Need experience tech help with my car not getting spark or fuel

[shorod]

On the relay, pins 85 and 86 are the coil. You should see probably 10's of ohms across those two terminals. Pin 30 is the common, and will connect to pin 87a when off (if a SPDT relay) and will connect to pin 87 when the relay coil is energized.

-Rod

[Jag1980]

Originally Posted by mike23462

Just curious did you ever check that ECM relay. You can do it with an Ohm meter. Those stupid things are kind of expensive new. I got mine from a junk yard for $4.08. The relay is easy to test. There is a schematic on the top of the relay. You should get a reading on your ohm meter showing 2 good paths through that relay and pin 30 should not be shorted to any of the other prongs. That is with the relay removed from the vehicle and no electricity applied.

I replaced the ECM with a Tested one from a junk yard and still have the same problem. So I didn't bother to do any further testing on the ECM

[merdoc]

you've prob tried most of this - i'm a ford tech with no hyundai experience.

1) fault could be 'ignition side'? - most ems's cut off pump if 'no spark' so check cam sensor & coil.

2) from wiring diag check particularly ems ground & power. also continuity of others if poss.

have you got any abd-1/2 codes? - can be a lifesaver but not always - you need a reader (cheap on amazon).

[shorod]

Originally Posted by Jag1980

I replaced the ECM with a Tested one from a junk yard and still have the same problem. So I didn't bother to do any further testing on the ECM

We're talking about the relay here, not the ECM. The relay is what provides power to the ECM. I remember you've checked voltages to the relay, but have you verified you have power to the appropriate ECM inputs and have the correct grounds?

-Rod

[Jag1980]

Originally Posted by merdoc

you've prob tried most of this - i'm a ford tech with no hyundai experience.

1) fault could be 'ignition side'? - most ems's cut off pump if 'no spark' so check cam sensor & coil.
I don't know how to read the wire diagrams so I don't know what wires to check.

2) from wiring diag check particularly ems ground & power. also continuity of others if poss.
What is the ems?

have you got any abd-1/2 codes? - can be a lifesaver but not always - you need a reader (cheap on amazon).
I never heard of what you just mentioned, so I'm not sure what you mean?
My neighbor came over with some $10k Snap On Scanner, So I'm not sure if that would have checked the codes you mentioned?

ooo

[Jag1980]

Originally Posted by shorod

We're talking about the relay here, not the ECM. The relay is what provides power to the ECM. I remember you've checked voltages to the relay, but have you verified you have power to the appropriate ECM inputs and have the correct grounds?

-Rod

I just bought one of these Computer safe LED test lights yesterday.
Now to test what you mentioned, I just need to unplug the main harness from the computer (ECM) and test the wires at the plug-in with the key on correct?

Is there a way to check a Crank sensor beside just replacing it?

[merdoc]

1) considering the fault, you really are at a great disadvantage if you can't read a w/diagram - perhaps your neighbour could help out?

2) sorry, ECM = ECU = ECM - i live in ireland.

3) you said initially that you replaced the ECM/ECU when your neighbour tested with a reader - he must have detected something(??).

you will find wiring schematics, ignition testing procedures etc & a wealth of other hyundai tech info here [inc DTC (dianostic trouble codes) codes detected by the reader].

this type of fault can ultimately damage your wallet by replacing uneccessary parts.
the relevant wiring diagram & a simple digital multimeter are nearly always your best friends.

[Jag1980]

Originally Posted by merdoc

1) considering the fault, you really are at a great disadvantage if you can't read a w/diagram - perhaps your neighbour could help out?

2) sorry, ECM = ECU = ECM - i live in ireland.

3) you said initially that you replaced the ECM/ECU when your neighbour tested with a reader - he must have detected something(??).

He didn't find anything with the code reader. With the symptom I was having with the car and from what we checked, he was about 80% sure it could be the ECU. We only looked at it for about 10 Min's together.

I hate asking him for help since he works on cars all day and I always ask for help with weird problems I always get. I try as much as I can on my own until I give up.. HA!

He going to help me more, but I have to get it into my garage becase it's pretty cold here. I need to clean my garage to fit a car and get some help pushing it into my sloped driveway.

you will find wiring schematics, ignition testing procedures etc & a wealth of other hyundai tech info here [inc DTC (dianostic trouble codes) codes detected by the reader].

I will check out what you mentioned.
That's where I have been getting my wiring diagrams from, but it's hard for me to understand perfectly because of all the different ways they split off and the multiple pages it continues onto.. knowing where it splits and to what it splits to. I look at it like uhhh...


this type of fault can ultimately damage your wallet by replacing uneccessary parts.
the relevant wiring diagram & a simple digital multimeter are nearly always your best friends.

I'm glad there is the Internet. I have saved 80% on parts cost from buying online. So it wasn't as bad as it could have been , haha..

I'm pretty good with other automotive repairs and I have replaced engines, 18+ hour job heater cores, timing belts, valve seal and lots of other things.. Wiring is something I haven't moved onto learning yet.
I'm slowly learning.

[shorod]

Originally Posted by Jag1980

I just bought one of these Computer safe LED test lights yesterday.
Now to test what you mentioned, I just need to unplug the main harness from the computer (ECM) and test the wires at the plug-in with the key on correct?

Is there a way to check a Crank sensor beside just replacing it?

Right, as far as testing for voltage and ground to the ECM, if you disconnect the ECM, you'll only be able to test inputs to the ECM that don't rely on a reference voltage from the ECM. You will be able to test ground and power, but I'd start by checking for voltages to the ECM relay first.

As for checking the Crankshaft Position (CKP) sensor, you might be able to test that with your computer safe (and presumably LED) test light. You could also use a very fast multimeter, but an oscilloscope would be ideal. You're looking for a low voltage AC signal when the engine is cranking. This would be rapid blinks on an LED test light if it will work for low voltages as well.

-Rod

[Jag1980]

Here's a interesting write up I found on someone else who is having the same issues as me. Different car, but the same problem and test done.
Very interesting toward the end.
http://www.aa1car.com/library/saturn04.htm

[Jag1980]

Originally Posted by shorod

As for checking the Crankshaft Position (CKP) sensor, you might be able to test that with your computer safe (and presumably LED) test light. You could also use a very fast multimeter, but an oscilloscope would be ideal. You're looking for a low voltage AC signal when the engine is cranking. This would be rapid blinks on an LED test light if it will work for low voltages as well.

-Rod

I used my LED test light on the tip of the sensor and nothing lights up.
Key on and trying to start the car, nothing..

So I removed the sensor.
There is 3 wires on the plug in.
I get 1 strong green light and the other 2 wires are very dim green light, which also indicates as being ground?

I tried this while key on and trying to start car.
Never got a red light..

Does this indicate a issue or just the wrong type of testing for this part?

I did not hook up my volt meter since I don't know where to touch the leads to..

[shorod]

What do you mean when you say you touched the test light to the "tip" of the sensor? Are you referring to the circle visible in the photo above? Or did you touch it to the terminals on the sensor? To test this sensor you'll really need to have it properly installed in the car and backprobe the signal wires. Obviously there is a belt that moves when the engine is cranking, so it's dangerous to backprobe at the sensor. You'll want to find a harness connector for the CKP sensor to backprobe at. The sensor is a hall effect sensor, it relies on a ferrous metal toothed ring on the crankshaft spinning past the pick up (sensor) with a small air gap. Each time a tooth passes by the sensor, a square pulse is generated, so when cranking the engine, a good sensor will generate a rapidly flashing light. The Camshaft Position Sensor works in a very similar fashion.

-Rod

[Jag1980]

FIXED !


It was the Crankshaft Positioning Sensor.

I found a wrecking yard and they had this sensor for $2.71

1 Bolt + $2.71 + 5 Min's of labor = Car Fixed
I forgot about this super cheap junk yard that has dirt cheap prices on all their parts.
I could have got a fuel pump from there for $7.00 and a computer for about $15

All this trouble shooting, parts bought and the headache was all just a little sensor.. haha....

Good learning experience.

Thank you you taking the time to help me trouble shoot possible causes of my car issues, it was very much appreciated.
Car started within 2 seconds of turning the key after sitting for 2 months with a new fuel pump, pretty good car.

The Fuel pump does not prime with the key in the on position, it only activates when the car is trying to start.

[shorod]

Good job, and thanks for the follow-up post. It's good to know that the fuel pump only works when the engine is cranking. I hadn't heard of that before.

-Rod

[mike23462]

Also Fixed!

Jag1980, shorod, and others,
Thanks for your help.
I had the same problem with a twist.

My ecm relay had gone bad at the same time. Replacing it did not fix my car so I kept looking for another problem. Everything I checked seemed to be ok until I checked the Crankshaft Position Sensor. I also went to a junk yard and purchased my sensor. It cost me $4.92 instead of about $90.00. As soon as I got home on Wednesday after getting the part I put it in and turned the car over and got nothing. However, I did notice that now after cranking the vehicle there was a new odor under the hood. Unburned fuel. I was in a hurry as the wife was on her way to pick me up. I didn't get to check the car again until Friday afternoon. It took me about 10 minutes to realize that some moron (me) while checking the coil primaries had left them unconnected. I re-connnected the coils and turned the vehicle over and found that my car had come back to life.

Thank you to everyone for responding to Jag1980. It really helped me to follow along and make sure I had already tried just about everything I could do. Without this board I probably would have scrapped a good car.
Thanks.

Oh and just like he said the pump only worked when the engine was turning over. I even put my hand on the pump to see if I could feel .