No injector pulse

[corvette66]

Hey guys,

I know this is a really common problem but everyone seems to have different problems occuring causing this NO pulse situation. So my question is.. how do you manually pulse the injectors to test them? I have heard of people doing this in the past. My setup is from a 1986 camaro 305.

I have spark and i have fuel pressure. I have also heard that the pickup coil can cause these problems but if the pickup coil was bad would I still have spark? Or the igniton control module. So the pickup coil or ICM is what signals the injector to pulse? Just seems to me that if one of these were bad there would be no spark. Also should I be able to see the fuel spray from the injector? cause I have the fuel rail upside down on the intake so i can see if they spray.

It will run if I spray fuel into the TB. Not very good but it runs. Also this is not a system I have ever used before, I recently got it from an 86 camaro. It's going onto a 4x4 for now.

People also say to check the injector grounds as they go to the ECM. Sure they do go to the ECM but what do I check? The grounds coming out of the ECM? ALL my grounds are hooked up.

Heres another issue. My distributor is the small remote coil style. I thought this coil was only on 87' and newer TPI cars? It couldnt have been swaped because the harness has the 4 prong connector for the distributor. Is this more than likely an 87 harness?

thanx guys

 

[vetteoz]

how do you manually pulse the injectors to test them?

Not aware that you can.
Usual test is to use a noid light to indicate injector pulses from the ECM.
If light flashes OK , then safe to assume the injector is bad if it doesn't spray

I have spark and i have fuel pressure.

What ECM and memcal?

Have you taken care of VATS?

Is TPS set correctly?
Too high a TPS reading while cranking and the ECM will think the throttle is open to clear a flooded engine
so it will shut off injectors

Have you checked inj resistance?

Checked inj fuses ( x2 )

Checked for 12V on one side of inj plug on harness and for open circuit ( not to ground ) on other pin with key off?

Heres another issue. My distributor is the small remote coil style. I thought this coil was only on 87' and newer TPI cars? It couldnt have been swaped because the harness has the 4 prong connector for the distributor. Is this more than likely an 87 harness?

Won't make any difference so long as you have the correct connection from harness to 4 pin dist plug .
The wires are the same ; just connection different between coil in cap HEI and the small cap / remote coil dists

 

[corvette66]

No I did not yet check the resistance of the injectors. But I have 2 sets of them and with the injectors stil in the engine I plugged another (loose) injector into the harness and still got nothing. Who sells a noid light? and do I check the ECM with it or the injectors? Not sure how they work, never seen one.

As for the distributor... your saying the wires are the same so I could splice out the 4 prong plug and wire in an old HEI in-cap style? I have seen threads where people argued that it was difficult to do.

If this can be done, how so? My 4 prong connector has the following wires: Black with red stripe, white, Tan with black stripe, Purple with white stripe. All 4 go to the ECM. The large HEI that I have has the typical three wire plug brown, black, pink, and the single red BAT and the Black TACH wires. How would these be spliced?

thanx

 

[corvette66]

oh also, do you know what the ohms should read for a pickup coil in the small remote coil distributors? Does 800 sound abot right?

 

[vetteoz]

As for the distributor... your saying the wires are the same so I could splice out the 4 prong plug and wire in an old HEI in-cap style?
If this can be done, how so?
My 4 prong connector has the following wires:
Black with red stripe, white, Tan with black stripe, Purple with white stripe.
All 4 go to the ECM.
The large HEI that I have has the typical three wire plug brown, black, pink, and the single red BAT and the Black TACH wires.
How would these be spliced?

All HEI's have the three wires from base to cap and the 12V BATT / TACH terminals on cap
Swap only works with a computer controlled HEI ( all TPI Vettes and early F-Body TPI ) that has a large 4 pin plug from the base with same color wires as on the plug that connects to small cap version.
Reg HEI won't work because it has mech / vac advance

Who sells a noid light?

http://www.cadillacforums.com/forum...question-regarding-noid-light.html#post259360
NOID Light can be hired from auto parts shops apparently.

do I check the ECM with it or the injectors? Not sure how they work, never seen one.

Light plugs into a injector harness plug ( in place of injector )
and will flash if any inj pulses from the ECM are seen when engine cranking over

http://www.ehow.com/how_4453009_test-voltage-fuel-injectors-noid.html

 

[vetteoz]

A read
Ohm's Law - It Really Works!

 

[corvette66]

"ohms law" that was an informative read, thanx

so here's a question... If I swap the Ignition control module, does it matter if it's from a 305 or 350? It should function just the same right?