock (internal) or it's missing. And there is a good chance your gas tank has some trash in it. It's unavoidable. I had a 94 Buick Skylark. We dropped the tank, disposed of gas properly, cleaned tank with fresh gas..replaced fuel pump (it was cooked), sock and filled with a tank of gas. All good.

1 of 1 people found this helpful.

would love to know what was the cause my car is doing the same exact thing..

2 of 2 people found this helpful.

I have a 1995 lesabre 3.8L series 1that had the same issues. As you did I spent alot of money throwing parts at this engine. There was really nothing else to replace except the ecm itself. Cost me $20 at u pull it and 20 mins to install. Car ran great!

1 of 1 people found this helpful.

this may seem like a simple answer but I bought a new gas cap and bingo the light went out on my buick lesabre 2000. good luck.

Your Answer


Looking for a Used LeSabre in your area?

CarGurus has 1,193 nationwide LeSabre listings starting at $799.


Buick LeSabre Experts

  • #1
    Tom Demyan
  • #2
    John Saffrahn
  • #3
    Austin Gaboda
View All

Related Models For Sale

Used Buick Park Avenue
301 listings starting at $4,499
Used Buick Regal
92 Great Deals out of 4,167 listings starting at $3,500
Used Buick Century
595 listings starting at $2,500
Used Toyota Camry
789 Great Deals out of 71,007 listings starting at $1,750
Used Cadillac DeVille
1,260 listings starting at $2,699
Used Honda Accord
535 Great Deals out of 92,557 listings starting at $1,495
Used Mercury Grand Marquis
18 Great Deals out of 1,230 listings starting at $1,900

Content submitted by Users is not endorsed by CarGurus, does not express the opinions of CarGurus, and should not be considered reviewed, screened, or approved by CarGurus. Please refer to CarGurus Terms of Use.