No Spark, but everything tests good

[Crazybobmundo]

I just finished my engine rebuild and put everything together.
When I cranked it I figured it would take a while and build pressure in the gas line but it doesnt even start at all.

I started checking everything, the normal checks, until I found out I wasnt getting spark.

After finding out my problem I started doing the TSRM diags of:

a) Ign Switch
b) Igniter
c) Coil Packs
d) CPS
e) and harness

oh and grounds.

EVERYTHING, I mean EVERYTHING tests ok. My resistances are 167 on the plug side of the CPS, my coil packs arent short grounded, my harnesses are continuous...Im stumped.


I usually just search and get enough info to figure out my problem but I am sincerely stumped.

Ive even swaped every component from a running supra and Nothing!

Can anyone help me. Maybe theres something that might be testing ok but actually be bad? I mean this is very bizzare.


BTW my car is a 90 Turbo.

 

[Crazybobmundo]

I forgot to mention I swaped ECUs as well. Still nothing worked.


Now Im getting Code51 before that it was 51 and 14. I fixed 14 by fixing a ground wire that wasnt grounded.

 

[Bri7man]

I'd make sure no fuses are blown and I had the same problem as you and it ended up my cps was 180 deg out.

 

[Another MkIII]

Yeah, my CPS was off just enough that it wouldn't start. And I had a missing fuse. The PO took it for something else, so I checked all my fuses, they were all good, it was just one was missing. That's one you don't expect and feel like a dumbass for not finding sooner. lol
-AM3

 

[Crazybobmundo]

Ive done that. I thought maybe I was missing a fuse and even replaced the IGN fuse with a brand new one just incase.

I do get power to my igniter from my ignition switch, I am getting power to the coil pack harnes from the igniter and the coil packs are good atleast according to the multimeter.

Ive swapped coil packs suspecting that they just test good but arent actually good at all. Still no spark.

WOuld I be getting a code if the CPS harness had a wire with a break in it?

I think Im going to check for continuity on that part of the harness, I dont recall checking that.

I forgot to mention as well that my RPMs dont move when I crank the engine. I read somewhere that usually that means that theres a problem with the CPS...

Im really getting aggravated.

Thanks for the pointers guys.

 

[Crazybobmundo]

So in trying to figure out this bizzare problem of mine my brother and I discovered an odd solution.


The EFI main relay. Has it been known that this relay is part of the ignition circuit?
I sure as hell didnt know, and its not mentioned in the TEWD.

The way we discovered that is I got a code 11 and went from there. I swaped relays with my brothers running supra and mine still didnt get spark.

I went to start his car to check something different but it didnt start. It had the same symptoms as mine. No spark, RPM doesnt move, Just cranks.

So I made extensions with bigger spade connectors thinking that maybe the female connections on the fuse block fell or something....


Viola! My car started, my RPMs moved!....but for a few seconds then it died.

I got so F-ing pissed because it wouldt start again, no more spark.
Now that relay doesnt work AND I cant figure out why this is happening. Even with the working relay it doesnt spark.

I guess now Im going to chase that circuit and see if I can figure out the problem. But I need a break. I have a headache and I want to drive my car..

 

[Bri7man]

I dunno about that but with my cps out 180 deg my car started once about every 20 tries being on the exhaust note on that start. It would die very shortly after that. I guess you could have electrical issues but once I turned my cps around 180 deg from that position it started every time but i guess you already addressed this.

There is one tdc mark on the harmonic balancer but this does not mean the first cylinder is tdc if the harmonic balancer is at that mark. It could be down and you need to do one more full rotation to bring it up. Put a long dowel in the first spark plug hole and when the stick is at its highest, that tdc mark on the harmonic balancer is true tdc.

Dunno if you already knew about this but you're symptoms still point to this isssue I had.

 

[89supra7mgte]

Have you checked all engine grounds? I had a similar problem with a completely different car, none the less tested and checked everything for a day and a half, found out that i had a bad ground, just bad enough that fuel and everything would work but the spark was so weak you could not see it and it would not run. just a thought.

***** Sorry just re read the post, and see you have checked grounds my bad, but not bad to recheck with test light on positive terminal and touch to block.

 

[T-MA71]

We're wondering if there could be a short in the fuse block itself?

 

[Crazybobmundo]

So today I went to the junk yard looking for A fuse block to test if it works.

I installed it when I got back but nothing happened, again. SO I said F- it Im putting everything back on and finish everything else thats left on the car and maybe taking a break Ill figure out the problem.

Once I installed everything back to the way its supposed to go I had this temptation to crank it again...Well it started but it reved like crazy! I cant control it now, it starts then dies.

As soon as it starts the RPM's rise really high, then drops then dies.

I held the gas a little to check timing with the light but its WAY OFF. I can rotate it in any direction and I cant get it close to any degree marks. SO I have to take it out and re-install it.

Now I have to replace some siding, I didnt realize how close I was to the house and I think I shot some flames in the process...The siding is all melted.

 

[89supra7mgte]

Damn that sucks. So it is the cps i take it? I have had to pull mine out multiple times. I had mine one tooth back and one tooth forward never had a no start but did have a bad miss, ran on 3 cylinders, and would die after throttle. There is a post on here somewhere, of exactly how it should line up. I tried the tsrm way and could never get it like they show. Its very helpful and when you have it out double check the air gaps i believe they should be .008 to .012, check tsrm to verify though, and they are adjustable as well

 

[Crazybobmundo]

I decided to time it tonight. I have a problem now.

When the car starts initially the RPM's rise rapidly. When the RPMs finally drop the car idles lvery rough, and occasionally reving itself.

Im running super rich, getting some flames out the back and even what look like fire flies. I also get this back fire form the intake. I even got a random weird spark on the firewall. I even have it on video, Il post it up soon.

I dont know what it is now. Im really getting sick of this car and just want to drive it.


If it helps.
I have RC 550s
AEM fuel pressure regulator
LExus AFM

maybe thats where my problem may be. Anyone please help.

 

[89supra7mgte]

have you checked for any vacuum leaks? the high rev sounds like you pullin in more are possibly. have you checked codes? what fuel psi are running

the sparks and flames almost sound like the timing is way too advanced as well

 

[Crazybobmundo]

Yeah I did check codes.


Originally I was getting 14, and 51. Then I cleared 14 and was getting 11, no 51.

I guess I fixed 11 when I swaped out the Fuse block and now Im just getting 51.

This car is haunted I swear.
My little brother said that when he was watching us working on it and said he saw sparks underneath the car on the passenger side going from the front wheel to the rear.
WTF does that mean? I hope it was the reflection of a blue car or something like that. Hes only 7 but he swears he saw sparks.

Hell, I saw a spark that just appeared on the firewall! Im about to pour gas on it and light it.

 

[89supra7mgte]

yeah have homeowners cover it lol. Have you had someone in the car to start it as you watch to see the spark to try and determine where it is coming from? what location of the firewall is it at? I know this is a dumb question but do you have the correct firing order on the coil? 163425?

have you found any vacuum leaks?

post that vid lets see what it looks like

 

[Crazybobmundo]

Fuel pressure is at 40 without vacuum. Even after I install vacuum it stays at 40. Should it change?

 

[89supra7mgte]

Yes is should change it should drop down quite a bit, tsrm i believe says with vac it should be 23-32, might wanna check and see. Is there fuel in the vac line? can you feel vac on that line when unplugged? you def have an issue there with that. If the diaphragm inside the reg is bad you will have fuel come out of vac port. but it could also be stuck for various reasons. If you have a vac pump apply vac to it and see if psi drops. you are using the stock fuel system correct?

Was the firing order correct? Did you find hear or see any vac leaks? what could be happening (anyone feel free to correct me please) is that the high pressure is loading up the cylinders and causing detonation creating the flames, the "fire flies" can be anything that is hot, carbon deposits, bits and pieces of anything that is in or on the combustion chamber. I have seen it happen where it was actually small pieces of the valves and plugs (v-8 with 12.5:1 compression that was out of time and running way too rich)

 

[Victor Charlie]

Once I installed everything back to the way its supposed to go I had this temptation to crank it again...Well it started but it reved like crazy! I cant control it now, it starts then dies.

Try the throttle position sensor on the throttle body. A similar issue came up with my car a few days ago and JJ pointed out that you can't set the timing with a code 51, so that would explain your timing problem. When i was messing with my car at one point I took of the TPS and installed it incorrectly, it was misaligned so that it was loading the throttle valve spring a little rather than the throttle valve prongs moving the TPS as the throttle was depressed. In this misaligned state the care would sometimes start, race furiously for a moment, and then die, or almost done, when it was set just so it would cycle from revving to barely turning over every few seconds. Once you are sure the TPS is installed correctly, check the voltages at the ECU according to the fuel injection section of the TSRM.

If it runs strong, even briefly, it probably has good ignition components. You can check for fuel pressure by Jumpering the fuel pump at the test block and pinching the fuel return line. It is obvious when there is at least decent fuel pressure. If that checks, and swapping ECU's didn't work, then I would think it is the inputs into the ECU messing you up.

 

[T-MA71]

Heres the video. Were supposed to work on it today, but it looks like it might rain. But anyways, here it is.

Theres more videos that im uploading now.


http://www.youtube.com/watch?v=9hOvwD16160

BTW theres no one revving it in the car. It's doing it itself....

 

[Bri7man]

I'm at my school library so I couldn't hear sound but my car had crazy idle with a misaligned tps. Adjusting it forward and back does affect constant idle rpm's and I had to get that adjusted before I set the timing and once I did she purred normally.