Got a problem and need some input...[no-start condition]

[Abomb4eva]

alright pretty much my car won't start right now. I got new spark plugs and they work, the battery is also fine. Just curious if anyone would have any ideas on what the problem could be. Thanks.

 

[GTM]

Originally posted by Abomb4eva
alright pretty much my car won't start right now. I got new spark plugs and they work, the battery is also fine. Just curious if anyone would have any ideas on what the problem could be. Thanks.

You need 3 things for an engine to run, fuel, spark, and valve timing. Have you checked that these are present?

Cheers,
GTM

 

[turbolover2]

edit: GTM: You beat me to it by only a few minutes, I was typing while you were posting. And yes, you're right, valve timing must be pretty close (prefferably dead on, but it will run if it's close).

You have to start with the basics. First thing to do is check for spark and for fuel. To check for spark, pull off a plug wire and insert a screwdriver into it (preferably with an insulated handle, the shock won't kill you , but it will suprise you). Hold the screwdriver shaft near (about 1/8 to 1/4 inch away) a piece of grounded metal on the car (the bracket with the hole in it on the right side of the exhuast manifold is good spot). Have someone crank the car and watch the screwdriver. If a spark jumps from the shaft to the metal then you know you have spark. You can also buy a spark tester (it looks like spark plug, should be available at any auto store) that way you can do it yourself. If it doesn't have spark, work backwards, check all the ignition cables (spark plug wires), check the coils, etc. (a manual would help you out a lot with these things, Haynes or Chiltons are easy to come by).

If it has spark you need to check for fuel pressure. Easiest way to do that is to take the return line off the fuel rail. That's the rubber line at the drivers side end of the rail (not the vacuum line from the regulator though). It has a small metal squeeze clamp holding it on. Remove that hose (be careful and don't hold your face close, fuel may spray out a little, and trust me, it doesn't taste good and your eyes won't appreciate it). Then turn the key to the "ON" position, or just crank it. If fuel starts pouring out you know you have fuel pressure. But be quick about it and shut it off ASAP so you don't spill too much gas. If you have no fuel pressure you'll need to check for power at the pump while cranking (the manual will help).

If you have fuel pressure, the next step is to check for injector pulse. This is hard to do without what are called Noid lights (they plug into the injector harness and blink each time the injector would fire). You could try using a multimeter and check for 12 volts while someone cranks the car, but that usually doesn't work, the pulse is to quick to be picked up by a meter.

Start with the basics though, it usually ends up being a simple problem like a fuel pump or a bad ECU. One more quick thing to check, turn the key to the "ON" posistion. If the check engine light stays on solid for more than about 10-15 seconds that's a sign of a bad ECU which is very common on older DSMs. Here's link from VFAQ.com that can help with that problem: http://www.tmo.com/howto/ecu1g/caps.html

But don't try to replace the caps yourself unless you are an expert at soldering, the ECU can be damaged if done incorrectly.

And, as GTM stated, valve timing must be correct. Again, the manual will help or this link from VFAQ.com: http://www.vfaq.com/mods/timingbelt-1G.html

Good luck.

 

[Abomb4eva]

thanks a lot guys, i will check all that soon...

 

[GTM]

Originally posted by turbolover2
edit: GTM: You beat me to it by only a few minutes, I was typing while you were posting. And yes, you're right, valve timing must be pretty close (prefferably dead on, but it will run if it's close).
...
Good luck.

That's because MINE was shorter.

There was so little to go on I wasn't going to explain the basic physics of the internal combustion engine. So many posts that get made and the member never returns to even read them of give a follow up. Sometimes I think to have a prepared post #23, or post #1, my tire is only flat on the bottom why won't it roll.

Cheers,
GTM

 

[Doug99RS]

Are there any fault codes in the computer?
Doug

 

[Abomb4eva]

the spark plugs spark and fuel comes out of the rail and I can hear the fuel injectors make a clicking sound, and the car still won't start. It had been running a week ago or so, but since it has gotten real cold it won't start at all now.

 

[GTM]

Originally posted by Abomb4eva
the spark plugs spark and fuel comes out of the rail and I can hear the fuel injectors make a clicking sound, and the car still won't start. It had been running a week ago or so, but since it has gotten real cold it won't start at all now.

Sorry, that doesn't help much. Do you have a check engine light flashing a code?

Have you checked the compression and the valve timing? Have you mixed up the spark plug wires? What plugs did you install, what gap did you set?

Have you tried starting fluid?

Cheers,
GTM

 

[turbolover2]

I suggest pulling out the ECU (very easy, three 10mm bolts under center console). Make sure the battery is disconnected. Take out the screws on the ECU case and take the case apart. Look for the capacitors (little battery shaped things clustered together). You'll probably see that they have leaked (it will look wet around them). You can even take the circuit board off the back of the ECU case (4 phillips screws) and flip it over. In some cases the leaking has caused a short and burned through the circuit board. Refer to link in my previous post so you can see what I mean.

9 times out of 10 (on a DSM), if you have spark and fuel (and the car was recently running fine) the ECU is no good due to leaking caps.

And be sure to pull the top timing cover off and check the valve timing like GTM said, it's not uncommon for an old belt to slip or even break altogether. That's how it happens, one minute it's running great, and then snap, the belt breaks and there goes the neighborhood.

If all the above things are okay, next thing is a compression check, which can also be found on www.vfaq.com

Good luck, keep us posted.

 

[Abomb4eva]

alright i'll try that next, it sucks cuz i am at college now so i may have to wait a few weeks but i'll see. Thanks again guys.

 

[GTM]

Originally posted by Abomb4eva
alright i'll try that next, it sucks cuz i am at college now so i may have to wait a few weeks but i'll see. Thanks again guys.

Understood. If there is any part of what has been suggested that you are not comfortable with then discuss it. At the time of the problem(s) did you notice the smell of some electrical device burning?

As turbolover2 mentioned it could be the ECU which you don't want to replace unless needed for they are quite expensive. With that as a possibility you should start looking for a good used unit or rebuilt for they ain't cheap at prices ranging from $250-$400. If the cranking is uneven then checking that the cams are turning could be a first step, this can be done just by looking through the oil fill cap while someone cranks long enough to see the cam move. If it doesn't then you direct attention to examining the timing belt, if it does and the seat of pants compression was good then pull the radio so you can get access to the CPU.

Cheers,
GTM

 

[Abomb4eva]

the cranking is even and i don't remember any weird smells. I had my dad look at it when it warmed up a little back home. He said the car almost started, which is what used to happen when it was warmer. Then the cold weather set in, and the car wouldn't get close to starting.

 

[GTM]

Originally posted by Abomb4eva
[B...
which is what used to happen when it was warmer. Then the cold weather set in, and the car wouldn't get close to starting. [/B]

That could be a symptom of a temp sensor failing which makes sense. Under the thermostat in the housing are the temp sender for the gage and the temp sensor for the ECU. Add that to the list of things to check, the manual will give the testing process.

Cheers,
GTM

 

[turbolover2]

GTM, a bad temp. sensor wouldn't cause a no-start on a DSM. You might not even get a CEL from that (it's seems, sometimes, to have almost no obvious effects). If the one for the gauge is no good, the gauge simply won't work. If the one for the ECU is no good, the ECU won't get the proper info and may cause the car to run rich, but, other than that, it really doesn't cause any problems (at least in my experience. On my personal car, the wire for the ECU temp. sensor broke and I didn't even know it until I just noticed it by accident one day). If it's almost starting, I'd be willing to bet it's a bad ECU (as long as the t-belt is okay. I've had cases where the belt is broke but I could have sworn that the motor sounded like it had good compression. It can be tricky somtimes to diagnose compression by ear or feel).

And an easier way to get to the ECU is to pull off both side panels on the center console (there are some 10mm bolts hidden behind plastic clips). You won't be able to reach the bolts if you pull out the radio.

Good luck.

 

[turbolover2]

Also...

If the ECU is bad it will sometimes cause the injectors to stick open, dumping fuel into the cylinders. This effectivley kills any seal the rings had or have with the cylinder walls, and therefore will lower your compression a considerable amount, leading you to believe that you have an internal problem when you really don't (sometimes).

If you do a compression check before you look at the ECU keep an eye out for fuel spraying out the spark plug holes while cranking. This is a good sign that the injectors are dumping large amounts of fuel when they aren't supposed to.

Good luck and don't worry, you'll figure it out eventually.

 

[Abomb4eva]

haha i hope i do soon. i'll keep you all posted when i find out some more results. thanks again.

 

[GTM]

Originally posted by turbolover2
GTM, a bad temp. sensor wouldn't cause a no-start on a DSM.
...
You won't be able to reach the bolts if you pull out the radio.

That wasn't the experience I had on my son's car. After the valve job he didn't plug it in and it tried to start and then failed. Plugged it in and same problem, found it was out of spec, replaced and car started.
...........................

Was at DIY yard 2 weeks ago and of the 13 cars (Laser, Talon, Eclipse) at least 3 had the ECU removed through the radio opening. Some harness connectors were loose, others were attached to a bracket/brace.
................................

Abomb should figure out a diagnosis plan which makes the most sense for his conditions. The fewer parts he has to touch, remove, and inspect the better off he will be.

Those parts like the ECU which require outside diagnosis if he doesn't see or smell anything abnormal then either have to be taken to a service for advanced diagnosis or reinstalled. Whereas, checking for cam rotation requires no tools, nothing has been disabeled which will prevent subsequent diagnosis.

Diagnosis is an art, it doesn't always work going to what you _MAY_ think is the problem but to eliminate what you think it is NOT. Once comitted into the ECU he is railroaded to see it to the end conclusion which then disables the car for anything other than cranking with a remote starter button. No related relays or sensors can be tested while the ECU is out thus he's effectively stuck until he sees this to completion which may require him to mail it to a service and wait for a return. It's one thing to be under the umbrella of a well equipped shop where all the diagnostic equipment exists, you run to the parts department and borrow a good unit and plug it in. When you are stuck along side the road you don't have all these tools so a different plan has to be implemented which best fits the conditions.

Cheers,
GTM

 

[turbolover2]

Originally posted by GTM
That wasn't the experience I had on my son's car. After the valve job he didn't plug it in and it tried to start and then failed. Plugged it in and same problem, found it was out of spec, replaced and car started.

Well, that's why I said "in my experience". But I just don't see how that can be. I'm going to unplug my temp. sensor and see what happens, I'll let you know. If you're right I won't say anything.
...........................

Was at DIY yard 2 weeks ago and of the 13 cars (Laser, Talon, Eclipse) at least 3 had the ECU removed through the radio opening. Some harness connectors were loose, others were attached to a bracket/brace.

I guess you could take it out that way. To be honest with you I've never tried. It seems easier to just take off the side panels and not have to deal with disconnecting the radio.
................................

Abomb should figure out a diagnosis plan which makes the most sense for his conditions. The fewer parts he has to touch, remove, and inspect the better off he will be.

That is 100% true. It just seems to me that all signs point towards an ECU problem (as long as the timing belt is okay).

 

[turbolover2]

Well, GTM, I stand corrected. You were right, the temp. sensor being unplugged (or just plain broken) will cause a no start (I just tried that very scenario). I'm so ashamed at my lack of knowledge.

Oh well, sorry to have confused the situation.

 

[GTM]

Originally posted by turbolover2
Well, that's why I said "in my experience". But I just don't see how that can be. I'm going to unplug my temp. sensor and see what happens, I'll let you know. If you're right I won't say anything.
...

Here's the sticky part of that test for which I don't have an absolute certain answer so it's only suspicion. An unplugged temp sensor will be recognized as an open circuit and a default value will be taken by the ECU. (Limp home mode??) However, a sensor which thinks it's -40 degrees (hypothetical number) is a real number wich the ECU will use as valid input. When I tested my son's unit it was only 200 ohms out of spec so not a complete fail but kept the car from starting as the plugs were now wet from the previous attempts.

The fact that Abomb~ car was running, the weather got colder and then deteriorated over a few days. This suggested it wasn't the ECU from all the reports I've read here for they just die in one catastrophic failure and no shades of gray. The process sequence I suggested costs him no money, (always a concern with DIY) only diagnostic time, and as mentioned before if he finds nothing with the ECU he's now on the horns of a dilmma, does he plug it back in or send it out for more advanced testing which now imobilizes the car. I'll be redundant, sometimes it's better to find out what it's _not_ rather than plunging into a path which _ALSO_ may prove to not be the failure. My suggetions are based on 40 years as a professional in the industry and some 20k-30k cars I've worked on when I twisted wrenches. He could ask his father to crank and see if the cams move which would help Abomb~ narrow down how he will approach what remains to be diagnoased.

Cheers,
GTM

 

[GTM]

Originally posted by turbolover2
Well, GTM, I stand corrected. You were right, the temp. sensor being unplugged (or just plain broken) will cause a no start (I just tried that very scenario). I'm so ashamed at my lack of knowledge.

Oh well, sorry to have confused the situation.

Not to be ashamed, your points (ECU) are valid and warranted consideration and still can be the source of the problem.

BTW there is yet another item not considered and that's the air intake sensor. As we know sometimes you get a couple of iffy parts starting to fail, the sum results in a no start yet you replace 1 and it still doesn't run right.

I've seen a lot and I mean a lot of ECUs get replaced because of poor diagnosis, some at customet's expense but mostly under warranty. As service manager you have to review all warranty claims prior to submission, when you see an ECU charged out and a temp sensor on the same claim you become suspicious the mechanic really didn't do a proper diagnosis and was just covering his arse with the shotgun approach. (shotgun approach is throw enough parts in there and you are bound to fix the problem) The factory was pretty good about it and would pay the claims but on occasion would come a warning about a particular mechanic's skill level. This happens in independent shops a lot more frequent for they don't have the training or equipment so the customer ends up with a $$$$ bill and a bunch of excuses to the customer.

Cheers,
GTM

 

[Tried2Live]

I seem to be having the same problem. I pulled out my ECU and it looks BRAND new inside and out, so I'm questioning the coolant temp sensor. I was going to check it, but which one is it?? Top, Bottom Left, or Bottom Right?? (When standing at the front of the car looking.)

 

[GTM]

Originally posted by Tried2Live
I seem to be having the same problem. I pulled out my ECU and it looks BRAND new inside and out, so I'm questioning the coolant temp sensor.
...

It's the unit with 2 or more wires, the single is the temp sender for your gage.

Cheers,
GTM

 

[Tried2Live]

Well it wasn't the temp sensor... I replaced that and it didn't change a thing. (I should have just checked it first, but oh well.) There's fuel, but no spark. Is there a fuse for the coils, or do they regularly go out or anything? What else could it be? Just the ECU?

 

[GTM]

Originally posted by Tried2Live
Well it wasn't the temp sensor... I replaced that and it didn't change a thing.
...

There are a couple lessons here: reading similar complaints and thinking they are the same and the same conclusions can be derived. The other is _NOT_ testing before spending $38 and establishing it was a failed unit.
..............

I took a quick look in the manual and didn't find the circuit for the spark coils so can't answer if they are fused. If you don't have a manual it's a must especially when trying to diagnose problems.

Cheers,
GTM