[83Hokie]

I thought I had seen this before, but the quick check I don't see any posts

Ideas? Dealer can't see it until Tuesday and, of course, my bumper to bumper expired (months not miles) last week ... probably too early to tell, but drivetrain coverage?

 

[hypurone]

I thought I had seen this before, but the quick check I don't see any posts

Ideas? Dealer can't see it until Tuesday and, of course, my bumper to bumper expired (months not miles) last week ... probably too early to tell, but drivetrain coverage?

Usually a misfire code will set this, I have read that some get it with a battery that is in poor shape.... Got a scanner?

 

[83Hokie]

Usually a misfire code will set this, I have read that some get it with a battery that is in poor shape.... Got a scanner?

A scanner? I'm guessing no, actually pretty sure no. Scanning what? That said, some follow-up. This occurred on the way home today, about a mile of dirt road, probably going 20mph (yeah to fast for dirt, but the car was already dusty and I knew it needed a wash), maybe a tenth from my driveway. I could tell something changes and once I stopped at my mailbox, it really didn't seem like it wanted to go over 15mph down my paved driveway where I usually go faster. So, since I knew it wasn't going anywhere but the dealer, I needed to take some console pieces off for painting, including the shifter cover and the gauge trim. I got all of that off and headed out to get to the dealer. Again, the car wouldn't really get up to speed at all. I figured I might get there by back roads so I continued. In automatic, it really never really got going up hills, barely 10mph. I switched to manual and that helped. Using down hills, I managed to get to about 40mph, but since I knew I had to pull out on the highway for a short period of uphill, I decided to take it back home and let Chevy come and get it. Thinking a little further, I realized a piece I took off had the traction control button on it and that they might want that. So, I go plug that back in and put it back on. I start the car again and whaa laa, back to normal. The dealer says they probably will not be able to tell anything. I guess I'll drive it some this weekend and see what happens. Though I'm kind of glad it is fixed, now I'm wondering what caused it and if it will come back.

 

[CRF8]

scanner for the port beneath the steering wheel to obtain error codes.

 

[83Hokie]

gotit, no I don't had thought about it but never did ... maybe more incentive

 

[hypurone]

gotit, no I don't had thought about it but never did ... maybe more incentive

You could always take it to the nearest auto parts store that has a scanner and have them pull the codes for you, right them down and then clear the codes. Most do it for free... Then you can see if the prob returns and if it is repeatable in any way before wasting the time and $ (if any) at the dealer...

 

[83Hokie]

The auto parts store was about 4 times further than the dealer so I never would have been made it ... I think I am going to invest in one ... any recommendations? That said, I'll probably go later this afternoon for a test drive to see if it got resolved

 

[hypurone]

TI think I am going to invest in one ... any recommendations?

I have always just used whatever tuner I had at the time, which now is my SCT iTSX. I leave it plugged in to the port and can scan via my phone!

But for a non-tuner type just to read, clear and understand what codes are present and less expensive, this one seems to be popular:

Actron OBDII

 

[patriotpa]

If someone scans the codes for you...DON'T let them clear the codes. You'll need them for troubleshooting in case it needs to go to the dealer.

 

[83Hokie]

As I moved it back into the garage yesterday, I noticed the check engine light has stayed on ... I'm thinking that means a code is stored, correct?

 

[hypurone]

Yep. For sure. I wouldn't worry about clearing the codes. If it's a repeatable problem it will store it again and the dealer will have something to go by...

 

[hotrodhoodrat]

This happened to shadow.. they found out it was the foot switch that was going out...

 

[83Hokie]

Ok, here you go guys, what do you think now (I'm going to leave it here for now though this may not be the right section). On Sunday, since they said go ahead and drive and see what happens, I did. Out of the house over to Lowe's, about 10 miles, just fine. Come out of Lowe's, start, groan, there is the error again and a definite reduced engine power. Straight to the dealer, lucked out on traffic with the flashers on a couple of times though since it was Sunday of Labor Day weekend, closed. I parked it and cut it off with the error still showing. Today, it wont duplicate, but they read the code "P2135" ... throttle body, ugh. Dealer says GM won't let them do anything without returning it to stock ... okay, I guess I can see that, I have a Cold Air Inductions CAI and a Tampa Tuning ported throttle body, and one of those wedge spacers. Now my questions are: 1) do I do anything if it doesn't do it again, 2) for people who send their throttle bodies in as a core, they are scr3wed aren't they? I kept mine 3) do I try it one piece at a time? 4) these pieces are advertised as not causing codes, what gives?

 

[hypurone]

The electric motor in the throttle body may be bad or having problems, the throttle body blade could be binding in its bushings etc etc. That is the only thing I readily see as being able to set a code.... I would put the OE unit back on first and test....

There is the possibility that with the larger bore of the TB, you are getting slower air speed thru the MAF and it is changing the frequency at which the MAF is reporting to the ECM...

Usually this only comes into play when you change the ID of the intake tube with FI mods but coupled with the larger TB who knows....

 

[83Hokie]

The electric motor in the throttle body may be bad or having problems, the throttle body blade could be binding in its bushings etc etc. That is the only thing I readily see as being able to set a code.... I would put the OE unit back on first and test....

Okay, I'll restore to stock and see where to go from there. By a blade binding does that mean I need some carb cleaner or something to spray it with?

There is the possibility that with the larger bore of the TB, you are getting slower air speed thru the MAF and it is changing the frequency at which the MAF is reporting to the ECM...

Larger bore? You mean because of the porting, not because of a larger mm, correct? Because I just had the stock one ported is all.

Usually this only comes into play when you change the ID of the intake tube with FI mods but coupled with the larger TB who knows....

I have no idea what that means haha

 

[hypurone]

The electric motor in the throttle body may be bad or having problems, the throttle body blade could be binding in its bushings etc etc. That is the only thing I readily see as being able to set a code.... I would put the OE unit back on first and test....

Okay, I'll restore to stock and see where to go from there. By a blade binding does that mean I need some carb cleaner or something to spray it with?

There is the possibility that with the larger bore of the TB, you are getting slower air speed thru the MAF and it is changing the frequency at which the MAF is reporting to the ECM...

Larger bore? You mean because of the porting, not because of a larger mm, correct? Because I just had the stock one ported is all.

Usually this only comes into play when you change the ID of the intake tube with FI mods but coupled with the larger TB who knows....

I have no idea what that means haha

Porting "usually" enlarges the opening of the stock TB, thereby increasing the diameter, thereby affecting the flow rate/speed of the air moving thru the intake tract, possibly affecting the MAF sensor frequency getting reported to the ECM... Now if they didn't put in a larger TB blade and only taper bored it to the original blade... well we don't want to get into that as you may not like the answer....

FI - forced induction....

 

[83Hokie]

Porting "usually" enlarges the opening of the stock TB, thereby increasing the diameter, thereby affecting the flow rate/speed of the air moving thru the intake tract, possibly affecting the MAF sensor frequency getting reported to the ECM... Now if they didn't put in a larger TB blade and only taper bored it to the original blade... well we don't want to get into that as you may not like the answer....

FI - forced induction....

I'm kind of not liking that its not working now, so I'm not sure your answer would make me any happier or madder (and I'm not ready to blame the TB yet, because I don't know enough yet, but if I recall, it was done by Tampa Tuning, but I have to check) ... okay, got it on the FI, that didn't register at first.

 

[hypurone]

I'm kind of not liking that its not working now, so I'm not sure your answer would make me any happier or madder (and I'm not ready to blame the TB yet, because I don't know enough yet, but if I recall, it was done by Tampa Tuning, but I have to check) ... okay, got it on the FI, that didn't register at first.

Any chance the wiring connector is not fully seated or the wiring itself is damaged or burned etc?

Fingers crossed for ya that the stock TB and clearing the code resolves... Machining a moving part that is electronically controlled needs to be done with the utmost care and cleanliness. May be just one of those things and something got in there or the shaft is just binding now for some reason... Hopefully there is some warranty on the Tampa Tuning unit if it is bad...

 

[Chapel]

Is the ECU tuned? With those mods, I would think that you'd need a tune. SOme people get away without needing one. But you have a CAI, ported TB, and Power Wedge spacer which changes the angle of the TB. Your code is TPS sensor voltage correlation. So it could be something like a connection. You say you drove it thru a lot of dirt and dust...maybe some made it's way into the engine bay. Have you ever power washed your engine at a car wash? Maybe some moisture got in the connection ports. But we know it is a problem with the sensor...or something causing the sensor to not read correctly. And my money is on the spacer. I say take it off and see what happens. If no change then take the TB off, replace it with the stock one, and see what happens. And invest in a DTC reader. They're actually quite fun especially the ones that can datalog.

 

[83Hokie]

Is the ECU tuned? With those mods, I would think that you'd need a tune. SOme people get away without needing one. But you have a CAI, ported TB, and Power Wedge spacer which changes the angle of the TB. Your code is TPS sensor voltage correlation. So it could be something like a connection. You say you drove it thru a lot of dirt and dust...maybe some made it's way into the engine bay. Have you ever power washed your engine at a car wash? Maybe some moisture got in the connection ports. But we know it is a problem with the sensor...or something causing the sensor to not read correctly. And my money is on the spacer. I say take it off and see what happens. If no change then take the TB off, replace it with the stock one, and see what happens. And invest in a DTC reader. They're actually quite fun especially the ones that can datalog.

No tune on anything, was trying to avoid it and not mess with anything related to the warranty. I was under the impression, those mods wouldn't affect anything, but I guess that's not correct. I live on a dirt road for now (they are supposed to be paving it this month or next). I do a pretty good job of keeping the engine bay wiped out and I have never power washed the engine. I have been really busy, so its just sitting in the garage for the moment. I think I'm going to return it to stock all the way first and see how it goes. If nothing is wrong, I'll start adding back on. My rational is if it does it in stock configuration, then I can go straight to the dealer again. If I still have a mod on it, I would have to go take it off before going back to the dealer. DTC reader is the same as the scanner / tuner CFR8 / Hyperone mentioned for checking codes, correct? I'm planning to get one of those soon.