After weeks of troubleshooting, replacing parts, car still wont turn over

[Liebshun]

At first glance I know this seems like a repetitive forum post, but hear me out. My husband and I just bought a 1997 eclipse 2.0 DOHC non turbo. Everything is stock on this car except for the aftermarket muffler on it. The car pretty much needed a whole new coolant system. Replaced thermostat, thermostat housing, radiator, water pump, timing belt, alternator, spark plugs, plug wires, battery, and a brand new head gasket. All within a week. After that it drove for about 2 weeks, then my husband heard a loud POP while driving the car. It coasted, and stalled. Hasn't started up since. Im not very versed on electrical problems, my experience lies strictly in the mechanical workings of cars. Now on our adventure, we've looked at every guide, thread, forum, topic and any piece of online information regarding this issue.
Here's the breakdown of what we've found out so far. First, we were getting fuel, but no spark. Traced the problem to the ECU. Replaced it. Still no start. Replaced camshaft and crankshaft sensors, still no start. The parts aren't faulty, already replaced the replacements. Had a licensed mechanic come out, and he's baffled. Says fuses and relays look fine (he checked them with a voltage meter), says he thinks there is a bad ground somewhere. Traced everything we could in the engine, no bad wires, no exposed wires, no bad grounds. At this point my husband wants to take a match to the car and be done with it. Right now Im trying to get all the main relays replaced just to cover bases. Do you guys have any other clues?? Thanks in advance.

*Edit* - We also have perfect fuel pressure, sitting at around 55 psi. You can hear the fuel pump engage when the key is switched to the ON position.

 

[92AWDHX40]

http://www.dsmtuners.com/forums/articles-miscellaneous/217951-how-diagnose-no-start.html

 

[Dave4g63]

Have you checked the timing belt and the compression?

 

[Liebshun]

http://www.dsmtuners.com/forums/articles-miscellaneous/217951-how-diagnose-no-start.html

Ive already checked that guide.

Have you checked the timing belt and the compression?

Timing belt is brand new and was timed correctly. Compression is fine.

 

[Dave4g63]

is the pcm throwing any codes?

 

[Liebshun]

is the pcm throwing any codes?

It wasn't for a while, then after we changed the ECU, we finally got ONE code. It was for the camshaft sensor. Thats when we replaced it and the crankshaft sensor just to be safe. Now there are no codes at all.

 

[Dave4g63]

Your problem is not getting spark right? Have you checked the coil and the wiring to the coil?

 

[Liebshun]

Your problem is not getting spark right? Have you checked the coil and the wiring to the coil?

I had a mechanic check all of that for me, because I dont know much about these things, and he said that there was power, but it seemed to be an issue of grounding. The plugs and wires are all brand new, and I was told that the coil pack was fine. The same mechanic told me that he had no idea what was going on, and that I should take it to an automotive electrician to have it looked at.

Im about to head outside and check the plugs for spark again. I haven't tested it since replacing several parts. Will come back with results.

Just did a plug test, and no spark getting to them. Maybe the MFI/ASD relay is bad?

Anybody else have any ideas? Thanks

 

[Rock2610d]

I am not too versed with non-turbo cars but I would get a meter out and check the ignition transistor, and coils, if non-turbos have them.

Here is a link to test the transistors. AKA Ignition module THANKS TO luv2rallye
http://www.dsmtuners.com/forums/articles-electrical-wiring/229419-how-test-power-transistors.html Never mind on edit....2g nt do not have these sorry.

And here is one for the coils.
http://www.dsmtuners.com/forums/newbie-forum/385420-bad-coil.html

Make sure the ground from battery to engine is good. A loud pop sound could have been a transistor AKA Ignition module blowing.

2g N/T 4G63: 47-50 psi You have tested yours at 55....a little high.



Hope this helps.

 

[Liebshun]

I am not too versed with non-turbo cars but I would get a meter out and check the ignition transistor, and coils, if non-turbos have them.

Here is a link to test the transistors. AKA Ignition module THANKS TO luv2rallye
http://www.dsmtuners.com/forums/articles-electrical-wiring/229419-how-test-power-transistors.html Never mind on edit....2g nt do not have these sorry.

And here is one for the coils.
http://www.dsmtuners.com/forums/newbie-forum/385420-bad-coil.html

Make sure the ground from battery to engine is good. A loud pop sound could have been a transistor AKA Ignition module blowing.

Hope this helps.

Hey, thanks! I never thought about checking the ignition module. I've been thinking really hard about that POP that my husband heard and I just couldn't wrap my mind around what it could be.
I'll check everything you suggested and post the results. Thank you.

 

[Mischif]

Unplug the ecu and then turn the key to on. Test pin 44 on the engine harness. It should be at 8 volts. If its at anything else, like .4volts or something then that wire is shorting out. It feeds power to the cam, crank, and vehicle speed sensor. Unplug these three sensors one at a time while testing the wire. If it changes after unplugging one then you know you have a bad sensor. If no change then it more than likely is shorting out underneath the intake manifold.

Also test the center wire on the coil pack. With the key in the on position it should read 12 volts. If it doesn't then as long as pin 44 is reading correctly then your issue would be in the asd relay.

Also the pop could of been unburnt fuel in the exhuast igniting, due to no spark.

 

[pbmaxx74]

2g N/T 4G63: 47-50 psi You have tested yours at 55....a little high.

I know I'm no expert, but doesn't a 2g n/t have the 420a engine?

 

[Zufelt]

I know I'm no expert, but doesn't a 2g n/t have the 420a engine?

Yes.