Why wont accent start in cold
 

What would cause a 2003 Accent to not start under 22 degrees. It has 156,000 miles on it. 1.6L engine, manual trans. Just had the CPS changed two months ago. It will turn over just fine, but the engine will not ignite. If the temp warms up it is fine. If the engine has been running and is hot, it will start and run fine.

this is a common issue with the 1.6L, i have just gotten over it myself. there are several causes, but we will need more info from you first. these items should be tested for and eliminated as possible causes one by one. extra info may help narrow the list down.

firstly, by CPS are you referring to the crank position sensor or the cam position sensor?

if its the crank sensor, then we can rule that out. the crank sensors are known to cause this issue in this car.

next, we need to know if there are any error codes (check engine light) and what they are. those codes are what gave me the necessary info to properly diagnose mine. in my case it was a very inexpensive relay behind the dash on the driver's side, took me 10 mins to replace. its the main control relay that feeds several systems on startup, one of them being the computer.

being plugs or wires is unlikely as its not even trying to catch, just turn like an ass. i know the feeling all too well. however, the coilpacks could be having trouble not giving you spark. there are spark testers you can get really cheap, simple little tools you attach to the wire and they light up when the plug fires. if you're cranking and not getting spark, then you found the problem. honestly i once bought one for $3-4.

again unlikely, but fuel pump could be an issue.

a very possible issue is a bad wire somewhere....if thats the case i wish you luck, you will need it.

More info
 

The temperature in Nebraska creeped up to 28 degrees. The Accent fired up and I was able to move it to a garage. However, the temperature dropped again I was in the same boat later that night.

It didn't start easily, it choked a bit and finally started. The exhaust was rich.

I threw a code reader on it, but it said: There are no codes. 7 Of 7 rediness monitors are complete.

CPS refers to cam shaft position sensor.

hmmm not much to go on, diagnosing these is never fun.

i'm guessing that injectors are firing fine and you had some fuel pooled in there causing it to run rich for a bit. check the plugs and see if they are starting to get the soot on them, that would confirm the overfueling.

next, get some sort of spark indicator tool like i mentioned. its sounding like the coils aren't firing and this would be the time to confirm that.

next, you may have to replace the crank position sensor (CKP) as part of trial and error. you should be able to find the specs on www.hmaservice.com and test with multimeter. another test, grab a can of the 'dry and go' or whatever they call it. spray to dry out crappy failing distributor caps and the like. when it doesnt want to start, spray the CKP in that crap and see if it lets it start. if it does, you found the problem.

alternatively, you can do the reverse. get a spray bottle and mist/spray all around that sensor and see if you can make it fail to start. would also confirm a bad CKP. same with the coilpacks.

Hi there, I just found out that my mechanic gave me the wrong information. He originally replaced the crank shaft position sensor in october. I took a hair dryer on a cold day and warmed up the sensor. It didn't make a difference, still wouldn't start. Recently, we haven't had a cold enough day to make it not start.

What do you think the probability of it being the engine coolant temperature sensor?

Also, I did speak to a mechanic at Hyundai. He told me I should scan the ECM when its not starting to get a better picture of whats happening internally. Where do I get a scanner that can do that? I rented one from a local auto store, but I think it just scanned for stored codes. Where can I get one that will mind melt with the ECM and give me real time data?

some just do codes while others can show more data. i have one like that, they're not much more expensive....for example, mine cost me around $150 CAN while a cheap code only cost around $50. it was worth it, but you have to have some idea of what the numbers, etc mean.

CKP can be eliminated as an issue if it was replaced recently, also good call on the hairdryer idea. nothing wrong with doubling up on your testing!

engine coolant temp sensor is always a possibility, check www.hmaservice.com under the DTC's and find an engine diagnostic code for a failed one. it will give you instructions on how to test the sensor and its location. you just hook a multimeter up to it and check for resistance.

seeing as its a pretty cheap part, i would just outright replace that main control relay. it *can* cause your problems, it was the problem for me and its cheap. probably $10 to stroke that one off your list. its located behind the dash on the drivers side, under the steering wheel, on the wall near the door. again check www.hmaservice.com for pics and stuff, i think you can find it under the 'low system voltage' DTC.

and yes i'm too lazy to copy and paste all that, i figure you can handle that just fine:p

Finally decided to take the car into a mechanic to have a diagnostic run on it. The temp was about 16 degrees when they tried to start it. Fired up on the first try. They phoned me to tell there was nothing wrong. I picked up the car and 12 hours later it wouldn't start.

Spoke to Hyundai dealer yesterday. They told me to make sure I have cheap plugs installed. Nothing fancy like split fire. They also told me to use a higher octane fuel. If there was a sensor not working, it would throw a code (which it isn't). They finally told me to try starting it with the pedal halfway down, then fully down.

I bought an engine coolant temperature sensor, but I have no idea how to get the old one out. Its back behind the engine. I plan on testing the old one with a multimeter.

I asked Hyundai about that relay, but they didn't know what I was talking about.

ok for what you are going through, replace the main control relay!! i don't care if its one from a junkyard, it takes 5 minutes and could be the problem, i know it was for me!

this is for the 1.6L 2004 accent, so its an LC2. i could not find any info for the 2003 LC accent, so i'm hoping this is similar. its directly to the left of the steering wheel behind the dash. little black relay bolted to the left wall of the car, its a 5 pin connector. sorry pics aren't any better.

tell them to replace this relay as if you were troubleshooting for low system voltage error code. if they still don't understand, they are dumb. go somewhere else.

http://www.hmaservice.com/viewer/dis...lc15056211.jpg

now...plugs yes just use NGK plain coppers gapped properly. these engines are not designed for platinums and iridium is total overkill.

higher octane fuel? these engines are designed for the regular gas. try it if you want, it won't make any difference.

bad sensor would be throwing an error code? HA HA HA! these guys are geniuses. normally yes, but there are PLENTY of times in these and other cars that the ECU fails to throw the code. furthermore, many codes require the error to happen TWICE in TWO trips. before the engine light is illuminated. so you go once, no error code. next drive car works fine. third drive problem comes up, but ECU still won't report unless you hook up your code scanner and sometimes not even then. to make the matter even worse, these accent electronics can be flaky at times.

oh and take them a pic of that relay. its from info off www.hmaservice.com straight from hyundai.

I promise I will replace the main relay. I just have to go back to the dealer. Thanks for the pic. Guess what? I put NGK plugs in, and a half tank of the high octane fuel a couple of days ago. Temp dropped down to 12 farenheit tonight and it started. It still wasnt like it used to be, but at least there was some bite. Its going to get colder tonight, I will see if it starts tomorrow.

lol good luck with that. the relay may not fix it, only suggesting it because it *can* cause your problem and it was for me. that and its a very cheap/easy job to replace it. can be done in about 10 mins.

glad to hear that the new plugs and different fuel helped, as if the coils aren't putting out enough voltage...another possible problem that seems to happen with accents!

one thing i forgot, i did have some minor issues with missing in my accent while ago...i eventually came to the conclusion that the recommended plug gap is wrong. i gap mine about 0.005" tighter and it seems to make a world of difference for me. just a thought.

No spark No fuel
 

I've been having issues starting my 2003 Accent. I had a friend hook up a fancy scanner tonight. I now have more questions than answers. With the engine off, the engine load is 100%. The TPS wide open is 78, should be 98. While trying to start, there is no spark and the fuel pump relay is set to 'off'. So what would cause this to happen. It will turn over fine, but nothing happens. Oddly enough, when it gets warm, it will start fine. All temp sensors were reading the same as outside air. Its a 1.6 engine.

One of the most common causes of no fuel/no spark symptoms is a bad crankshaft position sensor.

Ok, one year after my original post I finally figured out the problem...... Crank shaft position sensor. Now before I hear the "I told you so's" I want to explain why I didn't think it was the crank sensor originally. I had just replaced it two months before with a brand new sensor. Also, I stuck a hair dryer on it with no avail. Apparently the sensor was sheepish about the cold. I hooked an ohm meter up to the old sensor and then threw it into the freezer. There was a difference in resistance, it was .87 warm, .72 cold.

The way I figured it out was to have a friend hook a $4000 scanner upto my car. It showed no signal from the crank. Thanks for everyone's help on this issue!

Just another thought, even though you have solved your trouble, a friend had the same issue, it turned out to be the Oxy sensor.

Hard Start in Cold Weather
 

I will get right to the point... the fix is to make sure the Crankshaft Position Sensor is pushed all the way into its mounting location (hole) in the block. Most often you will find that the rubber o-ring on the sensor prevents sensor from seating all the way into the block. Should the o-ring present a major problem in trying to seat the sensor, you can get another o-ring or delete it and use an RTV sealant (that can handle the engine temperature) instead. Once the Crankshaft Position Sensor is properly seated the cold start issue should cease.

Technical explanation: When said sensor is not seated properly, the gap between sensor and Reluctor Ring (on crankshaft) is is larger than it should be... this results in a weaker electrical signal to the sensor and; therefore, the signal to the computer that instructs the fuel injectors to operate will be too weak to initiate injector operation and the engine will not start.

Why only when cold? Signal strength from crank sensor is dependent upon two things: 1) the gap between sensor and reluctor ring and 2) how fast (rpm) the reluctor ring is turning. Cold weather causes available battery power to be weaker and motor oil to be thicker... result is lower crank speed (RPM).

This fix was found through weeks of research, a lot of trial and error, and quite an expense (new plugs, wires, coil pack, fuel sending unit, and fuel pressure regulator). Should you be looking for a code on your scanner (or Auto Zones scanner, or Pep Boys scanner....)... not going to happen as a trouble code will only appear if the sensor is bad (open coil); sensor is not bad, it is just not properly seated into the block.