Engine flatlines/jumps

Quickstop [UK]

Quickstop [UK]

Combating adversyty.
Re: Engine flatlines/jumps

How many times have you pulled the chip out of it? Sounds like a weak connection on one of the conectors at the back maybe?

Why are you using a chip when you have the Ostrich 2.0?
 
nallj92

nallj92

Active member
Re: Engine flatlines/jumps

do you have any RF noise from anything close to the ECM? I had similar issues with running/not running, and came out to be the MSD was too close to the ECM, once unplugged and moved everything runs great. Now I am adding a cap for the MSD and moved it to the engine back instead of in the cab.....
 
qbnkiller

qbnkiller

Conflaguration Specialist
Re: Engine flatlines/jumps

BS3...BS3...BS3...BS3...BS3...BS3...any questions?


Oh yeah...stand-alone wiring harness also!!
 
Beavis

Beavis

Still plays with trucks
Re: Engine flatlines/jumps

qbnkiller said:
BS3...BS3...BS3...BS3...BS3...BS3...any questions?


Oh yeah...stand-alone wiring harness also!!
Click to expand...

I bet thats what he is thinking also at this point. I know i would of done sooner than he this, he has more patients.
 
Quickstop [UK]

Quickstop [UK]

Combating adversyty.
Re: Engine flatlines/jumps

|How much is a BS3 all in? A lot. Code 59 works for most other people, no reason this is different. a $3000 loom is an expensive option! :)

It's an intermittent harness failure - that's what's stopping the ALDL feed - nothing else at this point I think.
 
Aeroking

Aeroking

e.i.
Re: Engine flatlines/jumps

first off, theres no problems with the harness, theres no failures or fractures of the harness.

The truck responds to the stock memcal chip, and doesnt respond to the G1 & chip (or ostrich) combination. So i'm 99.99% sure thats not a harness problem. I'd have to say that it would be a chipset problem. I've used different BINs, so i know my problem isnt a corrupt BIN.

I had someone else mention the locality of the MSD box to the ECM. My MSD box is mounted where the ABS module used to sit. So its pretty far from the ECM (now in glovebox). I will definitely look into adding the capacitor to the MSD to try and isolate electonic noise.

I have started saving for a standalone. :tup:
 
Quickstop [UK]

Quickstop [UK]

Combating adversyty.
Re: Engine flatlines/jumps

I don't understand how many tens, maybe hundreds of us can use the same combo and yet you are certain that it doesn't work for you, or at least certain enough to throw a standalone at it!

It also sounds like the standalones don't have the resolutions of the code59. Regardless, I hope you figure it out.

I still think your harness is dodgy. :)
 
Aeroking

Aeroking

e.i.
Re: Engine flatlines/jumps

i checked the base timing with the tan wire disconnected. I noticed that the engine will go from high idle to low idle back and forth (600rpms, and 1500rpms respectively). At the 600rpm idle my timing mark was right on 0deg. But when the truck went into high idle, the timing make jumped to about 35deg advanced. The timing would change back and forth with the rpms. This was with the MSD 6AL unplugged. Strange.


Also, i bought the MSD noise filter, and installed it right next to the 6AL. I also rerouted my 6AL power wire. Took it off the firewall (close to the engine harness and ECM in glovebox. And routed it along the radiator away from everything.


Any ideas as to what would cause the timing to rise with RPMs, even though the electronic advance is disconnected. I've already changed the igniton module back and forth, and a different cap/rotor with no change in results.

Also, when i was timing the truck, i noticed the misfire. and saw the timing gun cutout for a split second, so i know the miss is in the ignition system. Tonight, i'm gonna check the other plug wires with the timing light to see if they are all cutting out, or just #1 cylinder.

Ignition parts:

MSD Blaster 2 coil, MSD 8mm wires, NGK plugs, billet aluminum distributor, MSD cap/rotor, MSD 6AL box, noise filter, MSD 2step.
 
Aeroking

Aeroking

e.i.
Re: Engine flatlines/jumps

to recap this thread.

- truck wont go over 4800rpms unless i add a ton of timing

- have a split-second misfire, completely random, not systematic

- the truck randomly looses ECM connection. doesnt matter if i use a chip, or Ostrich


Thing i've done to remedy the problems:

- NEW distributor, ign module, cap/rotor, plug wires, plugs
- NEW ECM, G1 adapter, chips, and emulator cable
- hotwired the ECM to the battery
- tried different BIN files
- ran without MSD box
- tried different FPR, went through fuel system
- different alternator, new battery
 
Petesgn

Petesgn

Member
Re: Engine flatlines/jumps

Aeroking said:
to recap this thread.

- truck wont go over 4800rpms unless i add a ton of timing

- have a split-second misfire, completely random, not systematic

- the truck randomly looses ECM connection. doesnt matter if i use a chip, or Ostrich


Thing i've done to remedy the problems:

- NEW distributor, ign module, cap/rotor, plug wires, plugs
- NEW ECM, G1 adapter, chips, and emulator cable
- hotwired the ECM to the battery
- tried different BIN files
- ran without MSD box
- tried different FPR, went through fuel system
- different alternator, new battery
Click to expand...

bad ground to the ecm ?
 
Aeroking

Aeroking

e.i.
Re: Engine flatlines/jumps

high 20s, and even there, the rpms just barely creep past 5000 at WOT.

i just got done ohmming the wires on the distributor signal. I ran continuity on the (C119) 4-pin connector at the ignition module to the ECM. Everything checked out. I worried because i know the wires are tight at that connector.

The only thing left is the pickup coil. It came with the billet distributor, so i'd assume its good. But of course, i cant assume anything. So tomorrow, i'll switch pickup coils on the distributor and see if it makes a difference on the base timing problem. The two-wire jumper harness that runs from the igniton module to the coil is good, i have a couple spares, so i tested and they made no difference.

So something on/in the ignition system (separate from the ECM) is causing the base timing to jump from 0deg to 35deg randomly. :tdown:
 
turbodig

turbodig

Active member
Re: Engine flatlines/jumps

Aeroking said:
So something on/in the ignition system (separate from the ECM) is causing the base timing to jump from 0deg to 35deg randomly. :tdown:
Click to expand...

Curious... how do you know this? Measured, or what the datastream reads?

I'm really wondering what would happen for you if you re-programmed a memcal (or had a socketed memcal) and just used it in the ECM, with the metal cover on.

Interestingly enough, have a local Sy that just got running after a long-term engine rebuild. It seems to want more timing than normal, also. I suspect the balancer, and we've got one on the way to test that.

Where does your #1 plug wire sit on the distributor, in relation to the back of the manifold? Where does the connectors on the distributor point when the dissy is timed right? (assume 12 o-clock is straight towards the firewall)
 
Aeroking

Aeroking

e.i.
Re: Engine flatlines/jumps

turbodig said:
Curious... how do you know this? Measured, or what the datastream reads?

I'm really wondering what would happen for you if you re-programmed a memcal (or had a socketed memcal) and just used it in the ECM, with the metal cover on.

Interestingly enough, have a local Sy that just got running after a long-term engine rebuild. It seems to want more timing than normal, also. I suspect the balancer, and we've got one on the way to test that.

Where does your #1 plug wire sit on the distributor, in relation to the back of the manifold? Where does the connectors on the distributor point when the dissy is timed right? (assume 12 o-clock is straight towards the firewall)
Click to expand...

i had the timing light set for 0deg, and shot the balancer mark, then when the mark moved, i adjusted the timing light to about 35deg to bring the mark to the pointer.

If the firewall is 12 o'clock, then #1 spot on the cap is 6 o'clock. The ignition module connections are at 2 o'clock
 
Aeroking

Aeroking

e.i.
Re: Engine flatlines/jumps

IIRC, the 4pin connection on the ign module is the bypass, the EST, and the signal. so if i disconnect that connection and try to run the truck, it should run on the base timing, correct? The truck would run straight from the coil to the distributor. That would factor out the ignition module, the pickup coil, and the ECM harness.
 
turbodig

turbodig

Active member
Re: Engine flatlines/jumps

Aeroking said:
i had the timing light set for 0deg, and shot the balancer mark, then when the mark moved, i adjusted the timing light to about 35deg to bring the mark to the pointer.
Click to expand...

This is with the brown wire unplugged, I take it?

This would point to the pickup, or the module. Or possibly, some really ugly crossfire. You'd see that in the cap.

How long does it stay when it "jumps"? Does it jump back? Does it follow engine RPM or anything?

Try this - pull the plug on your alternator and see if the jumping still happens.
 
turbodig

turbodig

Active member
Re: Engine flatlines/jumps

Aeroking said:
IIRC, the 4pin connection on the ign module is the bypass, the EST, and the signal. so if i disconnect that connection and try to run the truck, it should run on the base timing, correct? The truck would run straight from the coil to the distributor. That would factor out the ignition module, the pickup coil, and the ECM harness.
Click to expand...

The module needs the pickup even in bypass mode... the pickup is effectively the "points" of the deal.
 
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