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Discussion Starter · #1 ·
i just got my motor back in my car and ready to go, i double checked over everything a few times before i tried to start it, well i start to crank, i have fuel guage hooked up as well as a spark tester, i got fuel pressure, but i don't get any spark at all, any gimme some ideas on what i may have missed, or what i should do?
TIA
 

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Check for 12 volts to the ECM. Check cci fuse, and the orange wire feed off the battery to make sure that is connected. read the following all the way through for more ideas..

Let us know what happens!

1) Go to radio shack and spend $16.00 on a logic probe.

1.5) Verify 12v on pin M, pink/black wire coming from CCCI fuse.

2) At pin G of the ignition module, a dark green wire, backprobe with the logic probe and have a helper crank the car. If the logic probe blinks, the crank sensor is good. If no blink, then check for 12v at pin F, which is a gry/red wire. If you have 12v, verify a ground on pin H. If ground is good and you have 12v, then the crank sensor is bad. If you dont have 12v on pin F, the module is bad or the CCCI fuse is bad (Or a wiring problem between the fuse and module of course.)

If you have crank signal but no spark, the module is bad.

If you have crank signal, go to next step.

3) Using your logic probe, we'll check for cam sensor signal. Probe pin K, light blue wire and have a helper crank the car. Mind you the light will only blink every TWO revolutions. Let it spin a couple times to make sure the sensor hits every time and that its not flaky. If you have no puilse, verify 12v on terminal M, gray/red wire, and gnd on term L, black wire. If either is missing, the module is bad, or the CCCI fuse is blown (or the feed wire is open).

I doubt its the cam sensor because like I said, the ECM will NOT cause a no spark condition.

I think by now you will have found the problem, but if you want to go on...lets say you have ckp and cmp signal coming into the module. Now were gonna check it coming out.

Terminal C, a ppl/wht wire is ckp hi and is the signal used by the ECM. Backprobe this wire with your logic probe. Have a helper crank the car and look for blinky-blink. If no blinky-blink, then the module is bad. If blinky-blink, go to ECM pin B5 (ppl/wht) and verify the same thing. If you got blinky there, lets check for cam signal.

Go to module pin J, yellow wire, and verify the blink every 2 revolutions. If no blink, the module is bad. If blink, go to the ECM pin A11, yellow wire. Check for the same blink every 2 revolutions. If no blink, then theres an open in that wire between the ECM and module. If you got blinky, hook up yer scanner and crank the car while watching for RPM. If no RPM reading, and you have cam and crank signal, then the ECM is bad. (It wouldnt be the ECm fuse or power feed, cuz you have a data stream, proving the ECM has powered up) If you have RPM reading but no injector pulse (probe the opposite of the BROWN wires at the injectors. The brown is the power feed and the ECM grounds the injectors to fire them.) If you have RPM signal, but no pulse at the injector, then the ECM is bad.

BUT again, the ECM will NOT cause a no spark condition. So I doubt this is the case with your car.

At this point, your car should either be running, or on a tow truck destined for the junk yard as it defies logic

All the wiring diagrams you need are on gnttype. I know cuz I put them there. If you were closer, I'd get it running for you. Shouldnt take more than 1/2 hr to figure out whats wrong, and you wouldnt have to have a spare crank sensor and spare ignition module in yer garage.

This was posted By Turbo_Tim:
"The following was written by Jim Testa and is a very logical means of troubleshooting a no start. Looks like you are ready to begin step 3. Hope Jim's info helps you. It has helped me many a time.
"OK, to diagnose ANY car, you need to find what you have and dont have. The way *I* usually go about it (which might not be right to some people, but its methodical and consistant so I stick to it.

1) Note the check engine light (if EFI). If its not on, STOP and find out why. Listen to how it cranks. I can pick out compression problems doing this. If you are in tune to your car, you can too. Listen to the starter as each cyl comes up on compression stoke. You'll hear the starter slow down a little at that point. You bight hear deerdeerdeerdeer, where a dead cyl m ight sound like deerdeeeeedeerdeer (great sound effects huh?)

2)Depending how accessible the intake is, I'll shoot 3 or 4 seconds of carb cleaner into the plenum. Either thru the throttle body, or the brake booster vacuum port. If its a lack of fuel problem, the car may start, it may simply kick. If it does either, its time to look to fuel system (usually, although enrighening can bring out a low sec output problem too, so dont take my suggestion of fuel as law)

3) If the car kicked, I'll put a FP gauge on it. If fuel pressure isnt in spec, now you need to see why. Fuel pump, filter, resticted line, bad reg, low batt voltage, bad relay, blown fuse etc. If FP is in spec, its time to hook up a noid light and verify our injectors are getting pulsed. If youre not getting a pulse you will want to hook up a scanner and look for RPM during crank. If you are getting RPM signal, check for spark. If you're getting spark and no fuel, although there is a commanded PW (see below) you probably have a bad ECM. How fast it cranks isnt as important as the fact you get a RPM signal. Next you'll look at Coolant temp to see if it coincides with ambient )if the car is cold), and verify TPS isnt shorted to Vref which will put the car in clear flood and cut off fuel. If these all look OK, you'll want to take a look at commanded PW.

3) If the car didnt kick, I'll yank a plug wire and see if I got spark. If I got no spark, then I'll check also for inj pulse using a noid light. If I have neither its usually due to a dead crank sensor. If I have no spark, but I have injector pulse, its usually a module.
Typically:
No start - no spark, has inj pulse -> Module
No start - has spark no inj pulse -> ECM / cam sensor prob
No start - no spark OR inj pulse - crank sensor or module

Oh, and if the module is dead, I suggest putting a coil pack on it as well as most of the module failure are caused by an overheating or arcing coil."
 

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Tim, which probe, what voltage, where do you connect it?
 

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Ok, here is what we need to know about logic probes. (Hey I just copy and paste this stuff :) )

A Logic Probe is one of the basic troubleshooting tools for common electronic logic circuits (TTL circuits, chips with the 74XX pre-fixes). Almost all video game circuit boards are built using TTL chips. These chips will occasionally fail and the Logic Probe is a tool that affords us a look into what may be failing. Logic probes are fairly inexpensive about $30.00 from Jameco, Radio Shack or the like. Logic probes have their shortcomings too...

most operate at less than 20 Mhz. Pac Man's main frequency is 6 Mhz and most older games are under this ceiling of 20 Mhz.
they only indicate state changes, it is up to you to know if they are the expected changes.
Logic probes derive their operating power from the PCB under test, probes have 2 power clips Black for Ground & Red for +5VDC. Care should be taken in attaching the clips to safe voltages; you may want to first use a Volt Meter (Digital Multi Meter) to verify the hook up points have good voltages. (Actually if you are at the point of using a logic probe you SHOULD have already verified the board under repair has good voltages.)
Logic Probes have 3 LED's and some have a Piezo buzzer. The 3 LED's indicate...

RED High logic state a binary 1. TTL chips consider +2.4 to +5 VDC to be high.
GREEN Low logic state a binary 0 TTL chips consider 0 to + 0.8 VDC to be low.
YELLOW Pulsing state (yellow &/or piezo buzzer)

(End of copy and paste)

Ok, I'm back! *G*

Steve I have been looking for the pin-out voltages on the gnttype site, and can't find them. Maybe you can find them? I'm pretty sure there is a 5 volt lead there that one could hook a logic probe to....
 

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okay, I knew what a probe was but I also know that most are 5 volts but there are some that can accept more voltage.

TPS reference is 5 volts so that is an underhood location, I believe.

I was hoping that Jimmy T would show up as he wrote the blurb you quoted. I used to own a scope but it was liberated from my shop along with my compressor and tools awhile ago. After that, I just went to a friend's and used his. No such people around here. frown
 

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Discussion Starter · #10 ·
ok, heres what i did, got a noid light from work, i got no injector pulse or spark, i checked all the fuses and powers, all ok. soo ii have a crank sensor on the way.. hope this solves my problem, any more ideas??
 

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Yes, have a beer and relax until the crank sensor gets there. :) 30 thousandths clearence when you install it. I guess you decided that a logic probe was almost the same price as a crank sensor, so might as well get the sensor, since if it is bad you will have to buy it, as well as the probe. :) What the heck, it soounds like you are on the right track. Nothing wrong with having an extra crank sensor in any event.

Let us know ho things work out.
 

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Turbo_Tim:
Steve I have been looking for the pin-out voltages on the gnttype site, and can't find them. Maybe you can find them? I'm pretty sure there is a 5 volt lead there that one could hook a logic probe to....
If you can't find any 5 volt DC sources.
Use an old computer power supply.
They run 5 and 12 volts.
The Red Wire on a Comp Power Supply runs 5 (my testing of a PS showed 5.14) volts.
The Yellow wire (orange in older PS) runs 12 volts. (my test showed under 12)
I don't know whether amps plays a part in it or not.
Just remember that if you use the 5 volts from under the hood to hook a ground to something on the car.
Same for the Power supply.
Red wire 5 = volts.
Either black wire = Ground.

I only state this as common sense.
I've heard of situations where someone hooked ground to 1 thing a positive to another and wondered why they didn't get a reading.

HTH -Matt-
 

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Thanks Matt, but the TPS uses 5 voltage as a reference voltage. I believe the voltage originates from the ECM. wink

Next thing is to get a list of the pin-out voltages. There used to be a chart on gnttype, but I can't find it now :mad:
 

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Get a shop manual! :)
 

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Thanks! :)

Use the new bracket. Save the old one just in case the bracket ever breaks.
 

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Discussion Starter · #18 ·
ok i put my new crank sensor on tonight, set it at .030, go to start it up and still have no spark or injector pulse, so my guess would be that the ignition module is junk?? this car hasn't run in about a year, would it sitting that long cause the module to crap on me???
 

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Does the tach move when you are trying to start the car?

sitting should not hurt the module.
 
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