I have a 1985 Chev20 Van with a 305. I have power entering the Cap/Rotor but no Spark. I have changed the Ignition Module and the Coil Pack on top of the Cap....all to no effect. THe Engine with turn over but has no spark coming down the wires whats so ever. Any Help will be greatly appriciated.
No, I would suggest the magnetic pickup in distibutor first. (I do not think it is the rotor here)
----------------- TheSnoMan.com
No, I am talking about the pickup coil in the base of the distributor that send the trigger signals to the coil to fire spark. It is next to the 8 lobed reluctance "wheel" that triggers it as each lobe passes it.
----------------- TheSnoMan.com
sorry about my spelling. I can spell like crazy, but have been sick for 5 days and my typing is off. old john\
SnoMan, thanks for the replies...and I know what you are talking about now...after I read your reply I went home and a buddy and myself went and replaced the pickup coil (I had thought it was a condensor). Still no spark. This van was completely gutted and repainted a year ago and hasn't been started since. I did notice though....a harness located under the drivers seat with nothing attached to the end of the harness. This harness then goes under the floorboard...back to the Cap/Rotor. I beleive I am missing an important computer or module for this van. I remeber taking it out over a year ago and noticing it was rusted to heck. Perhaps I threw it out...I cant remember. Basically...what is this box...is there a way to by-pass it...or am I holding on to a huge boat anchor?
Sound like you shucked the knock/spark control module. You need to replace it.
----------------- TheSnoMan.com
THe Knock/Spark control module....is this one componet located under the driver seat? THis is on a 1985 Chev20 Van...with a 305 cubic inch. I want to make sure I know what the exact name of the part is...and where I might be able to obtain a used one. Thnks agian for all of your help.
Well on a TBI P/U it is mounted on engine intake on a bracket and it is maybe 3 x 3 x 1 inches. In a van, space is tight and it could well be located beneath the seat. Get one at like Advance Auto and you can take it back if it not it. Sorry that I cannot be more exact but I do not have a van here to look at to see for sure. It will not make spark without one though
----------------- TheSnoMan.com
Hey Sno, would a 1985 Van have TBI or a Quadrajet?
If it has the same ignition system as my '86 K5, the ESC/ECM can be bypassed, remember...
To the OP: Does the ignition module have 4 or 5 pins?
Also, when the key is in the "on" position, do you have 12vdc on the feed coming into the driver's side of the distributor?
~jp
SnoMan wrote:
Ok... you got 12vdc...good.
When you installed the new coil, did you make sure the grounding strap was connected between the frame of the coil and the middle leg of the connector on the side of the cap? If not, it'll smoke your new module in a hurry.
I asked in another response, but I'll ask again...does the module have
4 or 5 pins? If it's a 5-pin module, there's a GM service bulletin that pertains to bypassing the basic ECM that connects to it.~jp
General wrote:
When asking about the module....I assume the black horseshoe item located beneath the rotor. If so...it is a five prong Module, three on one side 2 on the other. So...does this mean I should still be able to get spark?
Go to where the missing box is under the drivers seat, jumper the green wire to the black wire, this bypasses the ESC function. (you'll no longer need the module under the seat, so don't run out and waste any money on one)
A blue scotch-loc will work fine for his.
An 85 G chassis van is not TBI.
Without the ESC/ECM module connected, you probably will not be able to get spark.
The purpose of the ESC (electronic spark control) is to delay (retard) spark timing based on input from a knock sensor. The 5-pin module you have basically has an "in" and an "out", which are pins 1 & 3 on the
3-pin side of the ignition module.Aarcuda69062 gave you the quick fix on how to bypass the ESC. If the ESC is missing altogether, then this is also the solution to get up and running with that 5-pin ignition module. Basically, if you traced them back to the distibutor, the two wires he describes connect to those two outer pins on the ignition module. You're just bypassing the computer and letting it form a loop.
As I stated earlier, that early form of electronic spark control was problematic enough to where GM issued a service bulletin detailing the very simple process of bypassing the system. Once the two wires are jumpered together, the ESC can be disconnected altoghether.
~jp
General wrote:
Better be ready to run timing at ATDC some because it will knock on 87 octane in warm weather big time if it is a ESC system and when you retard spark you retard MPG too.
----------------- TheSnoMan.com
305 were the first with ECS even before they were TBI injected. THe whole theory with ECS was to allow for higher compression with some knock protection. disable it you will have to retard static timing even more to prevent knock and reduce MPG too which it not to wise with today fuel prices.
----------------- TheSnoMan.com
NO SPARK
TIMING CHAIN GEARS Broken ( does the ignition rotor Turn when rolling over the Engine?)
Distributor Gear pin SHEARED
Distributor MODULE ( NEVER CHECK for Spark by grounding an ignition wire. Also Attach a good spark plug to that wire or U will Blow The IGNITION module )
ignition fuse blown in the fuse box ( No 12 volts on the RED wire that hooks to the ignition cap )
J> Without the ESC/ECM module connected, you probably will not be able to > get spark.
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