I need help diagnosing issues. Back in May I bought a 2010 Infiniti g37 anniversary edition coupe, this is my first car . The car had been in a rear end accident and everything in the front needed to be replaced except the radiator. The previous owner had also done no maintenance except for oil changes, he drove the car about 35k miles from 85k to 115k. Fast forward to August, the car is fixed but has some problems. When the car was getting fixed it got taken to a local shop where they did a transmission flush but the transmission was slipping. It also had every light on the dash but once I got an alignment done all of the lights went away. The car was driving well, except for the slipping transmission. But last week, on my way back on the freeway I heard a pop come from the engine and smoke soon followed. I got a check engine light and turned off the ac, to which the smoke stopped. I then drove it about 15 mins home maintaining 50 mph, but right when I hit the exit the car went into limp mode. I pulled over, turned it on and off and it drove for about a minute. After that it started jerking and the rpms would go up to 3k and down, and I still had no power. When I pulled over I opened the hood and there was fresh coolant on the engine, and the coolant or heater (not too sure) hose in the back of the engine next to the battery had ripped in half. At this point I taped it and drove it home. Then a couple days later, somethings happen and someone in my family decides to take it to a shop that is about 15 miles away. About 5 mins into the trip, the car has the same problem as it did when I hit the exit. It starts jerking, no power, and rpms go up to 3 and back down. The individual proceeds to pour water on the hose, and repeats this 3 times. Eventually the car stops completely and he keeps pouring water on it, when he gets within a mile and a half of the shop. Fluid is coming out of the bottom of the car, you can't turn the car on anymore. There are loud clunks and banging sounds coming from the bottom of the car. He gets it to the shop by pushing it and within 3-4 days they fix the hose and the car can drive again. After the car is fixed, I picked it up from the shop and drove it home about 12 miles. Immediately I could tell that the car wasn't fully fixed. When I would push on the accelerator it felt much lighter/looser than before, it would also take almost 70% throttle for me to get it past 55. The car was still jumpy and felt much slower. When I got home, I let it sit because I didn't want to break it again and drove it the next day. The next day I drove it about 1.5/2 miles and the highest speed that I went was 40. To get to 40mph I had to essentially slam the throttle, it wasn't like this before. I tried using the paddles but the response was much slower than before and was pretty jumpy. When I parked the car I could still smell coolant like as if the hose had popped but the hose was still intact. There was also fresh liquid on the engine bay, but it didn't seem to be coolant. Anyways, I was wondering if someone could help me figure out what's wrong with the car. There are some details that I left out that I could add, but there pretty minor. I can provide pictures, videos, etc. but I just need to know what's wrong with it and if it's fixable.

 

My God what a headache reading this post... (do these schools not teach composition anymore?)... anyway...

Your first mistake was driving the car with a broken coolant hose. As soon as you saw "smoke" (likely steam), you should have pulled over and shut the car down. My guess is the engine was overheating which caused the heater hose connector to give out. This is a known issue for these cars to begin with so any added pressure (overheating) increases the risk. The real question is why it was overheating in the first place. However,

Your second mistake was allowing someone to drive 15 MILES in a car with a known cooling issue/ likely had no coolant in the engine. And, what jackass "pours water on the hose" to get the car to move? The car did everything it could to tell you to STOP (limp mode) before it just couldn't anymore. Yet, you/ they ignored those warnings and still tried to push the car further. "Slamming the throttle" isn't going to do a thing when the car is sick.

My guess, you overheated the engine. The "loud clunks and banging sounds" could be detonation or it could mean a issue with the rotating assemblies (crank/ cams/ etc.). Any number of problems can arise when a engine overheats: warped heads, blown gaskets, cracked blocks, spun bearings, scorched journals just to name a few. Did you ever identify what "fresh liquid" was all over the engine bay? Did you check the oil? Is it clean or milky?

Look, you're young and inexperienced, I get it. We've all been there and ridden on that learning curve. I am not trying to beat you up but at some point common sense has to exist somewhere. The car told you to STOP and you didn't. There could be any number of issues with your car/ engine that will be next to impossible for anyone here to diagnose. Get the car looked over by someone who knows what they are doing and go from there. Luckily, used engines can be found online for <$1K- if it comes to that.

 

Thanks for your response. I just want to clarify some things, I wrote this post in about 5-10 minutes and just wanted to get my point/story across. I also want to clarify that although it seems like I drove the car 15 miles knowing it had an issue, I had no idea until I had got home that day. Someone that had been there to take the car, gave me the story and I made sure that they spared no details. Had it been my choice I would have towed it to a very reputable vq shop near me, by this point I will most likely tow it to that shop.

Anyways I'm pretty sure the car is essentially done for, and I definitely think that I am not the one to blame. I really want to swap the motor anyways. But, thank you for your response and your advice.

 

Gotcha. Either way, the car should never have been driven with a compromised cooling system. It is just a ticking time bomb waiting to blow.

When you can, get the car to the VQ shop you mentioned and have them give it a thorough inspection. Who knows, it might be something simple. Worst case, swap a new engine in there and hit the road. You also mentioned the transmission was slipping, may as well have them look at that while they are in there- assuming the budget allows...

Good luck and please keep us updated.