Engine Power Reduced: Meaning, Causes and How to Fix

When your Chevy, GMC, Buick or Cadillac shows engine power reduced, the car hasn't broken down. Its engine computer has put it in a protective mode, often called limp mode: you press the gas, and the car politely declines.

The message is mostly GM's: 1,857 of the 2,073 federal complaints that quote it on 2010 to 2025 models are GM cars. The Malibu alone has 681, and 436 of those are 2016 to 2018 cars.

Those are the model years GM covers for a failing pedal sensor. We read GM's bulletins and owner's manuals, counted the complaints, and priced the parts that set the message on the GM models drivers ask about most.

What does engine power reduced mean?

It means the engine computer has capped how much power your engine makes, so you accelerate weakly and may not reach normal speed. GM's 2017 Malibu owner's manual puts it this way:

“

The vehicle may be driven at a reduced speed while this message is on, but maximum acceleration and speed may be reduced.

”

The same page says to take your car to a dealer as soon as possible if the message stays on or keeps coming back. So the meaning is protective, not a breakdown: the computer has seen readings it can't trust and limits the engine rather than guess.

The wording depends on your car. Older GM cars print it as ENG PWR REDUCED, as the 2011 Malibu manual does, and GM's own bulletins often write it as Engine Reduced Power.

The 2018 Equinox and 2020 Silverado manuals call it propulsion power instead. Drivers often say the reduced engine power light, but it's a message on the screen in the cluster.

It usually arrives with the check engine light, and the code it stores tells you why. Nissan and BMW word theirs differently, starting with engine malfunction, and we haven't read those makers' documents.

What sensor causes reduced engine power?

Mostly the sensors that tell the computer how far the pedal is pressed, how far the throttle is open and how much air is coming in. GM's bulletins name these, and the code tells you which sensor caused reduced engine power:

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Other guides blame parts that GM's documents don't tie to this message, and the code is a better guide than any of them. Here's each one, with how many of the 1,857 GM complaints mention it:

• Transmission89 complaints mention it.
• Battery or charging67 mention the battery.
• Fuel pump52 mention it.
• Overheating or a misfire24 mention overheating and 21 a misfire.
• Crank or cam sensor15 mention one.
• Oxygen sensor or catalytic converter10 mention an oxygen sensor and 9 a catalytic converter.
• Diesel particulate filter, EGR valve, gas cap or brake switch5, 3, 2 and 2, the filter only on diesels.

A mention isn't a cause. Against these, 267 complaints mention the pedal, and the documents point at the pedal, the throttle and the air path.

Our list of check engine light codes explains how to read yours.

Is it safe to drive with reduced engine power?

Only as far as you need to reach somewhere safe or a shop. GM's manuals allow driving at reduced speed, but they give no speed and no distance, and owners report it cutting in at highway speed.

The 2020 Silverado manual adds that under some conditions propulsion is disabled altogether. Its advice is to try restarting after the vehicle has been off for 30 seconds.

Owners who reported a number describe a hard cap. Of 229 GM complaints that state the speed the owner was held to, the median is 25 mph, and nearly half were at 20 mph or less.

That's a fine speed for a school zone and an alarming one on an interstate, so move right and take the first safe exit. If you also see a flashing check engine light, stop sooner than that.

Why does Service Stabilitrak come on with engine power reduced?

Because it's the same fault, not a second one. GM's coverage letter for 2009 to 2011 Impala pedal sensors says that while it's present the car may also display Service Traction Control and Service Stabilitrak.

The complaints agree: 847 of the 1,857 GM complaints mention Stabilitrak or traction control. If you see them together, treat the extra messages as part of the same problem, not as a second repair.

Three warnings at once can look like the car is reading out everything that's wrong with it. It's one fault, announced three ways.

Why does my Chevy Malibu say engine power reduced?

On a 2016 to 2018 Malibu, usually because the accelerator pedal sensor has failed. GM's special coverage N182188250, a free repair it offers outside a recall, says the pedal still works, but the car enters reduced power, the check engine light comes on and code P2138 is set.

GM repairs it free for 10 years or 150,000 miles, whichever comes first, from the date the car was first put in service, regardless of ownership. That covers you if you bought the car used.

The coverage also includes 2017 and 2018 LaCrosse and 2018 Regal, and GM's own labor time for the pedal is 0.3 hours.

The ten-year clock runs from the day your car was first put in service, so a 2016 Malibu first put in service in 2016 was covered only until its tenth anniversary in 2026, and a 2018 until 2028. A dealer checks your car's date by VIN, and our guide shows where the VIN is.

Other years of the Chevy Malibu say engine power reduced for different reasons, listed oldest first. The number in brackets is GM's document, the one to quote at a service desk:

• 2008 to 2012The throttle body's position sensor, with P2135, P0121 or P0221. GM once repaired it free, but that coverage has run out on every year (coverage 14582A).
• 2019, 1.5 turboThe intercooler duct can come off the throttle body, set codes such as P0172 and P0299, and stall the car. It's an emission recall, made for an emissions fault rather than a safety defect, so if it's still open on your VIN the dealer fixes it free (recall N192271200).
• 2022, 1.5 turboThe same charge-air tube separating from the throttle body; the fix is a retainer kit (bulletin 22-NA-224).

Why does my Chevy Equinox or GMC Terrain say engine power reduced?

Because a pedal connector, a charge-air tube or an iced intercooler cuts the power, depending on the year and engine. Here's what causes engine power reduced on each Chevy Equinox and GMC Terrain, oldest first, so you can find yours:

• 2008 and 2009The throttle body's position sensor. GM's free coverage for it has expired (coverage 14582A).
• 2010 to 2015, 2.4LThe pedal's wiring is pulled tight and damages its plug. GM's fix is a new pedal and a short wiring lead, 1.2 hours of labor (bulletin 16-NA-012).
• 2018 to 2022, 1.5 turboThe charge-air tube slips off the throttle body; a retainer kit holds it on (bulletin 22-NA-224). 2019 models are also in an emission recall that's free if still open (N192271200).
• 2018 to 2024 turbo, only in hard coldMoisture freezes inside the intercooler at 0°F or colder. GM's fixes are a grille cover or shutter, and on the 1.5 a cleaned wastegate valve and a software update (bulletins 18-NA-020 and 22-NA-002).
• 2023 to 2026, 1.5 turboA charge-air hose at the turbo collapses or splits (GM technician note PIP5927E).

The Equinox has 179 complaints quoting the message, and the peak year is 2011 with 33. The Terrain, its twin, has 95.

Why does my Chevy Silverado or GMC Sierra say engine power reduced?

Usually because of the throttle body on older V8 trucks; on newer ones the causes spread out. Here's what causes engine power reduced on each Silverado and Sierra, oldest first, so you can find your truck:

• 2006 to 2014 V8, high mileageCarbon builds up in the throttle body. GM's fix is to clean it and then run the idle relearn, or it comes back (technician note PIP4578B).
• 2008 to 2011 V8The throttle position sensor. GM once covered it free, and that coverage has expired (coverage 11273A).
• 2014, 5.3L V8The throttle position sensor again, with code P16A1; the fix is a new throttle body (service update 13254).
• 2019, 2.7LGel inside the throttle body, with P2101 or P1516; trucks built before a VIN cutoff get a new one (technician note PIP5660B).
• 2019 to 2023, 2.7L or 3.0L dieselEngine wiring rubbed through, which can also cause stalls and no-starts (bulletin 21-NA-149).
• 2020Brake module software, not the engine: Service Brake System, Reduced Engine Power and Speed Limited all show at once, and a reprogram fixes it (technician note PIT5730).

The Silverado 1500's complaints peak in 2020, and several 3.0L diesel owners pair the message with the coolant control valve. GM covers that valve on 2021 to 2023 diesels, but its coverage letter doesn't mention reduced power.

Does engine power reduced happen on Ford, Toyota and other cars?

Yes, though far less often. Of the 2,073 complaints that quote it, 216 are other makes, counted here by maker:

Nearly half of Ford's are F-150 and Super Duty trucks, and 8 of the 23 Super Duty complaints mention a diesel. Most of Toyota's are the Tundra and Highlander.

Not every one quotes a message, because many owners use the words to describe a car that simply lost power.

Where a message is quoted, the wording differs by maker. A 2013 BMW X1 owner quotes ENGINE MALFUNCTION: REDUCED ENGINE POWER, and 2020 Highlander owners describe the check engine light with reduced engine power.

We didn't read Ford's, Toyota's or BMW's bulletins for this, so the documents and parts below are GM's. On any make, the first two steps are the same: read the code, then have a dealer run the VIN for an open recall or coverage.

Is there a recall for reduced engine power?

Not a safety recall on the Malibu, Equinox or Silverado 1500. GM handled it with special coverages and one emission recall, which is why your recall lookup can come back empty while a dealer still repairs it free:

A special coverage isn't a recall, so a recall search won't show it. GM mailed owners about the Malibu pedal coverage in August 2019, and a later buyer may never have seen that letter.

That's why the VIN check at a GM dealer is worth making even when your recall search finds nothing.

What do the parts cost?

The four parts GM's documents name cost $16 to $356 at the counter, depending on the part and the car. The box prices them one car at a time, so you can find yours.

Labor isn't in the box. GM's own warranty times are short, 0.3 hours for the Malibu pedal and 0.4 hours for the intercooler tube retainer, but you'll pay a shop's diagnosis and hourly rate on top.

How do you fix or reset reduced engine power?

By fixing what set it, because a restart only clears it until the fault comes back. To fix reduced engine power for good, work through the 5 steps below, in order:

1. Pull over and restart. Turn the engine off for at least 30 seconds, as the Silverado manual says. If your power returns, drive gently to a shop anyway.
2. Read the code. Every GM bulletin on this starts from the code, and it tells you whether to look at the pedal, the throttle or the air path.
3. Run the VIN with a dealer. A special coverage or an open emission recall may pay for your repair, which is why this comes before you pay anyone.
4. Match the cheap fix to the code. P0299 or P1101 on a turbo: the charge-air tube pushed back on and clipped. P2138: the pedal connector checked for water at the driver's kick panel. P2135 or P2101: the throttle body cleaned before anyone replaces it.
5. Relearn after cleaning a throttle body. GM's bulletin says a cleaned throttle body needs the idle relearn, or the computer keeps compensating for carbon that's gone.

You can also turn the message off by disconnecting the battery or clearing the code with a scan tool, but only until the computer sees the fault again. When the parts come to a quote, our guide to reading a repair estimate shows what to check.

If the steps don't end it, each of these three situations has a next step, and none of them is guessing:

• The scan shows no codeA basic reader sees only generic P0 codes, and GM's manuals send a message that stays on or keeps coming back to a dealer, whose tool reads GM's own.
• The code isn't on this pageLook it up in our check engine light codes list. The repair follows the code, not the message.
• The message came back after a repairAsk which reading the shop tested and what it ruled out. GM tells its own technicians not to replace the throttle body or air flow sensor unless it's damaged or proven the cause.

Common questions

Asked most often

What does reduced engine power mean?

The engine computer has limited acceleration and speed because a sensor reading doesn't make sense to it. GM also prints it as Engine Power Is Reduced, ENG PWR REDUCED on older cars, and some people search it as reduce engine power.

How far can I drive with reduced engine power?

GM gives no distance. Its manuals allow driving at reduced speed and say to see a dealer as soon as possible if the message stays on or returns, so drive only as far as a safe stop or a shop.

Can reduced engine power fix itself?

The message can go away after a restart, and GM's Silverado manual suggests waiting 30 seconds before trying. The fault usually hasn't, which is why GM says a message that keeps coming back needs a dealer.

Can cold weather cause reduced engine power?

On 2018 to 2024 Equinox and Terrain turbos, yes. GM's bulletins say moisture can freeze inside the intercooler at 0°F or colder and cause a reduced power complaint.

Can a bad battery or low oil cause reduced engine power?

We found no GM document that links either to this message, and while 67 of the 1,857 GM complaints mention the battery, a mention isn't a cause. The documents we read point to the pedal sensor, the throttle body, the turbo air path and wiring.

Is there a recall for reduced engine power on a Chevy Malibu?

Not a safety recall. 2016 to 2018 Malibus have special coverage N182188250 for the pedal sensor, 10 years or 150,000 miles, and 2019 1.5 turbo Malibus an emission recall for the intercooler duct.

Prices are ranges compiled in September 2026 for the US market and vary by region, engine and shop rate. Prices from $10 up are rounded to the nearest dollar, so $14.13 reads as $14 and $14.52 as $15. Below $10 they're exact. This article is general information, not advice about your specific vehicle. See the disclaimer.