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350 WON'T START

  
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350 WON'T START

 
1994_chevy_350 1994_chevy_350
New User | Posts: 4 | Joined: 01/13
Posted: 01/26/13
12:23 PM

hi i have a 1994 Chevy Silverado with a carburated  350 30k over  that was put in about 4k miles ago most everything on it was new and now it wont start just died at a stoplight and i had it towed home and im completely lost as to what the problem could be i tried to put in carb cleaner in it pored flue in the carb and still nothing where do i go from here ?? thank  you for your help if i need to post anything else about it let me know. i willl  

tuffnuff tuffnuff
Moderator | Posts: 7827 | Joined: 12/09
Posted: 01/26/13
12:48 PM

Are you running an HEI distributor? If so then your module may be fried.
Do you have any spark?

Smile  
When The Flag Drops.,.

tuffnuff

The Bull ***t Stops.,.
tuffnuff

P. Engineer, Engine Builder

68scott385 68scott385
Guru | Posts: 1990 | Joined: 10/09
Posted: 01/26/13
12:57 PM

Go back to the basics...

Does it have good compression in all holes?

Does it have/get spark?

Does it have/get fuel?

I've seen clogged fuel filters/lines do this.

I've also seen, at least twice on my vehicles, the HEI modules die not signal spark. I've seen, on more than one occasion, the rotor have one problem or another and not pass spark to the right place even when it is visibly undetectable.  
68scott385 68scott385 68scott385

1994_chevy_350 1994_chevy_350
New User | Posts: 4 | Joined: 01/13
Posted: 01/26/13
01:12 PM

its an ACCEL GM HEI In-Cap Super Coil 140003 i believe the sticker is a little worn on it  

1994_chevy_350 1994_chevy_350
New User | Posts: 4 | Joined: 01/13
Posted: 01/26/13
01:28 PM

what kind of module do i ask for at the part store?  

tuffnuff tuffnuff
Moderator | Posts: 7827 | Joined: 12/09
Posted: 01/26/13
01:34 PM

Take the module with you to the parts store.
You can try pouring a little gas down the throttle body.,. see if it fires or tries to fire.
If nothing happens then it's most likely a faulty module.

Smile  
When The Flag Drops.,.

tuffnuff

The Bull ***t Stops.,.
tuffnuff

P. Engineer, Engine Builder

1994_chevy_350 1994_chevy_350
New User | Posts: 4 | Joined: 01/13
Posted: 01/26/13
03:46 PM

tried that its not the module and when i pored gas still nothing im lost...even tried a new module and still nothing  

68scott385 68scott385
Guru | Posts: 1990 | Joined: 10/09
Posted: 01/26/13
05:29 PM

You can pour gas in it all day but if it isn't getting spark you're wasting time and gas.

Why do you have to pour gas in it. If the carb/throttle body is working correctly you don't have to pour gas in manually.  
68scott385 68scott385 68scott385

waynep71222 waynep71222
Enthusiast | Posts: 448 | Joined: 03/12
Posted: 01/26/13
07:41 PM

well... lets look at diagnosing the ignition system

hopefully since its been hours since your first post.. you have it fixed but if not..


do you have a TIMING LIGHT...   and a CIRCUIT TESTER/TEST LIGHT...


with a timing light.. clip it around each spark plug wire one at a time while you have a friend crank the engine.. or while you crank the engine if you have tape or rubber bands holding the trigger on.. so it flashes without you holding it.. this would indicate that you have some kind of spark..

if you GET NO indication from the timing light..

you might want to use your test light hooked to ground.. and PROBE the BAT Connector/wire on the HEI cap...   you should get power as soon as the helper turns the key to the ON position.. and still while you are cranking the engine and still when he releases from the cranking position to the ON position... this proves the power is getting thru the ignition switch and wires to the HEI...

this is an important test above..  i had to drive from LA to palmdale to rescue a friend who's only problem was the HEI power wire fell out of the cap...   it was only 140 mile round trip..  and i had warned him that the terminal body needed replacing as it was broken...


if you don't get spark at the wires...  but DO have power at the BAT terminal on the cap...

pull the cap.. then the rotor...   turn the rotor over...  examine the bottom for signs of burn through...  my automotive tool man.. truck full of tools.. had his truck die.. he replaced the module.. the pick up coil.. the ignition coil .. the cap...  it still would not run...  he never bothered changing the ignition rotor.. the chevy dealer did..   5 bucks parts and a 300 buck tow and it was running..


say.. pull the cap... but look at which way the rotor is pointing .. reach in and crank the engine for a split second.. did the rotor change directions..   try not to wind up the wiring or spark plug wires in the spinning rotor...  this verifies that the timing chain and distributer gear are probably OK..   if you bring the TIMING MARK on the harmonic damper to TDC..  the rotor should be pointing at either the #1 or the #6 spark plug wire position on the cap... you will have to determine where those are as distributers can be installed in a bunch of directions..   only one is technecly correct so the spark plug wires fit perfectly..


now.. the module....  its probably a 4 pin GM module..   many parts stores have testing machines for them...

you can check the PICK UP coil with an ohm meter...  set to 2K ohms...  500 to 1500 OHMs is expected...  usually around 980 is where you find it..  before you disconnect the meter.. flip it over to 2 volts AC... or 20 Volts AC and either spin the shaft or have somebody crank the engine.. you should get just over 1.0 volts AC or something very close to it..  if the pick up coil has failed.. or the microscopic wires have failed.. it may fail the resistance test.. and also fail the AC voltage output test..

you might also want to pull the cover off the top of the distributer cap.. if yours has the coil in the cap...    verify the sides of the coil show no signs of high voltage leaks...

Coilhighvoltageleakareas

COIL Highvoltageleakage

please go thru this step by step...

post what you find...