SES Light

**theorangeguy** · 05-07-2013, 03:56 AM

Pulled out of the driveway a couple of days ago and started getting a solid check engine light in my 2000 Trans Am M6. Yesterday I noticed that its being really stubborn to not go into higher RPMs. It's like the car is trying to limit the amount of throttle or the amount of RPMs it can climb to. Last night when I drove it around the block it would accelerate but I had to mash the pedal to the floor and the ses light started flashing. I haven't gotten it scanned yet, but figured I would ask you guys...I'll get it scanned in the next couple of days.

I'm thinking MAF or o2 sensor issues...

FYI...it's got long tubes and ORY.

If it is an o2 sensor can I just delete the code and go? If its the MAF im hoping I can just clean it...i'll post codes as soon as I can.

Im also new to this forum...Im on a few other ones, but found this one while searching this issue on the net...looks like a BA forum with a lot of info

**JayTA98** · 05-07-2013, 04:36 AM

Welcome to the forum. If is the one of the upstream O2 sensor you can't delete it it. You will have to replace it. A flashing SES indicates a misfire. The first step is to get the car scanned so you can see what codes do you have. How many miles on the car? When was the last time you changed the spark plug and wires, cleaned the TB and all the regular maintenance?

Have you looked underneath at the O2 sensor wiring and make sure is not cut or meltdown? When there is a problem with O2 sensors is either a wring issue or they are just old and need replacement.

But like I said scan the codes 1st before you start putting money out. Most auto parts stores will scan it for free.

**theorangeguy** · 05-07-2013, 04:42 AM

Originally Posted by JayTA98

Welcome to the forum. If is the one of the upstream O2 sensor you can't delete it it. You will have to replace it. A flashing SES indicates a misfire. The first step is to get the car scanned so you can see what codes do you have. How many miles on the car? When was the last time you changed the spark plug and wires, cleaned the TB and all the regular maintenance?

Have you looked underneath at the O2 sensor wiring and make sure is not cut or meltdown? When there is a problem with O2 sensors is either a wring issue or they are just old and need replacement.

But like I said scan the codes 1st before you start putting money out. Most auto parts stores will scan it for free.

Car has 88,000 miles on it...it was a one owner car when I bought it about a month ago. It bounced around from auction to auction for over a year with no owners...its in really good shape. Oil was changed @ the dealership I bought it from. I doubt the MAF has ever been cleaned. I havent gotten under the car yet, but I will today and I'll get it scanned today. Its been raining in my neck of the woods for a solid 4+ days so I havent been able to get under it yet.

This is my 3rd Fbody so I was waiting for a sensor to start acting up, just didnt expect one this soon

**theorangeguy** · 05-07-2013, 04:44 AM

Also, the SES doesnt flash until I intentionally try to get it to accelerate hard "which I only did once just to see what it would do". It bogged a little bit and then took off...

**JayTA98** · 05-07-2013, 04:46 AM

Originally Posted by theorangeguy

Also, the SES doesnt flash until I intentionally try to get it to accelerate hard "which I only did once just to see what it would do". It bogged a little bit and then took off...

Understood. Once you get it scanned post the codes and i'm sure we can help you out some more.

**theorangeguy** · 05-07-2013, 04:49 AM

Its been raining a lot in my neck of the woods so I havent gotten under the car yet...but I'll get under it today and/or have it scanned today. I bought the car about a month ago and its got 88,xxx miles on it. The oil was changed @ the dealership I bought it from and the car hasnt been owned in at least a year...it bounced from auction to auction and before that it was a one owner car "looks like a military guy owned it". I doubt the MAF has ever been cleaned, but the engine compartment is spotless so I could be wrong...car is in really good shape with the exception of this one issue im having right now.

This is my 3rd Fbody so I was expecting a sensor to start acting up, but not this soon

**JayTA98** · 05-07-2013, 04:53 AM

Originally Posted by theorangeguy

Its been raining a lot in my neck of the woods so I havent gotten under the car yet...but I'll get under it today and/or have it scanned today. I bought the car about a month ago and its got 88,xxx miles on it. The oil was changed @ the dealership I bought it from and the car hasnt been owned in at least a year...it bounced from auction to auction and before that it was a one owner car "looks like a military guy owned it". I doubt the MAF has ever been cleaned, but the engine compartment is spotless so I could be wrong...car is in really good shape with the exception of this one issue im having right now.

This is my 3rd Fbody so I was expecting a sensor to start acting up, but not this soon

So you just got the car?

**theorangeguy** · 05-07-2013, 04:54 AM

yea, its relatively new "to me". Had a 99 Z28 before this...

**JayTA98** · 05-07-2013, 04:57 AM

Originally Posted by theorangeguy

yea, its relatively new "to me". Had a 99 Z28 before this...

Ok have scanned still but i will suggest you to do a few maintenance things that im sure you are familiar with.
Fuel filter
Clean MAF with MAF cleaner
Check your air filter

There is more things you can do but I will say have it scanned. You could be right and it could also be a sensor that needs replacement.

**theorangeguy** · 05-07-2013, 05:29 AM

It cranks fine, idle's fine, and sounds normal sitting still. It only does this stuff when I put the car under some sort of load. I'll post the codes later today. If it is the o2 sensors, do you recommend using the corvette o2's? I know a lot of guys run those if they have long tubes.

**theorangeguy** · 05-07-2013, 01:02 PM

Got some codes...P0300, P0152, P0135, P0155, P0410.

Update... I deleted all the codes and it drove 100% normal for a few minutes then started doing it again. I got a new C5 corvette o2 sensor I'm going to drop in the passenger side and I'm going to clean the maf...hopefully that will do it...

Any other suggestions would be great.

Thanks

**JayTA98** · 05-07-2013, 02:50 PM

Originally Posted by theorangeguy

Got some codes...P0300, P0152, P0135, P0155, P0410.

Update... I deleted all the codes and it drove 100% normal for a few minutes then started doing it again. I got a new C5 corvette o2 sensor I'm going to drop in the passenger side and I'm going to clean the maf...hopefully that will do it...

Any other suggestions would be great.

Thanks

I will start by cleaning the MAF and run the car and see if it gets better. You are getting codes for O2 sensor on both sides before the cats and one code for O2 sensor after the cat(passenger side). Is very unusual for both O2 sensors to go bad specially before the cat. If the car still running bad after cleaning the maf I will swap the driver's side O2 sensor after the cat(not throwing any codes on this one) with the driver's side o2 sensor before the cat. Drive the car to get the codes scanned again. If the code PO135 is gone that means the sensor is bad, you will get a new code for driver's side but after cat(the bad sensor is there now). You might need to reset the codes and drive the car to see if the new codes appears.

I'm suggesting to swap the old one so you don't install the new one and it doesn't solve you anything. If you don't care for that then You can put this new sensor on Passenger side before the cat. You will have 2 good sensors before the cat and should solve the issue if the sensors were bad. The sensors after the cat tell you if the cat is going bad only. Try this and post results but clean the MAF 1st with MAF cleaner spray ONLY.

**theorangeguy** · 05-07-2013, 03:21 PM

Maf is cleaned...went ahead and cleaned the throttle body too while I was in there. Passenger side o2 sensor had water in the connector because the wire was hanging way too low...I'm gonna wait about an hour and let the connection air dry and then install the new passenger side o2 based on what I've found so far...I'll update when that's done.

**cammed goat** · 05-07-2013, 05:06 PM

You're on the right track so far.

**theorangeguy** · 05-07-2013, 06:15 PM

After doing what I said above, the car runs fine... pretty sure the passenger side o2 was the main issue.

**theorangeguy** · 05-08-2013, 04:51 PM

Threw a catalytic converter code today but it doesn't have cats so that's no biggie...

**JayTA98** · 05-10-2013, 05:31 AM

yup it will throw the cat code if you haven't delete the rear o2 codes. Sounds like you did a good job and solved the issue.

**theorangeguy** · 05-11-2013, 06:14 PM

Originally Posted by JayTA98

yup it will throw the cat code if you haven't delete the rear o2 codes. Sounds like you did a good job and solved the issue.

Out of curiosity, does the cat code mess with the air fuel ratio at all or does it just make the ses light come on?

**cammed goat** · 05-12-2013, 08:14 AM

If it's the upstream, it will affect the air/fuel ratio and trip the light. If downstream, the code is due to the fact the computer cannot keep up with the exhaust flow due to the deletion of the catalytic converter.