Soler TB Install: Infamous P1516, P2101 codes, REP

[Miami_SS]

Three years ago (late 2020), I purchased a Soler Performance TB during COVID-19. I had plans to install it back then but installed Pedal Commander instead (since removed) and life got in the way.

So during Xmas 2023 I had some downtime from work and decided to install the TB. The installation was easy including disconnecting/reconnecting the battery ground cable and performing the throttle relearn procedure as outlined in the Soler directions and all took under an hour.

I started my M6 2SS RS and performed a road test and there was an immediate and noticeable improvement in throttle response.

But within 24 hours the infamous P1516, P2101, and REP (limp mode) codes made themselves present and unexpectedly. As expected, I searched the Internet (including Camaro 5) and quickly found that these symptoms are common on many Chevys (Camaro included) or GM models with a newly installed ported TB and an E38 ECM. Rarely was it reported on straight stock set-ups.

It appears that the ECM "freaks out" because airflow and throttle data received are now out of range of their expected calibrations and the ECM responds by throwing these codes and going into limp mode.

I wasn't even @ WOT - I was cruising and my Camaro would unexpectedly go into limp mode on a city street. I decided to carry my laptop with the latest version of HP Tuners software and performed many DTC resets to clear the codes until I found guidance on the HP Tuners Member Forums.

You have two options:

Uninstall the ported TB and reinstall your stock TB (which I've done as an interim solution)

Change the ECM calibrations (via % increase) for P2101 and P1516 via HP Tuners or similar software. There is no "one size fits all" calibration, you must take an iterative approach until you find the correct % variance for P2101 and P1516 in your car's ECM.

This will require me to reinstall the Soler TB and adjust the calibrations in increments until my car doesn't go into limp mode under cruise and WOT as it does currently. This will require time to determine the proper P2101 and P1516 variances for my car's ECM.

I know that there are Camaro5 members who haven't had any issues with Soler TBs and this post isn't a swipe @ the vendor. I've also contacted them via email. It's just documenting my experience.

I hope this post helps members who experience this PITA!...BTW...Experienced tuners in the HP Tuners Member Forum were also confounded with this issue and sought answers from more experienced tuners in the Forum or from HP Tuners staff.

[Indian_Mack]

Thanks for posting this! A couple months ago I installed the 80mm soler tb.

I had the exact same experience. Had trifecta work up a tune for it, but it didn't change anything. Good to know it wasn't just me, and that there may be a fix. For me, the slight improvement in throttle response want with the headache of tuning it myself, so I sent it back. Hopefully this can help somebody.

[George-CZ]

I've had a Soler TB for several years now with their throttle body controller.
And I haven't met anything like it.
The installation went smoothly - the only thing I paid attention to was about 10 min. pause after opening the door and turn off the ignition until the system has completely turned off. The radio served as an indicator for me.


I then installed the TB, plugged in the TB controller and uploaded a datalog which I sent along with my fuel map to my tuner for correction.

I uploaded a new tune, the car has noticeably improved and everything is perfectly fine.

[Miami_SS]

Originally Posted by George-CZ

I've had a Soler TB for several years now with their throttle body controller.
And I haven't met anything like it.
The installation went smoothly - the only thing I paid attention to was about 10 min. pause after opening the door and turn off the ignition until the system has completely turned off. The radio served as an indicator for me.


I then installed the TB, plugged in the TB controller, and uploaded a datalog which I sent along with my fuel map to my tuner for correction.

I uploaded a new tune, the car has noticeably improved and everything is perfectly fine.

Hi George,

We communicated many years ago on Camaro 5 when I had a different tag. Yes, you have mentioned many times that your Soler installation went well as well as others making similar statements. All I can say is that your tuner probably made adjustments to the %variance in P2101 and P1516 channels in his tune and didn't say anything to you.

If you have HP Tuners software you can access these channels to adjust % variance. The base variance is 6%.

I didn't think about this before but I suspect that P2101 and P1516 are the suspects behind throttle controllers like Pedal Commander and Vitesse shutting down Camaro 5 members' stock throttle bodies when set too high. The E38 (Gen5 Camaro) ECM freaks out because the airflow and throttle calculations are out of range for the ECM to calibrate and it trips these DTCs similar to some ported TBs.

As I mentioned previously, from what I read on the HP Tuners Members Forum, members have had to tweak these percentages (usually upward) until the call no longer goes into REP (aka "limp") mode. This is an iterative process because depends on your mods.

The more mods you have, the more tweaking until you find the desired %variance that the ECM likes and won't throw you into REP.

Once you have this dialed in - then I'm sure it's much easier than doing this the first time and trying to locate that P2101 and P1516 sweet spot.

For instance, I upped my P2101 and P1516 settings to 10% and my car wouldn't start!...dead as a door knob!

I had to rewrite the stock file back to my ECM with the factory settings just to get the car to start. So, I know that setting these variances at 10% will freak my ECM on starting because I suspect the ECM isn't telling the TB to open at that % on start-up.

As another Camaro 5 member stated and I'm paraphrasing - "At some point, it ain't worth the headache with all these DTCs just to accelerate a little quicker."

Also, keep in mind that if the throttle body porting is done incorrectly it will screw up your airflow and throttle calibrations, and your ECM will freak out and put you in REP mode.

From my research, Chevys with the E38 (Camaro Gen 5) ECMs are the most finicky and tend to freak out the most and drive folks up a wall!

It appears that an ECM is either mod-friendly (higher tolerances) or not straight out of the factory.

Remember P2101 and P1516 were intentionally coded into E38 ECM software to prevent non-calibrating equipment from operating in your engine and potentially blowing it up during the warranty period and costing GM $$$. They are there for a reason and doing their job.

I've been out of warranty for about 7 years now and only had a Z28 MAF mod until recently and installed high flow cats, 3" exhaust with 4" exhaust tips. I had no problems until the Soler Ported TB installation this Xmas, that's when my ECM freaked out and constantly threw the car into REP mode even while cruising at 25 mph on a city street.

[IMG]"C:\Users\jysap\OneDrive\Pictures\Screenshots\ DTC Jan 01 2024.png"[/IMG]

[gtstorey]

The ETC test are also there to kick it out if it thinks there might be a difference between what the driver is asking for and what the throttle control is supplying to prevent a runaway vehicle.

[Miami_SS]

Originally Posted by gtstorey

The ETC test are also there to kick it out if it thinks there might be a difference between what the driver is asking for and what the throttle control is supplying to prevent a runaway vehicle.

Yep, if I didn't have HP Tuners software (one of the best mods u can purchase for the $$$ spent) to get a better understanding of the nannies built into E38 ECM software internally. I'd be chasing ghosts like so many in the past when we didn't have access to E38 software and its internals.

Since having HP Tuners software (2+ yrs now) I've been way more knowledgeable in how these ECMs communicate with the car's sensors and controllers, especially after modding.

[George-CZ]

Originally Posted by Miami_SS

Hi George,

We communicated many years ago on Camaro 5 when I had a different tag. Yes, you have mentioned many times that your Soler installation went well as well as others making similar statements. All I can say is that your tuner probably made adjustments to the %variance in P2101 and P1516 channels in his tune and didn't say anything to you.

If you have HP Tuners software you can access these channels to adjust % variance. The base variance is 6%.

I didn't think about this before but I suspect that P2101 and P1516 are the suspects behind throttle controllers like Pedal Commander and Vitesse shutting down Camaro 5 members' stock throttle bodies when set too high. The E38 (Gen5 Camaro) ECM freaks out because the airflow and throttle calculations are out of range for the ECM to calibrate and it trips these DTCs similar to some ported TBs.

As I mentioned previously, from what I read on the HP Tuners Members Forum, members have had to tweak these percentages (usually upward) until the call no longer goes into REP (aka "limp") mode. This is an iterative process because depends on your mods.

The more mods you have, the more tweaking until you find the desired %variance that the ECM likes and won't throw you into REP.

Once you have this dialed in - then I'm sure it's much easier than doing this the first time and trying to locate that P2101 and P1516 sweet spot.

For instance, I upped my P2101 and P1516 settings to 10% and my car wouldn't start!...dead as a door knob!

I had to rewrite the stock file back to my ECM with the factory settings just to get the car to start. So, I know that setting these variances at 10% will freak my ECM on starting because I suspect the ECM isn't telling the TB to open at that % on start-up.

As another Camaro 5 member stated and I'm paraphrasing - "At some point, it ain't worth the headache with all these DTCs just to accelerate a little quicker."

Also, keep in mind that if the throttle body porting is done incorrectly it will screw up your airflow and throttle calibrations, and your ECM will freak out and put you in REP mode.

From my research, Chevys with the E38 (Camaro Gen 5) ECMs are the most finicky and tend to freak out the most and drive folks up a wall!

It appears that an ECM is either mod-friendly (higher tolerances) or not straight out of the factory.

Remember P2101 and P1516 were intentionally coded into E38 ECM software to prevent non-calibrating equipment from operating in your engine and potentially blowing it up during the warranty period and costing GM $$$. They are there for a reason and doing their job.

I've been out of warranty for about 7 years now and only had a Z28 MAF mod until recently and installed high flow cats, 3" exhaust with 4" exhaust tips. I had no problems until the Soler Ported TB installation this Xmas, that's when my. ECM freaked out and constantly threw the car into REP mode even while cruising at 25 mph on a city street.

[IMG]"C:\Users\jysap\OneDrive\Pictures\Screenshots\ DTC Jan 01 2024.png"[/IMG]

If there is no problem with the OEM TB, have you checked the TB hardware itself? Or if it is under warranty, then exchange?

Throttle actuator control motor may be faulty.
Or throttle actuator - bad electrical connection...
it can short circuit somewhere.

A quick thought.

[Miami_SS]

Originally Posted by George-CZ

If there is no problem with the OEM TB, have you checked the TB hardware itself? Or if it is under warranty, then exchange?

Throttle actuator control motor may be faulty.
Or throttle actuator - bad electrical connection...
it can short circuit somewhere.

A quick thought.

Hi George,

I have an update. After putting stock TB back on my Camaro, doing a TB relearn via HP Tuners software, and driving for 1+ hr to recycle the ECM, codes P2101 and P1516 are no longer appearing as DTCs. I didn't remove the ground cable from the battery but will do that to make sure that the ECM memory has been completely wiped clean. I will also perform a crank relearn (in addition to another TB relearn) to make sure that my Camro's ECM throttle, airflow, and spark are in alignment with my reinstalled stock TB.

In addition, Mike@Soler Performance has offered a new TB even though my current TB is out of warranty since it was purchased in 2020. Give Soler Performance bravos for customer service and standing behind their product!

I will install the new ported TB from Soler Performance upon receipt and report my findings in a few weeks.

As I mentioned previously, this is not a Soler Ported TB issue alone. Gen5 E38 ECMs have a reputation for being "finicky" when it comes to ported TBs or devices that potentially impact airflow and expected throttle
postions as I discovered during my internet research.