Cascade Crew

Xophertony

so i am driving to my dads (where i am now) and my white 1986 2.8 does the oddest thing, the engine surges (as if it just threw it momentarily shut off and then started back up again) and my tach dropped to zero. the engine stayed running after that hickup and will restart and run smoothly. however the tach no longer works, and if i turn the lights on it does the "your lights are on when engine is off" ding. did my ECM just go? am i running in failsoft or limp home modes? did my ignition module go?(it controlls the tach, and it's integraty has been called into question as of late) will the car run without that?

where to i even start to diagnose this?

i figured the first thing to do was open the hood and look for that plug that comes loose in the movies and causes the hero's car to fail at exactly the wrong moment. no such luck. i did however find that a long unused connector for somthing had melted to my exhaust manifold, possably causing a short to ground. it was a red wire, but i have no idea what fuse to check.

i am now going to go into the garage and hopefully finish up the brakes on the GTA so i can drive to work tonight.... hopefully the 86 is not out of it for dyno.

i need some ideas guys. i am going to look for ECM codes later, but one thing at a time, first things first i am fixing the GTA. i'll check back later.....

Jess · Posted: Mon Jan 22, 2007 3:44 pm Post subject:

When the ignition module went out in my 89 2.8 the car would not start at all. So I would rule that out. No other idea's sorry man...

Xophertony · Posted: Mon Jan 22, 2007 3:56 pm Post subject:

thanks jess. knowing what is NOT broken helps in finding what is broken.

i got the GTAs brakes all bled and good to go. so i will be driving that for the rest of the day. tomorow after chris and i hit the yards i'll see about tinkering with it and pulling any engine codes i can. i have this nasty feeling that i fried the ECM by shorting that connector to ground...... man would that suck. atleast there are no shortage of MPFI cars in the yards to pull parts from Very Happy

i fear i may be out of dyno v6 wise though. GTA will be there Yup yup

hopefully this turns out to be a fuse or melted wire or somthing easy like that. Smile

chevymad · Posted: Mon Jan 22, 2007 7:53 pm Post subject:

Don't be so quick to rule out the module. As Jess says it normally fails with a no start. But there's always exceptions to the rule. Just first impressions, I was thinking module or maybe a wire splice in the tach signal wire. It's possible part of the ecm timing out of the module is bad. Or as you say the ecm itself. Just an idea, throw a timing light on it. See if the timing is the same with/without the check connector hooked up. If it doesnt change you have a problem in the timing control(ecm, module, possible wiring). If it does change all that is working. Then it could be the wiring where it splices off to the dash possibly. Or maybe the ecm. It's even possible its the dash itself.

Twilightoptics · Posted: Tue Jan 23, 2007 12:08 am Post subject:

I had the same thing happen although different setup...

Had a crane optical points setup on the S10. Without the ballast resistor it would heat up and thermal shutdown just for a split second EXACTLY like you speak of.

Do what Brandon says!

Xophertony · Posted: Tue Jan 23, 2007 1:17 am Post subject:

sounds like i have a plan of action now.

step one:
check ECM fuses.

step two:
put timing light on it and check timing with and without EST connector.

Step three:
use paperclip to see if ECM is functioning (it gives code 12) and see if any other codes pop up.

step four:
depends on results of steps 2/3

QUESTION:
when the engine was rebuilt by PO i am mostly sure the original dizzy went back on. if it is indeed my Ignition module should i just replace the whole dizzy with one of those MSD or Crane ones that include their own (better i assume) ignition module, or just replace the ignition module? i would like to keep this car running as cheap as possable, but i also don't want to have to spend more money later casue i shortcutted this time. so i guess it boils down to this: what is the service life on a distributor?

Twilightoptics · Posted: Tue Jan 23, 2007 8:08 am Post subject:

"I'd just run a quality module. Maybe a GM part.

The billet distributors IMO don't offer much if any advantage over an OE piece, maybe they aren't as good in some ways.

I run a Holley billet HEI piece with a "performance" module that they used to offer (with a CD box I put in when I used to run nitrous). But I'd run a factory HEI with a good module that was in good shape as well at moderate (6500 or so) RPM. If I was turning 7500 I'd start to look at a crank trigger. "

-Doug F (Holley Commander 950 engineer)

Xophertony · Posted: Tue Jan 23, 2007 9:19 am Post subject:

thanks paul.

Xophertony · Posted: Wed Jan 24, 2007 4:23 pm Post subject:

wow.... you guys ready for this one.....? it was the guage cluster fuse. Laughing

BTW i could have sworn i allredy checked it, turns out i checked the one above it. Rolling Eyes

so this time it was a real 5 cent fix.

Schultzy89GTA · Posted: Wed Jan 24, 2007 5:16 pm Post subject:

hehe - I have had a few of those type fixes. I'll take a little embarrassment over the high dollar invasive fixes anyday!

Glad you got it did.

-Schultzy

Al Hasse · Posted: Wed Jan 24, 2007 8:07 pm Post subject:

Xophertony · Posted: Wed Jan 24, 2007 8:29 pm Post subject:

Quasi-Traction · Posted: Thu Jan 25, 2007 5:56 am Post subject:

schaweet!!

Does this mean I'll be driving the white bird to dyno for you?

Twilightoptics · Posted: Thu Jan 25, 2007 8:46 am Post subject:

Xophertony · Posted: Thu Jan 25, 2007 12:23 pm Post subject:

DYNO IT!!!!!!!!!!!!!!!!

otherwise i supose you can have the white birdie.

Dewey316 · Posted: Thu Jan 25, 2007 12:35 pm Post subject:

DYNO IT!!!

We are actualy short on numbers right now, with some people dropping out. I'm drumming up a few extra's, but chris, bring the berlie!!! If it breaks down, we can fix it on the side of the road, no worries.

Quasi-Traction · Posted: Thu Jan 25, 2007 1:36 pm Post subject:

I dunno....If the weather conditions are right and someone can help me bleed the clutch enough before Saturday...I can keep my eye on the fluid level and keep topping it off when it gets down there.

I also don't know how bad that fuel leak will be under load. I'll have to do a few short trips to find out.

Its definately not going on the rollers, but it may make a cameo.