New version(?) of Vette won't start problem

[vigman]

Area's fed from Link H

Always HOT from Battery
Orange wires

Oil pressure switch
Fuel pump relay
Mass burnoff relay
Mass burnoff CONTROL relay

ECM DIRECT 2 places
Connector C2 ( pin B1) Orange
Connector C1 ( pin C16) Orange

All these connection points need batt + all the time... that's what I ment... Sorry


Vig!

 

[Tuck]

Vigman-thanks for taking the time to help me out on this-hope to be able to pass on what I learn to others in the future.

"DO you have a big cluster of wires that junction to a black plastic cage by the battery near firewall?"

Yes I found the big cluster on the passenger side of the battery going in to the firewall. I also beleive the MAF sensor power relay & burn off relay are right behind the battery. I

 

[vigman]

If the ECM dosent have power

I do not think you will get spark.

If no check engine light... no timing to the distrib via ECM.

So I'm still thinking you have a MAIN power feed problem.

Vig!

 

[vigman]

The big cluster

Stick a test light in there... is it HOT?

That's fusible link central!!!!! Bingo..

Then IF you have a sharp probe check AFTER the link splice on the actual wire to see if it's HOT... there SHOULD be about 7 lines there!!!!


Vig!

 

[vigman]

And your welcome

Always glad to lend a hand to a fellow CAC member... reguardless how SHORT they may be..

( Get it SHORT...hahahaha oh sorry)

I like to have an OPEN series of dialouge

( AHhhhh he did it again....)

Engineers...Jeeze!



Vig!

 

[Tuck]

"Stick a test light in there... is it HOT?
That's fusible link central!!!!! Bingo..
Then IF you have a sharp probe check AFTER the link splice on the actual wire to see if it's HOT... there SHOULD be about 7 lines there!!!!"

Sorry I don't have a test light (got one at work-little good that does right now) - I have been using a multimeter up til now. I can run and get one at the Pep boys down the street if you think it will help. If not, what do you need me to check with the multimeter?

Also, found the fan switch you refered to-I grounded it out and the fan fired right up so I think that means H is good.

 

[vigman]

Ok good

Well you can use your multimeter
But for this stuff I like a GOOD test light.. not the 2.00 POS

 

[vigman]

Tuck

Do you have AOL instant messaging?

 

[Tuck]

Looks like the sight was down. I don't have AOL Instant messenger. I do have MSN messenger (darrelltucker @msn.com) & yahoo messenger (tdarrell3@yahoo.com) if that will work.

Also, one new iem that may be of interest: I had to pull the ECM back out-I was trying to get it back in before dinner and forgot to put the eprom cover back on ooops! Anyway, I noticed that the ECM was very warm-not hand burning warm but a lot hotter than I thought normal considering the motor has not ran in a couple of days and I only had the ignition off and on occasionally conducting testing.

 

[vigman]

They do run a TAD hot!

Try touching it after it's been under the dash... during a So Cal summer! YIKES!!!!!

But even if the Eprom was toasted the ECM would clock an error code 51.....

AND I'll bet that the 2 pins I called out on the ECM ( Orange ) Are NOT hot.

Main power feed problem.....


... that's my final answer!

You will be on you own for the better part of today ( Have to work yeech)

The Haynes book has a Good schematic but BUY A MAGNIFER... you WILL go blind reading that one. Or have Ken scan his factory shop manual 1 page for the Multi port injection block diagram and 1 page for power distribution.

AND

Fusible link 101
From the Lug you have about a 2" piece of wire going to the Black moulded thing.... the "Wire" coming out of the black moulded thing is the "LINK"... that's the fuse if you will.... the SPLICE is the connection point back to REAL wire... make sure the actual WIRE has power.

Vig!

 

[Tuck]

ECM Power

Vigman.

I do have power (12+ volts) to both Orange wires going in to the ECM (with key off). I just checked it but also now that I think about it- I don't think it would be getting warm like I mentioned yesterday without power.

I think I just shot a hole in your theory-but maybe this will help you narrow it down.

 

[vigman]

Power & Check engine crkt

Ok...

Well then yes you are correct...however we must check everything so were not shooting in the dark......

And shooting holes in theories is the correct way to do things... the more holes..the less places to check.. and since I don't have your car in front of me... YOU have to be my input device.

What happens when you jump pins A&B on the ALDL connector?( Betting nothing )

So

Crank... but no fire...

Power to the headlights & Motors

Power to the pump relay

ECM fuse & Inj fuses good

No spark

No check engine light on key ON

AND you say C-16 & B-1 are HOT

That's where we are currently at right?

Next steps

Make sure ECM pin A-12 is grounded
( check with OHM meter)

Check ECM if pin A-6 Pink/Black is HOT with the KEY ON! If yes...proceed. If NO your ECM fuse is toast OR the power feed to the panel is bad.....

There is a 15 way connector ( Pin R ) under the dash CLOSE to the ECM which the A-6 pin routes thru.

Next

( Disconnect battery first)

Remove the ECM connectors

Find ECM PIN A-5 ( Brown / White ) and Ground this pin.. reconnect battery... turn key on

Does the light light?

That means the BULB is good & you have a good power feed on the Inj 1 circut.

The BAD news is the ECM is probably toast
IF all the above is true.

Pin A-5 is the output of the ECM that flashes the check engine light by grounding that line.

PHEW!


Vig!

 

[Tuck]

Vigman,

Your current status is all correct.

New checks:
Checked A-12: it is grounded (8 ohms). Also, while I was at it I checked the other power ground (D1) which is also good.

Checked A-6: it is hot with the key on. Also followed the Pink/black wire to the other connector-it is hot there also.

I grounded A-5 but the light did not come on. I know for sure it was grounded because I used the continuity check on my mulitmeter to ground it. When I turned the key on it gave me the beeeeeeep! that there was connectivity to ground.

I pulled the dash apart earlier and checked the bulb and I am pretty sure it is good (I can check it again but considering the other issues -the light not coming on is still part of the problem and probably not the bulb.)

I found an ECM locally for $114 but won't be able to get it until I return from the east coast next Friday.

My B-I-L seemed to beleive it was an ignition switch issue. What are your thoughts on that? Anyway to verify yes or no on the ignition switch?

 

[vigman]

You have to HARD ground that line

To check the bulb... don't read thru the meter!

As far as the Ign switch is concerned I have yet to see one fail personally.

You sure about this one?

When you jump pins A & B on the ALDL (for an 86)- I think that puts you in to the Diagnostic mode to check trouble codes. I don't remember the fan coming on. Am I confused?


Yes ... the fan comes on!



Vig!

 

[Tuck]

Latest info

Vigman,
Ok I have completed the tests we duscussed during our IM session:

First reference my multimeter-it is a Fluke Model 77. Had it about 10 years-never calibrated. I can double check the 8 ohm reading when I return with another meter.

Ok conducted testing on the DIC:
First verified bulb & socket for CE (not SES lol!) light was good. Switched it with E-brake set. Both worked for e-brake, neither worked for CE. Flex pad looked in good shape.

I do have 12 v to the hot side of the bulb with key on and A5 on ECM grounded. BUT I do not (repeat do not) have continuity from ground side of light to A5 of ECM. Also do not have continuity from Pin 12 ( Brown & white wire) to A5. I am thinking this might be the best clue so far-but I am not sure what it means-hoping you will. I did notice with key off I had good chassis ground connectivity from Pin 12 and ground side of light.

I also completed the "fake ECM" test . It seem to work well other than it was no help-it kept repeating code 12. Not surprising since I have had the battery disconnected 50 plus times over last few days. I will confirm 12 code with test light on friday.

I will await your much appreciated guidance-thanks again for all your help. I think we are getting close!

Tuck

 

[vigman]

Ah SO!

So we must trace the Brown white wire thru the harness.

You would have a Code 12 all the time since we removed the battery... and that CLEARS the codes.


If you try to start... what happens?????


And since you do have a code 12 (meaning no problems) your ECM is ALIVE!


Now to find the pope's in the Pizza!

Will dig tonight.


Vig!

 

[Tuck]

Back in town

I am ready to go at this again when you have time.

FYI I got a trouble light but before I could verify the ECM codes with it -I jumped A & B on the ALDL and the SES light (yes SES-I was wrong about CE) came on when I turned the key on. Not sure what the deal is-must have had something to do with pulling the dash apart but I swear I checked it after that and it did not work.

Anyway, now I can read trouble codes like I am supposed to BUT the code is 12 which does not help the bigger problem.

It does appear that the ECM has been ruled out (I think) now I am going back to the ignition.

Could this be a VATS problem? I have seen some of the posts on VATS problems and it appears to be similar to what I have-no spark, no injectors, fuel pump. etc. The only thing that was not clear was-if the VATS system is screwed up will the car still crank-but not start or will it even crank at all?

 

[vigman]

Inverted

If the VATS in your year TRIPS you should get a NO Crank condition...

Fuel/ Ign etc should be alive.

So with a 12 ( Error code ) try starting..... It should give you a code NOW if there is a NO start condition.

I'll check with you later...

Any other stuff about the car that we should know?


I'm still puzzled by this


Vig!

 

[vigman]

Let's Review

With the Ign ON

You have POWER to the BATT line on the Distrib.

With the Key OFF

You have POWER to the Fuel pump Switch ( Orange line )


Check the connections at the distrib rear... 4 pin connector hanging twds firewall.

Check the connections @ the EST module ( The 5 pin deal on the AC blower cage just over the windsheild rez.)

And read my previous postings on VATS......

I still think the car was fine...UNTIL you did that work on the fusible links....

MY GUT HUNCH we are still missing a POWER FEED somewhere.


Vig!

 

[Tuck]

Info request

Vigman,
No trouble code other than 12.

Yes with key on I have power to BAT lead on distrib
With Key off have power to Orange lead on fuel pump relay.

Checked 4-wire connection behind distrib-saw now problems.
(Not sure what else to check other than visible connection)

Instead of EST do you mean ESC module? I checked connections on ESC module which is bolted to the passenger side of blower cage-I think that is what you meant. It is connected-can not find wiring info to make more detailed check.