# P2135/Throttle Body issues



## ownerof2011cruze (Sep 8, 2018)

Yeah I got to enjoy one of the many benefits of having and driving a Cruze too, that of spending quality time with my tow truck driver. And it's all because of the hard work put in by GM's Chevy engineering team to decide to code the tune for GM vehicle PCMs to put vehicle into Limp Mode when a 2% difference is detected between throttle body position sensors. It was so funny that I forgot to laugh. Gotta love that P2135 DTC and Reduced Engine Power Limp Mode safety feature. (Well not so much on Saturday when I was having an intense need for a restroom while stranded on the side of a busy highway. Oh the joy of a high fiber diet.) Gosh and as an added bonus there's no TBPS replacement kit available for the Cruze throttle body 55565489, so the lucky Cruze owner gets to buy a new TB and enjoy spending yet more time under the hood. Not an excessive amount, however, as it's easy to change out the TB. Well at least I think that a new TB is needed as neither GMPartsDirect, AutoZone, Oriellyauto, Advance Auto, or NAPA offer a TBPS replacement kit. Then again my silly problem beyond being out $130 for a tow fee, may be that my beloved Cruze may actually need a replacement Accelerator Pedal/Sensor assembly part no. 13252702. Well I'll inform this thread after I fix it. Ta-Ta for now. Cheers .
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1-8-2019 > All good. Bought New throttle body on Amazon for $91.45. 

https://www.amazon.com/gp/product/B004JBI5Z8/ref=oh_aui_detailpage_o01_s00?ie=UTF8&psc=1

Installed easy-peasy. Torque screws to 71 inch-pounds. Ensure intake manifold bolts torqued to 15 foot-pounds. Reconnect TB,O2S1,BootPSI sensors. Tighten hose clamp holding intercooler-charge tube to TB. I used a short length of 1.75"-2.125" mountain bicycle inner tube rubber as a grommet over the Throttle Body's inlet air connector tube so Intercooler-Charge Tube connection is less likely to suck in unmetered air. Lubed bicycle inner tube grommet using a small amount of talcum power. PCM relearned new TB position sensor output quickly. Drove Cruze to work this AM (Now in morning break.) Getting 38 mpg in stop-go-surface-street commute. Engine coolant temp running max temp of 109°C/228°F. 

 Using Pennzoil Platinum Full Syntheic 5w-30 with a Fram TG10246 filter, Dex-Cool with "Water Wetter", NGK BKR7E spark plugs (More HP, MPG, Smoother running at low rpm idle); previously ported out internal air-dams inside intake manifold. So far intake's internal PCV intact-no oil in intercooler-charge tube or in turbo inlet compressor. Oil consumption issue was solved by use of Bar's Leak VS-1 oil additive in fresh oil change. Ran oil with the seal conditioner for three days over 250 miles as per directions then changed the oil again. No oil consumption since over 2000 miles daily commuting on Dallas freeways.

NBK v-power plugs

https://www.ngk.com/product.aspx?zpid=9349

Gapped at .037" - so far no spark-kernel blow-out while running at 80MPH/2800RPM




Best Good Cheers


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## Blasirl (Mar 31, 2015)

geddinwk said:


> So during the snow storm in south carolina, temps dropped to about 15 degrees in the morning and late evenings. Got the reduced engine power warning, service stabilitrac, blah blah. Engine code was P2135, which could have been the APP, Throttle body, or negative battery cable due to the weather conditions.
> 
> Being the lazy person I am I cleaned everything up and checked the wiring which seemed to help. Weirdly enough, the wiring connector has a slight bulge on the accelerator but not enough to cause a voltage reduction (GM really screwed the pooch on the cruze wiring harness). Reduced engine power warnings still happened about twice per day.
> 
> ...


Welcome Aboard!:welcome:

Potential Causes of P2135 DTC It's been my experience that the wiring connector or "pig tail" on the throttle body gives problems in the form of a poor connection.The female terminals on the pigtail corrode or pull out of the connector. 
Possible bare wire on pigtail shorting to ground. 
The top cover on the throttle body distorted preventing the gears from turning properly. 
The electronic throttle body is faulty. 
The accelerator pedal sensor or its wiring failed. 
The engine management computer has failed. 
The TPS sensors were not correlating for a few seconds and the computer needs to be cycled through its relearn phase to restore active response to the throttle body, or the computer needs reprogramming at the dealer.

Read more at: https://www.obd-codes.com/p2135
 
Don't forget to introduce yourself and your Cruze here.


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## ownerof2011cruze (Sep 8, 2018)

Tools used to replace throttle body screws and allow torquing to 71 inch-pounds:

Harbor Freight 1/4 drive inch-pound torque ratchet
https://www.harborfreight.com/14-in-drive-click-type-torque-wrench-61277.html

Harbor Freight 6" long metric hex ball end 3/8 dive set
https://www.harborfreight.com/7-Pc-38-in-Drive-Metric-Long-Reach-Ball-Head-Hex-Socket-Set-67888.html


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## ownerof2011cruze (Sep 8, 2018)

video of microscope images of faulty throttle body sensor potentiometer causing reduced engine power dtc

https://www.youtube.com/watch?v=C5BEPmFB6cw


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## ownerof2011cruze (Sep 8, 2018)

It's hard for me to believe that I did something correctly, yet by accident I seem to have "trained" my 2011 Cruze ECM part no. 12670036 to properly configure the new throttle body. I thought that was necessary because the engine's long term fuel trim was running high from a cold start in the mid teens 15~ish and the MAP intake manifold pressure was ranging from 50 to 60 KPA while stopped after driving. Yet MPG fuel economy was in the 34 mpg range on the highway when going 65~ish. (I got the number wrong in a previous message.) These symptoms prompted me to think about how to get the ECM to operate the new throttle body in a fashion similar to that of the other one.

I started by removing both the negative and positive battery terminals. (This erased the set status for the I/M Readiness Monitors, but my smog inspection isn't due until November, so there's time to do the drive cycles.)

After waiting 15 minutes, I reconnected the negative battery terminal and then touched the positive cable connector to the hot positive battery terminal and held it on for ten seconds; then I lifted the positive connector off for ten seconds and retouched it for ten seconds. I did this three times, and then I left it disconnected for 15 minutes. After waiting I put both terminals back on the battery and torqued them on.

After doing a battery power ECM "reset" (I was thinking this procedure was probably invalid and some sort of shade tree mechanic urban myth, but it seems to have worked as a prelude to training the ECM for the new throttle body.) I started the engine and let it run at idle for three minutes and then shut it off for one minute; then I restarted and let it run three minutes and shut it off for one minute. I did this six times. Long term fuel trim is now 4.7 at idle, MAP intake manifold pressure is back down to 37-40 KPA while MAF intake air is about 2.3 grams/second with 770 RPM. O2S1 ranges lean rich lean rich from .08-.85 volts and O2S2 is in a narrow range from .68-.72 volts. 

Will update post after test drive.
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After five freeway miles and five city street stop and go miles, the engine cooled down from 106 degrees C to 81 degrees C with heat on full and hood open. Air temp was about 48 degrees F yesterday afternoon. Long term fuel trim just prior to engine shut down was at 6.8, but was as high as 18.5 while waiting for a traffic light after driving for about 8 miles. Up stream or pre-catalytic converter was showing temps of 460~ish at inlet and 390~ish at outlet. Down stream or second catalytic converter showed inlet temp of about 250 an outlet of 200~ish as detected with a laser thermometer. This makes me skeptical of the idea that the extra gas being dumped into combustion chambers is burning in the cats even though the cats aren't showing correct temps. Low voltage on O2S2 makes me think there's too much air. This is probably a result of my having cut away the internal air dams in the intake manifold when I put it on back in July. ( It's internal PCV is still intact, and no oil was observed in the intercooler-charge tube when changing throttle body. ) 

Perhaps I'll pony up the $100 for an upgraded MAF and the $300 for HP Tuner ECM flasher and Tune Editing Software. 

Cheers and Best Wishes to Readers


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