Fuel injector testing 1985 4 plus 3
Thread Starter
Drifting
Joined: Feb 2013
Posts: 1,462
Likes: 48
Fuel injector testing 1985 4 plus 3
Hello,
So I think that my FI are not firing. I made a noid with a 194 bulb. Plugged leads into the connector and cranked the engine. I did not see a pulse. But, when I touched one wire to ground I heard the FI solenoid move. The ECM is new the PROM is new. The connector wires have 12 volts. What do I do next.
Thank you
So I think that my FI are not firing. I made a noid with a 194 bulb. Plugged leads into the connector and cranked the engine. I did not see a pulse. But, when I touched one wire to ground I heard the FI solenoid move. The ECM is new the PROM is new. The connector wires have 12 volts. What do I do next.
Thank you
Melting Slicks
Joined: May 2014
Posts: 2,892
Likes: 592
From: New Port Richey FL
I am not saying your 194 test light will not work but I think the voltage properties are much higher and would make it lazy or weak. You can get a loan a tool Noid light from most large parts store
I take it you're car won't start, so the basic questions, spark? Fuel pressure?
I take it you're car won't start, so the basic questions, spark? Fuel pressure?
Last edited by s carter; Oct 19, 2019 at 03:29 PM.
Thread Starter
Drifting
Joined: Feb 2013
Posts: 1,462
Likes: 48
Thank you for the help. First thing is you are correct about the bulb. I thought it would light. On YouTube the bulb is barely visible. So I need to try again and be aware that the bulb doesn't get bright.
The gas is fresh and I have no reason to believe that water is in the tank.
We have spark. Verified by timing light
ECM and PROM are new.
Thank you again
The gas is fresh and I have no reason to believe that water is in the tank.
We have spark. Verified by timing light
ECM and PROM are new.
Thank you again
Melting Slicks
Joined: May 2014
Posts: 2,892
Likes: 592
From: New Port Richey FL
OK Guam that makes things tougher. On hand in the Middle of the Ocean for the Noid light see if you can find a 12 +- volt LED (low volt LED Christmas Light) or a junk Computer or some kind electronic.
Odds are there are Noid lights on Guam. other cars have Bosch Injectors BMW, Mercedes and probably many others
Odds are there are Noid lights on Guam. other cars have Bosch Injectors BMW, Mercedes and probably many others
Melting Slicks
Joined: May 2014
Posts: 2,892
Likes: 592
From: New Port Richey FL
I know things there are much more expensive and Mainland mail is probably slow, but on ebay the Noid you need is $7.00 and fits in a padded Envelope and whether it comes from a U.S. or Asian, Australian Market.
Did the car run before Prom/ECM replacement.
And the main Question now 35 psi. and in the Absence of a pressure Gauge. When Key is Cycled on (Not Cranking)do you hear the Fuel Pump Cycle for a second or two. and if you go to the Fuel test port and push the Pin does Fuel Spray?
Did the car run before Prom/ECM replacement.
And the main Question now 35 psi. and in the Absence of a pressure Gauge. When Key is Cycled on (Not Cranking)do you hear the Fuel Pump Cycle for a second or two. and if you go to the Fuel test port and push the Pin does Fuel Spray?
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Thread Starter
Drifting
Joined: Feb 2013
Posts: 1,462
Likes: 48
I know things there are much more expensive and Mainland mail is probably slow, but on ebay the Noid you need is $7.00 and fits in a padded Envelope and whether it comes from a U.S. or Asian, Australian Market. Some sellers will not mail it to Guam. But, I did make a noid from an LED light. The injector is being pulsed
Did the car run before Prom/ECM replacement. It ran with the original ECM bad idle but it ran for a while and the plugs where black. And it ran with this one for a few seconds. I replaced the cap and rotor. Dropped in the distributor. Hit the key and it fired up.
And the main Question now 35 psi. and in the Absence of a pressure Gauge. When Key is Cycled on (Not Cranking)do you hear the Fuel Pump Cycle for a second or two. and if you go to the Fuel test port and push the Pin does Fuel Spray? I am getting fuel pressure. We measured up to 40 psi. The cold start injector was feeding so much fuel that I had to change the oil. I disconnected it.
One problem I am having is the battery is not turning the car fast enough. I am resolving that issue this week.
thank you for the help
Did the car run before Prom/ECM replacement. It ran with the original ECM bad idle but it ran for a while and the plugs where black. And it ran with this one for a few seconds. I replaced the cap and rotor. Dropped in the distributor. Hit the key and it fired up.
And the main Question now 35 psi. and in the Absence of a pressure Gauge. When Key is Cycled on (Not Cranking)do you hear the Fuel Pump Cycle for a second or two. and if you go to the Fuel test port and push the Pin does Fuel Spray? I am getting fuel pressure. We measured up to 40 psi. The cold start injector was feeding so much fuel that I had to change the oil. I disconnected it.
One problem I am having is the battery is not turning the car fast enough. I am resolving that issue this week.
thank you for the help
Melting Slicks
Joined: May 2014
Posts: 2,892
Likes: 592
From: New Port Richey FL
Well at least we now know we have Fuel Pressure, Spark, it sounds like Fuel is washing into the Crank so fuel is hitting the cylinders.(or going thru bad Fuel pressure Reg.)
Now is the Distributor in close to Timing. Top of Compression Stroke Cylinder 1.
also How is the Fuel I Know you had mentioned its fresh gas but Guam is not known for their Drought Conditions and I have seen lots of water in fuel in a lot drier locations. So a little draw off from bottom of tank doesn't cost and rules out water.
Since you have Injector Pulse & Spark the ICM is probably OK
Now is the Distributor in close to Timing. Top of Compression Stroke Cylinder 1.
also How is the Fuel I Know you had mentioned its fresh gas but Guam is not known for their Drought Conditions and I have seen lots of water in fuel in a lot drier locations. So a little draw off from bottom of tank doesn't cost and rules out water.
Since you have Injector Pulse & Spark the ICM is probably OK
Thread Starter
Drifting
Joined: Feb 2013
Posts: 1,462
Likes: 48
Well at least we now know we have Fuel Pressure, Spark, it sounds like Fuel is washing into the Crank so fuel is hitting the cylinders.(or going thru bad Fuel pressure Reg.)
I have a new regulator on it
Now is the Distributor in close to Timing. Top of Compression Stroke Cylinder 1. I set the timing and I believe it is correct. Like I said after I put the new cap and rotor. It fired right up.
also How is the Fuel I Know you had mentioned its fresh gas but Guam is not known for their Drought Conditions and I have seen lots of water in fuel in a lot drier locations. So a little draw off from bottom of tank doesn't cost and rules out water.
Fuel is new. It has been consuming so much because of the flooding.
I think it needs a new battery. This one is barely turning the engine. So this weekend we see what we need to do about that.
Thank you
Since you have Injector Pulse & Spark the ICM is probably OK
I have a new regulator on it
Now is the Distributor in close to Timing. Top of Compression Stroke Cylinder 1. I set the timing and I believe it is correct. Like I said after I put the new cap and rotor. It fired right up.
also How is the Fuel I Know you had mentioned its fresh gas but Guam is not known for their Drought Conditions and I have seen lots of water in fuel in a lot drier locations. So a little draw off from bottom of tank doesn't cost and rules out water.
Fuel is new. It has been consuming so much because of the flooding.
I think it needs a new battery. This one is barely turning the engine. So this weekend we see what we need to do about that.
Thank you
Since you have Injector Pulse & Spark the ICM is probably OK
Safety Car
Joined: Aug 2009
Posts: 3,751
Likes: 276
From: Melbourne, Victoria, Australia
Remember the injector has 12 volts with ignition on, but the ground goes via the ecm (does the ecm have a good ground connection). is it the correct ecm did you pull the chips from your old ecm and put them in the new ecm??? Reco ecm,s come without the chip.
The injectors batch fire all left then all right via ecm pulse width.
see link below Post 5 has a injector wiring diagram
https://www.corvetteforum.com/forums...-into-one.html
The injectors batch fire all left then all right via ecm pulse width.
see link below Post 5 has a injector wiring diagram
https://www.corvetteforum.com/forums...-into-one.html
Last edited by gerardvg; Oct 21, 2019 at 08:03 AM.
Melting Slicks
Joined: May 2014
Posts: 2,892
Likes: 592
From: New Port Richey FL
If you remove the coil cover and look in do you have a set of Spades in the center of where the Wires plug in, this should fill the center spot. You should have a Spade for each wire in the coil Harness in car. if your coil happens to have a wire pre-connected to it Great you have a Spade for every wire.
https://www.oreillyauto.com/detail/b.../5801753?pos=2
https://www.oreillyauto.com/detail/b.../5801753?pos=2
Last edited by s carter; Oct 21, 2019 at 09:24 AM.
Thread Starter
Drifting
Joined: Feb 2013
Posts: 1,462
Likes: 48
Remember the injector has 12 volts with ignition on, but the ground goes via the ecm (does the ecm have a good ground connection). I pinned out the ECM and the ground was good.
s it the correct ecm did you pull the chips from your old ecm and put them in the new ecm??? I bought the 1985 ECM
Reco ecm,s come without the chip. The chip was made for me by Oscar Sebastian for the 1985 4 plus 3. But I am actually thinking of eBay for a used i.e. proven PROM.
The injectors batch fire all left then all right via ecm pulse width. this I found out from Gordon Kilebrew
I want to thank you for the wiring information. I will be looking at that.
Thank you for your time
see link below Post 5 has a injector wiring diagram
s it the correct ecm did you pull the chips from your old ecm and put them in the new ecm??? I bought the 1985 ECM
Reco ecm,s come without the chip. The chip was made for me by Oscar Sebastian for the 1985 4 plus 3. But I am actually thinking of eBay for a used i.e. proven PROM.
The injectors batch fire all left then all right via ecm pulse width. this I found out from Gordon Kilebrew
I want to thank you for the wiring information. I will be looking at that.
Thank you for your time
see link below Post 5 has a injector wiring diagram