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Car cranks but won't turn over... I have fuel/spark and timing is set!

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unfrgivn

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Discussion starter · #1 ·
I recently finished wiring up my car from scratch and I am now having a few difficulties getting the engine to turn over even though it should.

There is fuel running through the lines and they are hooked up correctly. I have spark at all 4 coil packs, the ignitor is tested and works, the ECU has all the right power and grounds, the engine is a "new" used engine with perfect compression, and I know everything is hooked up correctly as I have done many SR swaps.

I have checked the timing many times and the battery is good (I even had the car hooked up to another running car's battery just to make sure). It was just cranking and not turning over for the last few days. Today I checked timing one more time and even tried giving it some gas while starting and now it is doing something different. The car will crank for 1 second healthy sounding and then sound like it's getting stuck and dying and then go back to sounding healthy and repeat. I also took my egt sensor out of the exhaust manifold and I when I tried cranking again there was some black smoke coming out of the manifold.


Any help is greatly appreciated!
 
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#2 ·
please define perfect compresison for me, and do you have proof?

also, how did you check your timing? you cant check it with the car not running lol. i think you could just reset via the way onm p2m but thats it.
 
Discussion starter · #3 · (Edited)
Perfect compression meaning I had around 158 on all 4 cylinders. I would say that's pretty perfect. And my proof is I did the compression test mysely (I wasn't told this by the shop I bought it from)

I didn't CHECK timing, I SET it according to the FSM. I have set timing on these cars 1000 times I am pretty confident in my ability there. Took valve cover off, 1st cylinder at TDC, line up the marks on the CAS correctly, whalla.
 
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Discussion starter · #5 ·
geist said:
is ther fuel comeing outta the injectors and going into the engine? just cause theres fuel in the rail that dont mean shit.
Click to expand...
yes
 
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#9 ·
hate to get back to the timiing cause thats prolly the last thing you wanna hear seeing as youve done it 1000 times but you gotta be on the right stroke. as im sure you know. if you have compression, spark and fuel then the only other thing can be spark at the right time. its pretty easy to set the timing 180 degrees out. i know ive done it.


also you say spark at the coilpack but maybe your plugs are all fouled up from all the fuel thats not being lit. change the plugs confirm the timing again and start that SOB


even if the timing is out slightly it would still fire/start and run like a bag. the only way it wont start if you have it 180 degrees out. and then it fouls your plugs and when you do get it right the car still wont start cause the plugs are all fucked.

if youve done this 1000 times then do it once more
 
Discussion starter · #10 ·
I just set the timing one more time...

Valve cover off, spark plugs out, 1st piston at TDC (double checked with a stick), Timing chain had shiny link down at the crank and two shiny links up on the cam gears so it should be on the compression stroke (correct?). Placed the CAS in as shown in the FSM, put everything back together. Changed the plugs, gapped them to .028, tried to start the car again and it just cranks.

This makes no sense. How can I have fuel, spark, compression, and correct timing and no start? I'm thinking something is fucked with my ECU. I'm also gonna re-check fuel and spark and make sure in all my trying to fix things the last two days I didn't break something else.
 
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#11 ·
you are correct that the piston has to be at tdc but the motor has to be on the correct stroke. with the valve cover off watch the intake cam. turn the motor over and youll see the intake valves open and close the the exhaust valves will open and close and so on. so rotate it until the intake valves open and close, then youll only have to turn alittle more and youll be at TDC. this is where you want to do the timing thing with the CAS.

think of it this way. piston starts at TDC intake valves open as piston moves down to BDC drawing in fresh air. as piston starts moving up the intake valves close. the piston compresses the air and it is now at TDC again......now your spark happens at the right time and forces the piston back down. it reaches the bottom and the exhaust valve now open. the piston moves back up pushing all the exhaust gas out and exhaust valves close. The cycle is complete and the piston is at TDC again.

im thinking you have you motor at TDC at the wrong point in this cycle. i did it once by accident and had the same problem you did. it will not start.

i dont know about the shiny marks on the timing chain i just go by the valves. and im pretty sure you know how a motor works too but i felt like typing it anyways
 
Discussion starter · #12 ·
Yes I am aware how the valves works, the FSM says to looks at the marks on the timing chain though so I always follow that. I guess I can try one more time... not like it takes that long.
 
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Discussion starter · #14 ·
Yes my fuel pressure is good.

and as far as the pump goes... fuel is flowing at 1L/11secs, so I don't know what it should be, but it looks healthy.
 
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#15 ·
well man thats a tough situation. if everything you are saying is correct than it should run. fuck...if you gave a potato fuel spark and compressions she'd fire up. you said you had wiring difficulties....maybe have another look there.

maybe put some gas in it?

maybe check the intake manifold for a blockage. a shop rag or something?
 
#16 ·
Have you checked to see that you are getting a signal to the injectors from the computer? Just cuz you have fuel pressure, compression, and spark does not mean there is any fuel in the cylinder..... spray starting fluid into the throtle body while trying to start the car and see if it starts then.:thumbsup
 
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