I was hoping someone may have some ideas that can help me track down what is going on. I have a 2006 Elantra Limited 2.0L. When I first got it, it had a blown head gasket. Easy enough I replaced the gasket and replaced the head because it was warped. It ran for a few days but then had an electrical short from a hot wire that was lying loose in the trunk that I did not know about, and blew a whole bunch of sensors and relays. Now it just turns over but does not start. It has no codes either.

I pulled the fuel rail and the injectors are shooting fuel. I pulled the spark plugs out and they are sparking. I have checked the MAF sensor and it is good and measures within specs. I checked the TPS and it is good and measures within specs. I have pulled each individual fuse and looked at it and even checked continuity on them. I have tried jump starting it from another vehicle. I have tried cranking it on its own. Turns over and over just never starts...

These are the parts I have replaced so far. Some were replaced before the short and some after.
Neutral Safety Switch - replaced after short
Camshaft position sensor - replaced after short
Crankshaft position sensor - replaced after short
Ignition coil - replaced before and after short
Spark plugs - replaced before short
Spark plug wires - replaced before short
Fuel pump -replaced before short
Fuel filter - replaced before short
Fuel pump relay - replaced after short
ECU relay - replaced after short
Fuel injectors - replaced before short
Water pump - replaced before short
Knock sensor - replaced after short
Oil Control VVT Valve Variable Valve Timing Solenoid - replaced before short
Idle Speed Air Control Valve - replaced before short
Oil Temperature sensor - replaced before short

Any ideas or thoughts would be greatly appreciated. I am very stumped!!! I was thinking maybe another relay that could be bad and keeping it from starting but I have no other ideas what to check. Thanks in advance for any help!!!

 

Checked fuel injectors for pulse? Okay?
Checked for spark at plugs? Okay?

So does the engine have compression?
How does the engine sound while cranking engine (trying to start engine)?

Remove oil filler cap on valve cover
Shine a light at the valves and have a friend crank the engine
Is the valve moving?
Not moving then timing belt is gone
If moving then put back oil filler cap

Check for clogged exhaust?
Remove the upstream O2 sensor and try starting
If starts then clogged exhaust system
If not then put back O2 sensor

Did you try spraying a little starter fluid into in take? (avoid MAF if you have one)
Elantra usually has MAP and not MAF.
If it starts then fuel system issue
If it does not then put away starter fluid.

Only thing left is timing.
Leave to your imagination on how to test for that

 

I checked the fuel pulse and it was good. Checked each sparkplug and all 4 are firing. Timing is good, the engine was at TDC when I changed the head gasket. I did not check if the exhaust was clogged. I did find 2 more relays that are bad. One goes to the ECM and one Hyundai just has it labeled "power". The relays should be in Thursday. After I change them I will see if that gets it to work or not. If not I will check the exhaust. I also found out that Autozone can check the computer and powertrain control module. So that is also on the agenda to get looked at. I'll post on Thursday if the relays helped or not and also check the exhaust then also. This electric short has really wrecked havoc......

 

Fingers crossed.
Good luck

 

Timing belt not correctly installed

 

If the timing belt was not installed correctly,,,,,,,,,,,,,,,,,,,,,2.0 is an interference engine.
Best to start with a compression test and see what you get there.
If compression is not good, either get another head or have the replaced head repaired.
If,,,,,,,,,,,,,, that is found to be the problem, Make sure the belt installation procedure is followed to the letter.

Let's see what we find before going any further.

 

I agree... compression test...If it were only off by a tooth, it may not necessarily damage valves, b ut compression could be low... the backfiring at least identifies spark and fuel.... the only other reason (and requirement) for running is valve timing, and thereby compression... spark timing usually wont prevent start, UNLESS the plug wires are not correctly located. 1342 is firing order. In a waste spark design, 1 and 4 are on one coil pack and 2,3 on the other. Not certain if 06 is individual coil on plugs or not.

I'd be willing to bet either that individual managed to solve the problem and never post again, or the 13 year old car ended up in the scrap yard before Nov. last year

 

This thread is over six months old.
Either this person fixed this issue or sold the vehicle??

Since he never came back, it is easy to conclude that it was sold.
Making it someone else's problem.
But, reading this over again, he might have gotten the relays in and that fixed it??