still no spark? Please Help

[mikes94q]

1994 Q 60k miles, had bent rod. Replaced rod and now will not start. I have checked the grounds and wiring, but just get no spark.

I did notice when I was trying to start it that the starter is not spinning it very fast. I have the battery and jumper cables hooked to my suburban and made sure that it has ample power.

Everything else works, windows, locks, sunroof, etc.

I did notice that one of the cables that goes from the fuse box to the right front wheel was torn from the connector. but I don't think it has anything to do with the ignition system.

It is getting gas, just no spark. Tried also testing the ignition control mods but not sure that they would both go out at the same time.

PLEASE HELP. I need to get my car running. My other car sold a lot faster than I expected and now down to one between the wife and I.

ANY ADVISE WILL BE WELL RECEIVED. Thanks.

[Infinitiguy19]

Try soldering the split wire together...

Why do you make so many new posts instead of bumping up the old ones?

Is there a Infinti trained Tech (Since 1989) near you?

[mikes94q]

I have not found a tech that I trust. I worked at a dealership for several years and still have little faith. Sorry about the new posts.

[mikes94q]

still trying to figure out if my problem is the ignition control modules. Does anyone know if I am using a ohm/volt meter what reading I Should get to the connection from the ignition control module, along with what reading I should get from the harness that connects to the module.

Thanks

[Q45tech]

Use oscilloscope to view the switching [dwell] pulse from ecu to ignitor as you crank.........make sure transistor is getting base signal before begining to test robust ignitor assembly [just 4 transistors which act as 4 sets of points].

Obvious the coils must have +12 volts continuously during cranking and running.

[mikes94q]

Yeah I dont have a oscilloscope. I have a decent multimeter. Is there a way that I can check to ensure that the right amount of power is getting to the ignition control modules. I just need to narrow down the problem. I do get a small signal from the wire harness that plugs into the modules just now sure if I'm getting enough. So, I was hopping that someone would know what the specs are.

Thanks

[djwarner]

I've been watching your plight since before you diagnosed the piston rod. I feel for you but don't have anything specific to contribute at this time other than this....

Assuming the engine had spark before you tore it down, I can't help but think you left something disconnected. How about the ground strap from the engine to the frame?

May I suggest you walk your way through the repair again, step by step, rather than the re-assembly. Say each step aloud as if you were explaining it to someone who wasn't there the first time.

The odds of you having a random failure at this exact point is very slim. This leaves something disconnected or something blow because of a short as the prime suspects.

[goody90q45]

Since you mentioned weak cranking in your first post I've been wondering all along if the engine is just flooded from trying to start with a jumpered battery. Just for the heck of it try holding the gas pedal to the floor and cranking the starter for 30 seconds or so. Do you have a strong battery or are you still jump starting?

[mikes94q]

I'm running jumper cables to it from my suburban (it has two batteries) just to ensure I maintain power and not kill a good battery. I have tried to do it with the gas pedal down to the floor but not for 30 sec, maybe like 5-10 sec at most. I'll try again. The main concern is even when I have a spark plug pulled out and ground it to the car I have yet to get a spark from it. I remember reading that these cars a pretty specific to the type of spark plug but wasnt sure what was recommended.

***I also feel that maybe I shorted the ignition control modules but not sure if I'm testing them right. I went per the fsm but got failed results. Would hate to purchase new ones if they are not the problem, pretty pricey parts***

[Infinitiguy19]

This ignition modules are a dime a dozen, There are some people paring out 1994-1996 Infiniti Q45's might want to see if they still have power transistors.

But if the spark plugs are all good then we can assume the coil packs are all good (There is a test in the service manual to be sure (Resistance test)).

I have a spare 1994 Q45 ECU I can lend you if you think thats the problem. If you cover the shipping I will send it to you to try out. It is a 1994 Infiniti Q45 ECU with TCS and California edition. TCS and Cali doesn't matter in the least as you want to see if the ECU is the problem.

Try what Mike said first and see what happens after 30 seconds.

[mikes94q]

After 30 seconds it def had more cranking power but still no spark. was also checking the camshaft position sensor, it seems to be operating correctly. I have the newer version of the ignition control module found more on 95 and up. Yeah the earlier versions seem to be very inexpensive in comparison.

[Infinitiguy19]

Did you check the compression just to be sure?

[mikes94q]

not yet. if i cant get it running this week I'm going to have a tech come out the following week. I had a compression tester but it broke.

[Q45tech]

Explain in detail how you replaced bent rod, especially the head removal and replacement and retiming the engine?

[mikes94q]

Basically just followed the FSM step by step. I did remove both heads following the removal instructions to make sure that I didn't warp anything. During installation especially with the timing chains I triple checked everything to ensure that I lined up the timing marks with the cams and crank. The motor turns over smoothly and there is no interference as it turns.

[mikes94q]

OK Still not running: Please Help.

I have pulled all relays and checked them, they are good.
the ecu pulls code 55
not sure what to try now.

When I reassembled the engine is it possible that the timing could be off? Would that cause it to not start?

Any suggestions at this point would help.

[djwarner]

Still feelin' for you Mike.

Is it a question of timing or actual spark generation?

If you remove one sparkplug&coil and ground it, a spark while cranking would indicate a timing issue.

[Q45tech]

Did you mark the exact position of CAS and reinstall it precisely.from extremes in slot you can change timing by 60 degrees +...................position must be accurate within +- 1/8".

[Infinitiguy19]

I have found instead of spending months sometimes sleepless nights its better off to save some money up and let someone else fix it. I was the same way with the power window fuse that kept blowing issue. Now my car's main harness has been hacked for life but the problem is fixed at least.

Problem with me is I over think EVERYTHING to the smallest detail (Rear Shock Tower Bar, J30 Keyless entry on a '92-'93 Q...). And I don't feel happy unless I make the stuff that goes in my Q. But sometimes you got to suck it up and let another guy look at it or take a break from your car and come back and maybe you will see the answer has been in front of you all this time.

[mikes94q]

Dj: No spark at all so maybe timings not it. I did order a new ignition control module to see if I was right but I just don't think those go bad at the same time all the sudden.

Q45tech: CAS? Crank position or the camshaft? Either way the answer is the same I'm not 100% positive it was installed correct. I followed the FSM but had a few items that were not very clear like the camshaft position sensor.

Side note from trying to start the car so many times, even after holding the accelerator pedal to the floor, I think gas is starting to make its way past the pistons into the oil. Is this ok? Prob not going to change the oil soon but is it causing any other damage?