Hi there!

I have a 1995 Sonata, which have been running smoothly up until recently. A month ago or so, it started to"choke" a little while running soI had to give it some more fuel to prevent it from dying when running. So I managed to keep it goin and after choking a little bit, it ran well again. Then I stopped to purchase some groceries or whatever, and when I came back to the car I couldnt start it. Wasnt even a small sign of willingness to crank.But after waiting for it to cool down i guess, approx 15-30 mins, it started somewhat reluctantly. So I drove it home and parked it. Next day it starts perfectly, and then the same routine... day after day. So I took it to the dealer, and he said it was a sensor that measured the temperature of the air coming in. He said he searched it for fawlty connections, and told me he had fixedsaid connectionso thatI perhaps didnt have to change the sensor, which he told me cost about 700 USD (I guess its the mass air flow sensor. Noticed they had it for 286 USD at autozone, but everything is more expensive in Norway :-/ ). So after I got it back from the dealer, during my very first trip, same old story. Nothing changed. SoIm quite reluctant to take it back to the dealer yet again as the first visit cost me approx 750 USD.(I paid 3000 USD for it, and im a student so I cant afford too much + I wont pay 1500 USD in repairs on a 3K car...)

SoI have a couple of questions about this issue;

1: Anyone had similarproblems? And if so what was the problem? (I readin another thread someone experiencingsomewhat similar issues, but then it was the crankshaft sensor)
2: CanI be certain the problem lies with the sensor he is talking about, which I assume is the mass air flow sensor (?)
3: When searching for used parts in Norway, theres a community for companies selling used car parts with a combined and easy to use internet catalog. (Ill probably get a used mass air flow sensor for ca. 50 bucks) In this cataloghowever Ican find both, directly translated, a: Air amount sensor, and b: Air mass sensor. So my question here is; are there really 2 different sensors that have seperate tasks of this nature or have they just cataloged it under 2 differentnames?Sounds pretty similar, amount/mass... (Might be hard foryou guys to answer thislol)

Sorry for the way to long post, but I really appreciate all answers that might help.

Regards
Tom

 

Do you actually mean the starter will not crank the engine over, or that the engine will crank over but not start?

 

The problem is it's a 1995, and it's in Norway, so it's the EODB II standard, which didn't start until I think 2001. So you can't just do a trouble code scan too easily, as far as I know. Anyway, the other problem is A LOT of things could cause the problems you describe. Most likely it's either the crank sensor or the camshaft sensor, as they fail the most. It could be the MAF sensor, but it's less likely. Another possiblility is a fuel pressure problem. And your mechanic is no help either, as he diagnosed the problem incorrectly. Oxygen sensor failure could cause this too. Did you pull out a spark plug and see if you get a blue spark when you crank it? How about do a fuel pressure check? Indeed, possibilities are endless here.

Sorry I'm not much help. Did you check ebay to see if you can get parts shipped to Norway? You can get used parts there if they will ship them to you.

 

There is a way to get trouble codes, I just can't find out how. Apparently it's a flashing code thing.

 

The starter cranks it, but it wont start, no willingness to fire i guess is the right way to say it.

 

So the MAF also checks the temperature of the air? Just making sureits the right sensor.If so im probably just gonna buy thisused in Norway for cheap, and if this isnt the problem i guessI can complain about therepairs done and get a discount or whatever if its the crankshaftsensor, and I need them toreplace this. Its quite weird if it has anything to do with the sparkI think, because as I said it starts perfectly when cold and runs a good 4-5 mins without problems at first. So shouldnt this problem be evident from the very beginning? But i guess maybe all problems should be present from the start lol. Thanks.

 

I don't think this is a problem with the MAF or the air intake temperature sensor. If either was the problem, the car would idle poorly and get poor mileage, but it would still start. I think you have a failing crankshaft position sensor. When these start to fail, they do exhibit temperature sensativity (cut out when hot). Next time it fails to start, crank the engine for 30 seconds or so and then check the exhaust for the smell of raw gasoline. Also, check for spark at one of the plugs. If no gasoline is present (which means the injectors are not firing) and there is no spark, usually confirms a problem with the crankshaft sensor. I would have that looked at (by a differnent mechanic) before spending money on a new or used MAF.

On most Hyundais, the air intake temp sensor is built into the MAF sensor body. When you replace the MAF, you are replacing both sensors.

 

Ok, thanks, Ill get back in a couple of days to let you know what happened. I just gotta dig out my car from the snow first :-)

BTW, at the dealer they did scan it, and he said, as itold u guysearlier that it came out as a problem with the airintake temperature sensor.But why does the computer miss with this?Your last post made more sense though than my mechanic, but shouldnt Hyundai`s ownprogrammes work? And the last time I had a problem I used anindependent mechanic, which i was very pleased with, and reasonable cheap (I dont think you will find a mechanic in this country charging less than 110 USD p/h :-/ ).And at first i contacted this very mechanic/garageand told them what the problem was, and they forwarded me to the Hyundai mechanics as they didnt want anything to do with this problem as theysaid itsounded like a Hyundai issue. So shouldI just ask this mechanic to replace the crankshaft sensor for me without scanning the system? Is this the safest bet?

Ill do the checkyou told me first though, andI really appreciateall the advice.

 

On U.S. based models, intermittent problems like a failing crankshaft position senor can take some time before an error code is generated. Without a stored error code, the scantool will not find a problem. I've been told it has something to do with the problem occurring during so many consecutive "driving cycles". If the car is driven for several short trips without incident, it appears to the ECM that nothing is wrong. Yes, you may also have a problem with the air intake temp sensor, but I still don't think that issue would keep the car from starting.

Carry a spare spark plug with you in the car. When checking for spark, I find it easier to watch or listen for spark by simply plugging the spare plug into one of the wires when cranking the engine by myself. Remember to lay the metal body of the plug against the block or some other grounded metal.

 

The following are troubleshooting hints for the crankshaft position sensor on a U.S. 1995 Sonata. Item #2 caught my eye and makes sense. Next time the car dies, watch the tachometer needle while cranking the engine.

Troubleshooting Hints

1. If unexpected shocks are felt during driving or the engine stalls suddenly, shake the crankshaft position sensor harness. If this causes the engine to stall, check for poor contact of the sensor connector.[/align]

2. If the tachometer reads 0 rpm when the engine is cranked, check for faulty crank angle sensor, broken timing belt, or ignition system problems.[/align]

3. If the engine can be run at idle even if the crank angle sensor reading is out of specification, check the following:[/align]
a. Faulty engine coolant temperature sensor[/align]
b. Faulty idle speed control motor[/align]
c. Poorly adjusted reference idle speed[/align]