If you’re in the market for a new or used car, you may have concerns about the GM 4.2 inline six engine. There are numerous common problems with these engines, including problems with the valve seat and thermal sensor. Other issues are more difficult to detect and have caused far more damage than expected. It is crucial to understand what these typical GM 4.2 engine problems are, so that you can properly diagnose your vehicle’s needs.
GM 4.2 inline 6 valve seat issue
If you have a GM 4.2 inline 6 engine, you’ve probably noticed that the intake valve seats are soft. This will cause low compression and miss-firing at idle. If you’ve had any of these symptoms, it’s time to get your engine checked. This problem is fairly common and is easily repairable. However, it’s important to check your valve seats if you suspect any of these symptoms.
To determine the proper seat height and position, you should check the valve spring’s tension. If it is too high or too low, you need to recondition it. To check the seat height, measure from the top of the valve seat to the underside of the spring retainer. You may need to install an extra spring seat shim to compensate for the height difference. If you have a worn valve spring seat, you should visit a machine shop to have it repaired.
GM 4.2 inline 6 faulty thermal sensor
When a faulty thermal sensor causes an engine to overheat, it’s time to get it checked out. A thermal sensor is responsible for reading outside air temperature and relaying that information to your car’s dash and rear-view mirror. Despite its name, this sensor is not a high-risk part that will likely require repair. If you suspect your car is suffering from this problem, take a look at the symptoms it may show and contact your local lemon law attorney.
You can check to determine whether your engine has a faulty thermal sensor by following the troubleshooting steps below. To begin, remove the air cleaner cover and air filter. Use a 10mm socket to loosen the hose clamps holding the large expansion chamber, which sits over the valve cover. Next, remove the nut holding the dip stick, and unscrew the two bolts that hold the expansion chamber in place.
GM 4.2 inline 6 smooth idle
Variable valve timing was first featured on GM inline engines. Variable valve timing allows the engine to run at a smooth idle while still producing good power. It is controlled by an onboard computer that evaluates data such as speed, load, and throttle position. A control valve at the front of the camshaft provides oil quantities to the piston chamber. This technology also improves emissions and torque curve. This article will discuss the various benefits of this technology.
When a car has a rough idle, it means that the fuel-air mixture is not right for the vehicle. A rough idle can be caused by many things, ranging from a clogged air filter to a bad spark plug. In addition, an exhaust system problem may be to blame. Only a mechanic can diagnose the problem and solve it. If you have trouble finding the source of the rough idle, you may want to consider replacing it.
GM 4.2 inline 6 needs a 6L80 trans
A GM 4.2 inline-6 engine requires a 6L80 transmission to keep the power up. This transmission is functionally compatible with GM Gen. III+ and Gen. IV engines, but you should always make sure you get the correct model for your engine. Some GM Gen. IV engines do not work well with other transmissions, and may require special computer programming strategies. Here’s why your 6L80 transmission is the best choice for your truck.
The 4L60E had a large ratio drop in the upshifts, while the 6L80E’s drop was narrower. The six-speed GM automatic transmissions, meanwhile, should work well with a 6L80E. Generally speaking, a 6L80 or 6L90E will fit most GM engines. But don’t get one just because it’s more expensive.
First of all, a 6L80 doesn’t need a manual transmission. You can get one of these for under $200. The problem is that you’ll need to reprogram your transmission control module, which can cause the engine to misfire. Second, the 6L80E has more durable clutch linings. They’re also warmer to the touch. Finally, they can handle 500 to 600 horsepower more than a 4.2 inline six.
To determine the correct transmission for your GM 4.2 inline 6, you can use your vehicle’s RPO code. This is an identifying number for each vehicle. For example, if your GM vehicle has a 4L60E transmission, the RPO code for the 4L60E transmission is M30. When you need to change the trans, you can use the 6L80 adapter assembly.