2004 Hyundai Sonata Questions

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I bought the car used in Dec and hadn't had any problems until recently. The thermostat started going from cold to the center line within a couple of minutes of turning the car on. this is everyday, even at night when the air is cooler. the other day when I was on the way home from driving my fiancé to work, I happened to look down at the dashboard and see that it was at the line just before reaching the "hot". As soon as I was out of traffic and able to move, the gauge dropped down. We went the next day and bought a thermostat, and that doesn't seem to be the problem. The man at the auto parts store suggested replacing the radiator cap, and we've done that. My fiancé doesn't know anything about working on cars and won't ask for help and is just guessing at what the problems are. We had the man at the auto parts store put the machine on the engine and it came back with a diagnosis for a catalytic converter, something that I'm not worried about at the moment. I'm trying to find out why my car is not sitting at a normal temperature, how much it will cost to fix it and is it possible the heads were cracked when I purchased the vehicle and how can I tell? The car is also losing power when you start off, which just started recently. Please I need some answers as I have upcoming surgery, not to mention, I'm the only one who drives this car and it's late at night when I drive this car to pick my fiancé up at work. I appreciate any help you can give me,

Thank You,

Barbara Goswick
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On Sunday the 16th, while driving on a highway, the car simply shut off. I was able to safely pull over, tried re-starting the vehicle, etc to no avail. My brother later towed it to his house where we began our research.

Things we noticed:
Fuses that we checked looked good.
Fuel pump turns on to prime the system when the key is turned on.
Cranking sounds normal
There's good compression (170 psi in the cylander we tested)
No spark

After some investigation online, we discovered that many people reported similar issues, and found that the crank position sensor was damaged from the balance belt teeth bending the "plate" that spins through the sensor. Since owning the car from 8k miles until 122k miles (so far) I've never replaced thet timing belt, etc. As such, we decided to replace the following:
timing belt
balance shaft belt
3 pulleys
hydraulic tensioner
crank sensor
crank sensor plate
water pump (while in there)
Cam position sensor (under warranty, easy to replace)

The timing belt was cracked and missing many teeth, so it was only a matter of time before there was a major problem! I guess I can be glad the car was disabled before there was valve damage!

The crank sensor installation was a little aggravating, since the platic clips (for the wire) busted while trying to push them into the hole. They were instead tie wrapped in place. The wire was pinched slightly while installing it, but we don't think there was any problem with this.

Likely unrelated to this story, there was also an exhaust leak. While I was ordering parts, I ordered the pipe that has the the second cadalytic converter and flex pipe. This was also replaced.

The timing belt was put on with my assistance to be sure the timing marks were lined up on each pulley. Once we believed it was lined up, we checked even further by manually rotating the engine from the crank and allowing the tensioner to tighten the timing belt. After 3 rotations of the crank, the cam sprockets once again lined up with the marks, and the other marks were spot on too. The battery was disconnected during the replacement of the parts, so we had to replace the connection before trying to start the vehicle.

After cranking the engine a few times and it didn't start, we began checking things again. We found:
Cranking sounded normal
No spark
Fuel pump did not prime while turning the key on

I then bought a code reader and tested it on my father and brother's truck - worked well. On my car, it displays "no link".

So... radio, headlights, cranking, etc all work fine. There's no fuel pump activity, no spark, and my code reader can't connect to the computer. The computer issue is new since the parts were replaced. We checked all fuses, and they seem fine. We also looked for the fuel pump relay, which was reported to be under the radio. After taking the console apart, I found NO relays there. However, behind the hood release cable, I found 4 relays in a panel. 2 black, 1 white and 1 blue. I think one of them is the fuel pump relay, but a search of part numbers didn't confirm this - they all came up as accessory relays.

At this point, I'm wondering if there's now a bigger problem, and if this is a dealer-only fix. Either way, we really needed to replace the timing belt, it was overdue. I'm open to suggestions.
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I have to replace Air Compressor on my Hyundai sonata car. Since my car is 10 years old, my Car shop is advising me to replace the entire air-conditioning system (including hoses, ect . that are fine)..which will highly increase the total repair amount. I am planning to keep my car for next 5 years…would you recommend to replace the entire a/c system or should I just replace the broken compressor only?
Thank you for your help.
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P0320 was code. Tach reads 0. Occasionally during a trip it'll read correctly but then drop back down to 0. Scanner shows engine running well. Any suggestions?
Diagnostic rest showed no problem. It does this randomly. The alternator, starter and battery have all been checked and are working properly.
I see that you subjected to change the crankshaft senor. However now the shop are telling me that my heads are bent and He doesn't think my motor will hold new heads because it has 179,000 and to get a new motor? Is that correct from a timming belt break
My car wont start at all. i was towing my car at no more than 30mph its a 2004 Hyundai Sonata 4cyl 5spd transmission. as i was hauling my car i hear a "boom" like if some on hit me. i kept on hauling the car cuz i saw nothing wrong. when i bring it to my garage my car wont start or run. i checked the fuel pump but there is no pressure and when i disconnected it no fuel poured out. don't know about cars so any help is appreciated. THANKS
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starting coil is changed. car is not starting. Some error is shown on they r saying chage the starter isf still dosent satrt hage electronic system of car. is it correct?
The battery light came on and the radio went off and the lights dimmed. What could be wrong?
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