Nissan QR25DE 2.5L Engine
The Nissan QR25DE engine began production in 2001. As of 2021 the QR25 2.5L engine still remains in many Nissan models including the Altima and Rogue. Given its 20+ year old design the engine has been through a number of updates to improve performance, emissions, fuel economy, and reliability. However, they all share the same base design and QR25DE engine code.
It’s a solid engine all around evidenced by the fact Nissan has been using the 2.5 inline-4 for two decades. No engine is perfect, though, and there aren’t any exceptions to the rule here. In this article, we discuss some common problems with the Nissan QR25DE engine along with reliability, specs, and more.
What Cars Use the QR25 Engine?
Nissan 2.5L I4 QR25DE engines are in the following years and models:
- 2005-2019 Nissan Frontier
- 2002-present Nissan Altima
- 2007-2011 Nissan Altima Hybrid
- 2003-2016 Nissan Murano
- 2008-present Nissan Rogue
- 2002-2012 Nissan Sentra SE-R & SE-R Spec V
- 2002-2020 Nissan X-Trail T30 / T31 / T32
There are also a number of other international models that use the 2.5 inline-4 engine. It’s a little tougher to track down specific years on those, so we did skip over a few models.
Nissan QR25 2.5 Specs
QR25DE engines are a part of the Nissan QR engine family. The letters 25 represent its displacement of 2.5L. D stands for DOHC while the E is for multi point fuel injection. In essence, this is why the engine code for the 2.5 inline-4 is the QR25DE. Specs for the Nissan QR25 engine are as follows:
|Displacement||2,488 cc (2.5L)|
|Bore x Stroke||89mm x 100mm|
|Compression Ratio||9.5 : 1 to 10.5 : 1|
|Torque (lb-ft)||173-180 TQ|
It’s important to note – the QR25DE has been around for 20+ years. As a long running production engine it’s been through numerous updates over the years. The 2.5L engine is actually in its 4th generation now. Despite the updates the base design of the QR25DE remains the same, which is why the engine code also remains the same.
Otherwise, these are pretty standard specs for a modern inline-4 engine. The QR25 uses an aluminum block and head to help keep weight down. Its DOHC design offers solid performance and power. Most Nissan models including the Altima have about 175-182 horsepower. However, output varies from 152-200 horsepower depending on the year and model.
2007+ QR25DE Engine
One major update to the QR25 2.5L inline-4 engine occurred in 2007. A few changes help remedy original issues with the engine while others are to improve power, fuel economy, and emissions. Some upgrades to the QR25DE engine in 2007 include:
- Larger diameter single path intake manifold
- Updated piston crown shape to support higher compression
- Cam profile updates
- Piston, bearing, additional coatings to reduce friction
- Extra engine mount
- Higher rev limit and horsepower
We will discuss an issue with the intake manifold that affects 2002-2006 Nissan Altima models with the QR25DE. The new intake manifold in 2007 helps fix those problems. Nissan also added some coating to essential internal parts to reduce friction. A piston crown update allows the QR25 to use a higher compression ratio.
Nissan QR25DE Engine Problems
A few of the most common problems with the Nissan QR25DE 2.5L inline-4 engine include:
- Exhaust manifold pre-cat
- Intake manifold screws
- Oil leaks
- Timing chain
We will examine these QR25 engine issues in-depth in the rest of this article. Though, it’s imperative we add a few notes before moving along. We’re calling the above problems among the most common. It doesn’t necessarily mean they’re common Nissan QR25DE engine problems in the true sense of the definition. Rather, when failures occur these are a few of the most common areas.
That said, the 2.5L inline-4 offers pretty good reliability overall. With multiple updates and changes over the years Nissan was able to correct a lot of the initial issues. Even newer QR25DE engines are still prone to their share of problems, though. We will do our best to clarify what years and models are most affected. At the end of the article we’ll circle back to this topic and discuss QR25 reliability. For now, let’s move on and discuss the above issues.
1) QR25DE Exhaust Manifold Pre-Cat Material
Alright – starting up with a fun issue on the QR25 engine. The 2.5L QR25DE uses a pre-catalytic converter located in the exhaust manifold. There is still another cat in the exhaust. However, the idea with the pre-cat was to put it closer to the engine. That allows the cat to heat up faster and lower emissions on cold starts. Unfortunately, the QR25 pre-cat material is known to break apart and potentially cause engine damage.
Since it lies so close to the engine some material may be pulled back into the cylinders. Pre-cat material can then damage cylinder walls and cause excess oil consumption problems for the QR25DE (among other potential issues). It’s never good to have foreign materials in the cylinders and possibly mixing into oil and coolant.
Anyways, this problem mostly affects the 1st gen Nissan QR25 engines from 2002-2006. Problems were most common on the Nissan Altima and Sentra. Given it’s been quite a few years most engines with this problem should be “fixed” now. Nissan did issue a service bulletin, but it wasn’t always a true fix. Our main concern would be if any damage occurred in the past, which could compromise long-term reliability and longevity of the QR25DE.
Nissan 2.5 Pre-Cat Symptoms
Symptoms of pre-cat problems on the QR25DE 2.5L engine include:
- Dirty oil
- Oil consumption
- Low compression
- Engine failure
When the pre-cat begins failing you may notice dirty oil or particles in the oil during changes. There really aren’t many symptoms before engine damage becomes a major concern. If oil consumption becomes excessive that means the pre-cat material has likely started damaging piston rings and cylinder walls. From there you may lose compression or run into complete QR25 engine failure.
QR25 Inline-4 Pre-Cat Fix / Replacement
While Nissan did issue a service bulletin it wasn’t necessarily a long-term fix. The pre-cat material wasn’t changed nor was the pre-cat moved further away from the engine. As such, the only true solution is getting rid of the OEM QR25DE pre-cat material or an aftermarket header (exhaust manifold). Headers are pretty inexpensive, so many opt to go this route to get a little extra power too.
Header upgrades are often only $100-200 and install is straight-forward. However, this brings up another potential problem. The QR25 alternator lies right near the exhaust manifold, so heat damaging the alternator is a concern. Look for some sort of heat shield to help protect the alternator, such as this SC Concepts heat shield.
2) Nissan QR25DE Intake Manifold Screw Problems
Intake manifold screw problems is another issue that mostly affects earlier 2002-2006 QR25DE engines. It’s again most common on Nissan Altima and Sentra models. These are also known as the butterfly screws or power valve screws. The engine uses a two-stage manifold with two runners in each primary. There are then 4 butterfly valves (also known as power valves). Each valve has two screws bringing us to a total of 8 butterfly screws.
Over time, these screws may become loose and then are pulled into the QR25 2.5L engine. As with the pre-cat problem it’s never good to have materials like a screw going through the engine. It may cause damage to the cylinder head, walls, or even the pre-cat as the screw exits the engine.
Nissan actually re-designed the QR25DE butterfly screws in 2006, so the issue is mostly 2002-2005 models. There was also a service bulletin from Nissan regarding these failures. As of 2021 we suspect most of these original QR25 engines have a long-term fix by now. However, if you’re unsure it may be a good idea to pull the intake manifold and check the screws.
2.5 Inline-4 Butterfly Screw Symptoms
Unfortunately, there aren’t usually a symptoms before the screw actually comes loose and goes through the engine. A few symptoms of QR25 butterfly screw failure include:
- Malfunction indicator lamp (MIL)
- Rough idle
- Power loss
- Engine damage
As the screw comes loose it’s possible to impact the butterfly valves and air-flow into the engine. This may illuminate the MIL and cause rough idle + power loss. Hopefully the screw is still somewhat in place in the manifold. Otherwise, it’s important to verify the screw didn’t cause any severe engine damage as it went through the QR25 engine.
Nissan QR25DE Butterfly Screw Fix
Again, many 02-05 engines likely already have a long-term solution. Nissan did fix the issues with new screws in 2006. Still, it’s a good idea to double check your intake manifold. If you notice any loose screws then tighten them and apply some Loctite on the threads. You can also source the new screw designs and replace all 8 of the QR25 butterfly screws.
3) QR25 2.5L Inline-4 Oil Leaks
Oil leaks are another common issue on the Nissan QR25 engine. They appear most common on older engines. However, a lot of that simply has to do with age and mileage. Many cars and engines run into oil leaks as they age. Gaskets, seals, etc simply wear down with time and begin cracking. The primary QR25DE oil leak we’re focusing on here is the valve cover gasket.
The valve cover gasket (VCG) is responsible for sealing the gap between the valve cover and cylinder head. This rubber-like gasket is prone to a lot of heat and wears down with age and mileage. Look for potential oil leaks from the valve cover mostly at 8+ years and 100,000+ miles.
Other oil leaks are also possible and do happen on the QR25DE 2.5L I4 engine. Look for potential leaks from the main seals and IVTC solenoid. It’s not an exhaustive list, but those are a few other common areas.
Nissan 2.5 I4 Oil Leak Symptoms
Oil leak symptoms are typically pretty simple. Nonetheless, look for the following signs that may point to oil leak problems on the QR25DE engine:
- Visible leak
- Smoke from engine bay
- Burning oil smells
- Low oil
Visible drops of oil on the ground is a dead give-away that oil is leaking from somewhere. However, minor oil leaks may not even reach the ground. The QR25 valve cover gasket lies on top of the engine. Oil may drip onto hot components and burn off before reaching the ground. In this case you may notice smoke from the engine bay or burning oil smells.
Low oil is another possible symptom, but you should notice one of the above symptoms before. All engines naturally consume some oil, so low oil isn’t always an indication of an oil leak.
QR25DE Valve Cover Gasket Replacement
Valve cover gaskets are a simple and pretty cheap fix on the QR25 2.5L inline-4 engine. As with most oil leaks, it’s an inexpensive gasket causing the oil leak problems. The VCG costs less than $20 and is a straight-forward DIY for the handy crowd. You may find yourself paying an extra $100-200 if you go to a repair shop due to labor.
Other oil leaks on the QR25DE engine can be more expensive to fix. Leaks from the front or rear main seals are also cheap parts, but labor becomes a bigger factor.
4) Nissan QR25DE Timing Chain Problems
Timing chain issues are a hot topic on the larger Nissan VQ35DE V6 engine. It doesn’t appear quite as common on the QR25 engine, but timing chain problems do happen. Chains are common on many modern engines and typically avoid the hassle of frequent timing belt replacements. However, timing chain tensioners are a concern with chain systems. Over time, tensioners and guides can wear down.
This can allow the QR25DE timing chain to stretch or jump a few teeth. It is an interference engine meaning there’s overlap in the area the valves and pistons travel. As such, if timing jumps too far the pistons and valves can actually collide. Not good. You’ll end up with a few bent valves at the least.
Premature failures and problems do happen on the QR25DE timing chain. However, with original engines aging some may be coming close to the point these parts are naturally wearing down. If you’re north of 120,000 miles it may be a good idea to inspect the Nissan 2.5L timing chain from time to time. Some do last 200,000+ miles, but better safe than sorry.
QR25 Timing Chain Symptoms
Symptoms of timing chain, tensioner, or guide problems on the Nissan QR25DE 2.5L engine include:
- Limp mode / power loss
- Poor overall engine operation
Rattling or clunking sounds coming from the engine bay is the main symptom of QR25 timing chain failure. It’s one of the first symptoms many will notice. You may also get the MIL, power loss, and poor overall engine operation. Though, these symptoms typically occur only once the chain has failed and jumped some teeth. The below video is of the VQ35 3.5L V6, but it’s a good example of what a failing chain sounds like.
Nissan QR25DE Timing Chain Replacement
Labor can add up to be pretty expensive if you need to replace the entire chain, tensioners, etc. It does depend on the exact Nissan model and year with the QR25DE engine. Anyways, parts come in around $300-600 and labor can quickly add up to $500-1,000+.
The job isn’t cheap, but it’s better than the alternative of the chain or tensioners failing. Repair bills can get very costly if the chain slips too far and bends some valves.
QR25 2.5L I4 Reliability
Is the Nissan QR25DE 2.5 inline-4 engine reliable? Yes, we believe this engine earns average to above average remarks for reliability. Half the QR25 issues we discussed mainly affect the original 02-06 engines. Nissan has kept the 2.5L engine alive for 20 years for good reason. They’ve also done a good job at improving QR25DE reliability over the years with updates and upgrades.
However, early engines did suffer from many problems that could cause serious damage. Pre-cats, butterfly screws, and timing chain problems can all cause severe engine damage in unlucky cases. Again, Nissan did well updating the engine over the years so these concerns should be minimal for 2007+ QR25 2.5L engines.
A lot of reliability also comes down to maintenance. Ensure you use high quality oils, change fluids on time, and fix problems in a timely manner if/when they happen. Do all of this and the QR25DE can provide great reliability (with a tiny bit of luck on your side). Many QR25 engines live to see 200,000+ miles without many serious problems along the way.
Nissan 2.5 CVT Transmission Issues
CVT transmission problems on Nissan QR25DE powered cars is another important topic. This article has been all about engine problems, but there’s more that goes into overall reliability. Unfortunately, some Nissan’s with the CVT automatic transmissions don’t have the best reputation. Early Altima, Sentra, and another models with the QR25 had a 10 year, 120,000 mile extended warranty for the CVT trans.
Even later models aren’t exempt from running into these transmission issues. Anyways, there’s ton of info on this topic and it’s also a little off-topic to this article. As such, we’ll leave it there for now. It’s simply worth the mention since transmission problems can be a costly fix if outside the warranty period.
What’s your experience with the Nissan QR25 2.5L engine? Are you considering one?
Drop a comment and let us know!
Wanting more power? Check out our Nissan VQ35DE common problems guide