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-   -   No Crank or No Start (https://forums.turbobricks.com/showthread.php?t=316437)

ZVOLV 12-15-2015 09:15 AM

No Crank or No Start
 
NO START:



http://cleanflametrap.com/breakerles...s/image066.jpg

Photo courtesy of cleanflametrap

- STEP 1: Check for spark! Safest for you and your car is a timing light, but without one, unplug ignition wire going from the coil to the distributor. Ground it very close to a strut tower stud like in the picture above. Crank the engine. Do you see spark? If you see a consistent spark, go to the next step and do the starting fluid test. If no spark, inspect Crankshaft Sensor/Hall Sensor and do ignition diagnosis.

-STEP 2: STARTING FLUID! This will confirm that ignition, timing and mechanicals of the engine are good with one fast and easy test:

TO USE STARTING FLUID: Unplug the fuel injectors, pull the spark plugs and clean them of any fuel, crank the engine and air out the cylinders. (This will clear out any flooding of the cylinders from trying to start the engine.) Then reinstall the spark plugs, LEAVE INJECTORS UNPLUGGED, disconnect intake hose at throttle body, open throttle body, give it two long sprays, crank. Start? If so, you have a fuel system issue. YOUTUBE VIDEO ("test fire without any fuel lines even installed in the car yet.)

If your car runs on starting fluid, the fuel system is suspect. Check for 12v at the fuel pumps/fuel pump fuse with the engine cranking. Check fuel pressure. A gauge that will bolt onto the fuel filter outlet (12mm banjo) is available from auto parts stores for a refundable deposit.

-Nothing wrong with doing a compression test!

-Check belt timing. The cam, crank, and aux shaft (on 240) all need to be aligned correctly.

-Check ignition timing. Approx 12 degrees BTDC.



NO CRANK:

1: Battery above 12v?

2: Still no crank? Backprobe yel/blu wire at starter. Crank. Have 12v? If not, neutral safety switch (if auto) or ignition switch suspect.

3. 12v at signal wire to starter and STILL no crank? Starter, battery, primary/ground wire issues.

mikep 12-15-2015 05:19 PM

Quote:

Originally Posted by ZVOLV (Post 5298071)
DISABLE IGNITION OR FIRE WILL HAPPEN, and point fuel rail into the air and crank engine and you should see injectors spray. This will tell you that the computer is working and you also have some fuel pressure.

Not a good idea for newbies to do this. Fire can still happen, and you can tell just as much by testing the signal at the wires.
If you rule out all other problems and have poor cold starting and idle, take the injectors to have the pattern checked, or do it the way you describe in a container of some sort.
Trust me, I have seen fires and other silliness with ignition disabled.

ZVOLV 12-16-2015 12:11 AM

Crank Sensor Diagnosis
 
Do you think your crank sensor is bad?

Peel back rubber insulation on crank sensor connector at firewall. Backprobe the center wire, red/yellow, pin 2 with one lead, send other lead to battery ground. Multimeter to AC Volts, NOT DC, and crank engine. You should get approximately 0.4V AC cranking.

-Backprobe between Red/Yellow center wire and Blue/Yellow (pin 3). Check resistance. Spec should be around 200ohms (further data needed. Can vary), but if you see an open circuit here, sensor is bad.

Plus T 12-18-2015 03:39 PM

Quote:

2. Locate fuel pump relay. Remove cover. Turn key on and watch contacts. The FIRST contact should close with key on and STAY closed. This is power for the computer system. SECOND contact is for the fuel pumps. It may/may not prime with key on. CRANK ENGINE. SECOND contact should close and also STAY CLOSED. If it doesn’t, you may not have a crank signal. Check hall effect sensor or crankshaft sensor. If the first contact EVER pops open with the key on, time for a new relay. Also check for corrosion at fuse panel and also at fuse at battery (if equipped)
I dont understand. How can you tell if the contacts in the fuel pump relay are opening/ closing? Do you have to take apart the relay and look inside it?

ZVOLV 12-19-2015 12:29 AM

Quote:

Originally Posted by Plus T (Post 5300512)
Do you have to take apart the relay and look inside it?

Yes.

Plus T 12-19-2015 01:10 AM

Wow that is very helpful, I would have never known. That will definitely come in handy for working on my 240. Thanks.

ZVOLV 12-19-2015 01:24 AM

...

PardoR 02-22-2016 01:30 PM

My car, after passed the shop runs fine but it can't start. It cranks OK ,it has spark, new rotor, new spark plugs, fuel pumps working fine, distributor works, injectors OK, FPR new... Ehat else can be??

Otto Mattik 06-25-2016 04:51 AM

Quote:

Originally Posted by PardoR (Post 5343671)
My car, after passed the shop runs fine but it can't start. It cranks OK ,it has spark, new rotor, new spark plugs, fuel pumps working fine, distributor works, injectors OK, FPR new... Ehat else can be??


CPS ?

Jimmy E. James 08-31-2016 12:11 PM

Quote:

Originally Posted by Plus T (Post 5300512)
I dont understand. How can you tell if the contacts in the fuel pump relay are opening/ closing? Do you have to take apart the relay and look inside it?

Don't have to open any relay to test
Use DVOM, high impedance, on computer side circuits and test light for B+ and switched
Good "T" pins for plug back probes also make it easier
Also test for good ground(s) to relay, like one for RSR if voltage/trigger is good

Jimmy E. James 08-31-2016 12:26 PM

Quote:

Originally Posted by PardoR (Post 5343671)
My car, after passed the shop runs fine but it can't start. It cranks OK ,it has spark, new rotor, new spark plugs, fuel pumps working fine, distributor works, injectors OK, FPR new... Ehat else can be??

How can run fine if won't start?
Anyway
Three parts of equation - FUEL FIRE COMPRESSION and all at right time
If injectors are pulsing and you have fuel on rail next thing to check is that the engine has compression if everything else you say is fact
Remove oil cap and look in hole to see if cam is turning while engine is cranking or being turned over by hand
If not turning it is seized up or your timing belt has broken


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