84 w/CF won't start

[vigman]

Further Info

The TB that has 5 VAC connections
( The Front one)

#1 Connection( the large one for PCV valve)

#2 EGR MANIFOLD VACUUM
( next to the PCV large connection)

#3 The MIDDLE small connection is
"AIR CLEANER MANIFOLD VACUUM"
to the right ( looking at back )

#4 The TOP one ( with a tweek in it )
is PORTED vac for the canister purge.
(I think that's the one you want for syncro )

#5 The one by the throttle screw
MAP sensor manifold vaccum.

So it really dosent matter where you pick up vac to run certian stuff.. but it DOES matter if the function of the port is above or below throttle plates.

Vig!

 

[kmcewan]

All unused vacuume Ports Plugged

I'm thinking now that I screwed up the throttle linkage adjustment.

I've got to reread the instructions again.

If I'm correct, the throttle linkage should be completely out of the picture when the TBs are adjusted. I'm not sure now that this was the case when I adjusted them.

I'm not sure how to do that now.

Ken

 

[kmcewan]

TBs balanced

Vigman,

Front TB was drawing to much VAC as you suscpected.

Checked it with my vac gauge. The rear barely moved the needle, and the front registered over 10 ". Adjusted the front TB until it read the same as the rear on the VAC gauge, then attached the mannometer and adjusted the front to 6".

Both are balanced, but now it's not running as smooth as it did before. Took it out for a road test and it stumbles if I give it throttle too fast. If I apply throttle slowly, no problem.

I guess it's back to checking timing and checking for codes.

Ken

Oh, by the way... I checked the Air cleaner and the flaps are open with no vacuume applied.

 

[vigman]

Flaps

You need to have em CLOSED until you rev and the flaps OPEN as the manifold vac reduces.

BUT if your not hooked UP to any vac they SHOULD be open.

I have a funny feeling that ( Based on our IM earlier) that the rear should lead the front by a few inches of VAC ( Hence the adjustment of the idle stop screws)


I would try to hook the Air cleaner up so the flaps work as described.. it might be a tad lean when you ROMP on it... hence the bogging.

AND
I would invest in a better coil... made a BIG difference in mine.


Vig!

 

[vigman]

Static settings

the FRONT needs an additional 1/4 turn after contact.

The rear needs 1/2....

Hence I think the rear needs to lead ( by 2 or so inches of VAC.


AND you need to disconnect the battery to clear the ECM and UNLEARN the BAD and re input the NEW..

Drive it for a bit after adjustments so the IAC's can shut and the ECM can re learn.


Vig!

PS dont forget the 10 second shutdown rule!

 

[kmcewan]

84 CF won't start?????

Vigman,

Remember this subject in the first thread?

After disconnecting the battery, the injectors aren't pumping gas anymore.

All I did was disconnect the battery for one minute to allow the ecm to unlearn.

When I reconnected it, the motor turns over but no fuel is coming out of the injectors.

I can hear the fuel pump when the ignition is on and I'm measuring around 11.9 v between injector leads.

Could powering down the ECM have done this?

Help!

Ken

 

[vigman]

Was the key ON

When the Batt was pulled?

Try starting with the pedal 1/2 way down.

This is NOT good news!


Vig!

 

[kmcewan]

Key was off when the battery was pulled.

No fuel coming out of the injectors.

Ken

 

[vigman]

Do the Injectors get a PULSE?

Pull the wire on top of the injector and hook a test light up to it... crank the car.. does the light FLASH...or Strobe?

If YES... you MIGHT have no fuel being delivered... check you fuel pressure... also check the INJ fuses in the panel.


Sumtin fishy here!

Vig!

( Any Error codes??)

 

[kmcewan]

sumtin fishy

I'll check for ingition pulses this evening and also check for fuses.

I hope that is all it is.

After thinking about the sequence of events last night, I can't say for certain that the ingition wasn't on. I'm pretty sure it wasn't though.

What would that do if it was on? Blow a fuse? Blow the ECM?

Ken

 

[kmcewan]

Error Codes.....

I hooked up my scanner last night, and when I tried to scan for codes, the scanner said the computer wasn't responding.

I looked at the ALCL connector, and it looks like the previous owner might have done a hack job on it too.

Ken

 

[vigman]

OH NOOO!!!!!!!!!

Well what chunk of info can I provide now?

BTW

I have 2 84 computers.
#1) works fine but the check engine light drive transistor is blown

#2) Is perfect.


Problem
I forgot which is which.

The one with the blown light still scans good though.

Vig!

 

[vigman]

Or the ECM

Isnt getting power....

Jump A&B and see if the check engine light goes on... If it does... the ECM is powered.

It has to make an ACTIVE ground to light the light.


If you spray quick start down the hole of the TBI does it sputter?


Vig!

 

[vigman]

To answer your question

If the KEY was on there's a good chance that the ECM is toast!


Vig!

 

[Twin_Turbo]

Re: 84 CF won't start?????

Vigman,

Remember this subject in the first thread?

After disconnecting the battery, the injectors aren't pumping gas anymore.

All I did was disconnect the battery for one minute to allow the ecm to unlearn.

When I reconnected it, the motor turns over but no fuel is coming out of the injectors.

I can hear the fuel pump when the ignition is on and I'm measuring around 11.9 v between injector leads.

Could powering down the ECM have done this?

Help!

Ken

Injectors aren't controleld by voltage but by short to ground!

 

[Twin_Turbo]

W/ Key on you may have fried the ECM but it's not that likely.

If you jumper tha ALDL does the CEL come on?

 

[vigman]

Twinnie

The Injectors ARE controlled by an active ground.... BUT the ECM provides the ground electonically.... No power to the ECM... no switched ground.


So.... either

The ECM is TOAST... but that can be checked by putting the test light across the 2 pin connector going to the TBI injector ( the HOT line is ALWAYS HOT)

and the test light has to PULSE... not stay on all the time!


OR

The fuel is NOT getting to the TBI assys...



More info is needed cuz my Ouiji board is out of batteries!


Vig!

 

[Twin_Turbo]

That's what I said, controlled by switch to ground. I mean that as to 11,9V measurement is USELESS to determine if ECM is functioning correctly.

Doesthe fuel pump keep running?

Marck

 

[kmcewan]

Crap

ECM is toast.

Followed the diagnostics in the service manual.

Test light stayed on during cranking.

Shorting PINs A & B on the ALDL did nothing. No check engine light.

Fuses were all ok.

Resistance between terminals was greater than 1.4 Ohms.

All points to faulty ECM.

I guess I'll place an order for an ECM tomorrow.

Mid America sells them for about $100. Anyone else have a suggestion on where to buy?

Ken

 

[vigman]

Well

I would give you mine... but I couldn't get it to you faster than Mid America could..... remember... swap the PROM ( Chip ).... and take you time doing it!


Tough break.....


Vig!