Stalling/hesitating while driving

Hi,

By chance, does the check engine light stay on while the engine is running? If it does, the first suggestion is to have the computer scanned for codes. If you don't have a scan tool, most parts stores will do it for free.

Now, what you described can be the result of several things. In this case, I would suggest checking for engine vacuum leaks. Here is a link that explains how it's done:

https://www.2carpros.com/articles/how-to-use-an-engine-vacuum-gauge

Start with this and let me know what is found. Additionally, let me know if you have noticed any odd sounds from the exhaust or odors.

Take care,

Joe

Okay, it could be a few things. I'm not certain why the A/C would turn off, but anything is possible. Often times if the vehicle goes into a "Limp Mode" or the computer believes it is overheating, things like the AC are automatically shut down. However, when there is something that is causing it to go into limp mode, it would set a code.

The other thing I'm questioning is fuel pressure. That is a possibility if the pump is weak

Regardless, let me know what is found or what they recommend. I should be able to at least tell you if what they are saying makes sense.

Let me know.

Joe

If it is doing the same thing, the new part installed may have failed. You indicated it was a coil. That should set a misfire code, but you said there are no codes.

How long ago was the coil installed? Also, if you have the receipt from the shop, take a pic of it and upload it so I can see exactly what was done.

Let me know.

Joe

Okay, a misfire can be caused by a few different things. However, since it is limited to only cylinder 4, that limits the possibilities.

Things such as a head gasket issue, low engine compression, and a few other things can be an issue. However, let's start easy. Since cylinder 4 is where the misfire has been and the coil has been replaced, let's try switching the cylinder 4 coil with the number 5 cylinder. If the coil is the issue, the misfire will change from cylinder 4 to cylinder 5.

If you look at pic 1 below, it identifies cylinder locations. Cylinder 4 is upfront of the engine/driver's side, so it will be easy to access. Pic 2 shows the coil packs which are located on top of the valve cover.

I highlighted the bolt that holds them in place. What I need you to do is remove the bolt and disconnect the connector (make sure not to mix them up). Gently pull up and wiggle the coil pack and it will come out. Then, simply switch the coil packs between the two cylinders. Again, the wiring must go to the same cylinder where it originated, so don't mix them.

Let me know if you are comfortable doing this. Also, let me know if you can get your hands on a live data scan tool. Often times a parts store will lend one to you.

Take care,

Joe

See pics below.

Hi,

I don't see how it could be related. What is happening with the A/C?

Joe

Hi,

I understand his concerns. Also, I have seen the temperatures you guys are getting. All I can say is wow. I thought 95 was bad. Also, the A/C places a heavy load on the engine, so it doesn't surprise me that it is worse.

Are you able to switch the two coils to see if the misfire changes location? We could have a faulty coil, which should be under warranty.

Let me know.

Joe