hot air wont start

white 86 t

New Member
Joined
Sep 28, 2015
I just installed a new camshaft in my 84 put it all back together and no spark

checked crank sensor and its good, cam sensor is also good and checked swapped coil packs still no spark have fuel pressure at the rail
 
Crank sensor good? There's also an electronic spark control module you might want to check. Good luck
 
Same problem here, ready to change coil pack. Where is the spark control module and how do you test?
 
Same problem here, ready to change coil pack. Where is the spark control module and how do you test?
I believe it's on the inside passenger side fender not sure how to test it it's probably cheap to get a new or known good one
 

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Power at ignition module?
What ignition module and crank sensor are you using?
Crank sensor/interrupter ring going through the correct slot (farthest away from the wires)?

The spark control modue rarely goes bad.

The Basic HA info sticky has a "No start" tree link. Can you give that a try?
 
I found a bad female connector pin on my coil pack connector one time,pulled it back out and it fired right up.
 
i checked the crank and cam sensor they are good i used this from the site module on pass fender also good. does anyone know what wires are supposed to be hot at coil?



You'll need to get at the ECM and the cam & crank sensors to do some voltage tests. If you have a NEEDLE type voltmeter, it may work better for these tests, as it will visibly "swing" when the sensor switches open & close (IF they're working okay!)

Here goes:

First, test your meter and ground! (see ECM Plug) Check connection A-6, "ign, ECM fuse" for 12 volts. (for ALL tests, BE SURE the negative lead of the voltmeter is connected to a GOOD GROUND!)

#1- (see ECM Plug) With the key off, disconnect the ECM A-B connector. With the positive lead of the voltmeter, probe the B-5 connection (highlighted yellow, this is the crank sensor signal) Crank the engine and watch the meter...you should have varying voltage from 1 to 7 volts.
If NOT okay, proceed to #2.
If you ARE seeing correct voltage, your cam & crank sensors are okay, and your coil and/or ignition module may be the problem! You need to loosen the coilpack, and check the BLUE wire for 12 volts, key on. If it DOES have 12 volts, then the problem is likely the ignition module.

#2- now probe the A-11 connection... (highlighted green, this is the cam sensor signal). Crank the engine...you should have varying voltage from 1 to 9 volts.
If it IS okay, THE CAM SENSOR IS FINE, AND YOU ONLY NEED TO TEST THE CRANK SENSOR IN ALL FURTHER TESTS!
If it's NOT okay, there's no cam sensor signal!

Plug the ECM connector back in, and head for the sensors!

#3 (see "Sensor Plug") Unplug the cam sensor plug. Turn the key "ON" ...On the MODULE SIDE of the plug, probe the "A" wire for voltage, after which probe the "B" wire for voltage. You should have between 5 and 11 volts on BOTH wires.
If you ARE seeing correct voltage, THEN: with the negative lead of the voltmeter, probe the "C" wire, and with the positive lead probe the "A" wire. You should have between 5 and 11 volts. Note the results, then REPEAT THIS TEST WITH THE CRANK SENSOR PLUG!

If ANY of the sensor plug tests FAILED, you have a probably ignition module problem...
If ALL the sensor plug tests PASSED, then PLUG IN the sensor plugs, and proceed:

#4. Test the cam sensor: Probe the "B" wire of the cam sensor, then crank the engine and watch the meter. You SHOULD have varying voltage between 1/2 and 9 volts. REPEAT THIS TEST WITH THE CRANK SENSOR!

If either sensor fails this test, then it's possible that sensor is bad! If they PASS this test, it's likely the ignition module, or the connections TO the ignition module are bad)

Hope this makes sense!
 
Check your coil pack,
I tested my coil pack and one tower was dead. I replaced the coil pack along with the 7.5 amp fuse that kept blowing with the old coil and it fired up immediately.
 
Check your coil pack,
I tested my coil pack and one tower was dead. I replaced the coil pack along with the 7.5 amp fuse that kept blowing with the old coil and it fired up immediately.


I just tried 2 other coils and all my fuses were good under the dash still nothing
 
I'm certainly no expert, but with all the reading and research I have done lately it might be your Ignition module.
 
Take a volt meter and check the resistence across the coil. I did this with the new one (at the kitchen table) I got from advanced auto. All read the exact same number around 13. I went out to the car and did the same thing and two of them read up around sixteen and the last one had no reading whatsoever.
Put the new coil in and BAM it fired and started up immediately.
 
OP,
I can sense your frustration and merely trying to help so don't take this the wrong way.

Based on your screen name . . . I am sure you know the module wiring on the HA vs IC is different?
If you hooked up an ic module without the correct wire routings, something is fried.

You tried the cam and crank sensors and "they are good".

How did you test these?
Are you missing spark and/ fuel? Did you verify the crank sensor is installed correctly? What module are you using?
ECM power wire plugged back in at the battery?
 
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the basic hot air info is what i used to test my sensors. verified that the cam sesor is in right i also have injector pulses
 
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